Global Reporting Format (GRF) Course
Global Reporting Format (GRF) Course
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TABLE OF CONTENTS
Module
01
Chapter
Page No
Chapter-1
Definitions
Abbreviations and Acronyms
1-5
5-6
Chapter-2
Introduction
7-8
Chapter-3
Background
ICAO history
Work on GRF conducted by the ICAO Frictional Task Force (FTF).
 Major amendments - SARPs-Annex 14
 Major amendments - PANS-ATM
 Manual and Circulars developed
9-10
10
10
10-17
17-22
23
Chapter-4
Basic surface Friction Characteristics and the aircraft/runway
interaction.
Dynamic process-System response
02
24
25
Chapter-5
Runway surface conditions methodology - Fundamental elements,
conditions, descriptors
New Reporting Format - Runway condition code.
 (RWYCC).Assigning a runway condition code (RWYCC).
 Reporting of runway condition code from ATS to flight crew
for runway thirds.
Runway thirds-runway with displaced threshold
26-27
28
29
30
31
Chapter-6
Downgrade and upgrade criteria – procedures
32-35
Chapter-7
Runway condition assessment matrix (RCAM)
03
36-37
Chapter-8
Runway condition report – Basic information
38-40
Chapter-9
Runway Condition Report (RCR)
 Sections
 Examples
 flow charts
 Table-RCR information and source
 Worksheets
41-44
44
45-48
49
51-52
Chapter-10
Pavement
 functional requirements
 Surface conditions-precipitation-texture
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Module
Chapter
Page No
Chapter-11
Assessment methods and monitoring trends of change of surface
friction characteristics.
 Visual inspections and ruler measurements for humanmade assessment of runway surface contamination.
 Continuous friction measuring equipment receiving,
presenting and storing data.
 Assessment methods-Tables.
 Maintenance of “slippery wet” runway.
04
57
57
58-60
61-62
Chapter-12
Pilot report –AIREP feedback
Correlation of pilot reports of runway braking action with RWYCCs
64
65
Chapter-13
Aircraft runway performance implications
Landing and takeoff considerations
66
67-69
Chapter-14
Dissemination of information
 Aviation stakeholder’s activities and communication chain
for the dissemination of information.
 SNOWTAM Template
 SNOWTAM Format
 Instructions for the completion of the SNOWTAM format
 AIP,AIC,NOTAM,AIREP,ATC,ATC ,ATIS
 Communication network
 Digital NOTAM
Attachment ATT-1
Bibliography
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80-81
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MODULE-01
CHAPTER-1
1. Definitions, Abbreviations and Acronyms
1.1 Definitions
Aeronautical information circular (AIC). A notice containing information that does not
qualify for the origination of a NOTAM or for inclusion in the AIP, but which relates to flight
safety, air navigation, technical, administrative or legislative matters.
Aeronautical information management (AIM).The dynamic, integrated management of
aeronautical information through the provision and exchange of quality-assured digital
aeronautical data in collaboration with all parties.
Aeronautical information service (AIS). A service established within the defined area of
coverage responsible for the provision of aeronautical data and aeronautical information
necessary for the safety, regularity and efficiency of air navigation.
Air-report. A report from an aircraft in flight prepared in conformity with requirements for
position, and operational and/or meteorological reporting.
Air traffic service. A generic term meaning variously, flight information service, alerting
service, air traffic advisory service, air traffic control service (area control service, approach
control service or aerodrome control service).
Automatic terminal information service (ATIS). The automatic provision of current, routine
information to arriving and departing aircraft throughout 24 hours or a specified portion
thereof:
Data link-automatic terminal information service (D-ATIS). The provision of ATIS via data
link.
Voice-automatic terminal information service (Voice-ATIS). The provision of ATIS by
means of continuous and repetitive voice broadcasts.
Braking action. A term used by pilots to characterize the deceleration associated with the
wheel braking effort and directional controllability of the aircraft.
Coefficient of friction. A dimensionless ratio of the friction force between two bodies to the
normal force pressing these two bodies together.
Contaminant. A deposit (such as snow, slush, ice, standing water, mud, dust, sand, oil and
rubber) on an aerodrome pavement, the effect of which is detrimental to the friction
characteristics of the pavement surface.
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Critical tire-to-ground contact area. An area (approximately 4 square meters for the largest
aircraft currently in service) which is subject to forces that drive the rolling and braking
characteristics of the aircraft, as well as directional control.
ESDU scale. A grouping of hard runway surfaces based on macrotexture depth.
Friction. A resistive force along the line of relative motion between two surfaces in contact.
Friction characteristics. The physical, functional and operational features or attributes of
friction arising from a dynamic system.
Grooved or porous friction course runway. A paved runway that has been constructed
and maintained with lateral grooving or a porous friction course (PFC) surface to improve
braking characteristics when wet.
Hazard. A condition or an object with the potential to cause injuries to personnel, damage to
equipment or structures, loss of material, or reduction of the ability to perform a prescribed
function.
Landing distance available (LDA). The length of runway which is declared available and
suitable for the ground run of an aeroplane landing.
NOTAM. A notice distributed by means of telecommunication containing information
concerning the establishment, condition or change in any aeronautical facility, service,
procedure or hazard, the timely knowledge of which is essential to personnel concerned with
flight operations.
Operational personnel. Personnel involved in aviation activities who are in a position to
report safety information.
Note.— Such personnel include, but are not limited to: flight crews; air traffic
controllers; aeronautical station operators; maintenance technicians; personnel of
aircraft design and manufacturing organizations; cabin crews; flight dispatchers;
apron personnel and ground handling personnel.
Retardation. The deceleration of a vehicle braking, measured in m/s
Runway. A defined rectangular area on a land aerodrome prepared for the landing and takeoff of aircraft.
Runway condition assessment matrix (RCAM). A matrix allowing the assessment of the
runway condition code, using associated procedures, from a set of observed runway surface
condition(s) and pilot report of braking action.
Runway condition code (RWYCC). A number describing the runway surface condition to
be used in the runway condition report.
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Note. — The purpose of the runway condition code is to permit an operational
aeroplane performance calculation by the flight crew.
Runway condition report (RCR). A comprehensive standardized report relating to runway
surface conditions and its effect on the aeroplane landing and take-off performance.
Runway Safety Team. A team comprising representatives from the [aerodrome operator], air
traffic service provider, airlines or aircraft operators, pilot and air traffic controllers
associations and any other group with a direct involvement in runway operations [at a specific
aerodrome,] that advise the appropriate management on potential runway [safety] issues and
recommend mitigation strategies.
Runway surface condition(s). A description of the condition(s) of the runway surface used
in the runway condition report which establishes the basis for the determination of the runway
condition code for aeroplane performance purposes.
Note 1. — The runway surface conditions used in the runway condition report
establish the performance requirements between the aerodrome operator,
aeroplane manufacturer and aeroplane operator.
Note 2. — Aircraft de-icing chemicals and other contaminants are also
reported but are not included in the list of runway surface condition descriptors
because their effect on runway surface friction characteristics and the runway
condition code cannot be evaluated in a standardized manner.
a) Dry runway. A runway is considered dry if its surface is free of visible moisture
and not contaminated within the area intended to be used.
b) Wet runway. The runway surface is covered by any visible dampness or water
upto and including 3 mm deep within the intended area of use.
c) Slippery wet runway. A wet runway where the surface friction characteristics of a
significant portion of the runway have been determined to be degraded.
d) Contaminated runway. A runway is contaminated when a significant portion of
the runway surface area (whether in isolated areas or not) within the length and
width being used is covered by one or more of the substances listed in the runway
surface condition descriptors.
e) Runway surface condition descriptors. One of the following elements on the
surface of the runway:
Note. — The descriptions for e) i) to e) viii) are used solely in the
context of the runway condition report and are not intended to
supersede or replace any existing WMO definitions.
i)
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Compacted snow. Snow that has been compacted into a solid mass
such that aeroplane tires, at operating pressures and loadings, will run
on the surface without significant further compaction or rutting of the
surface.
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ii)
Dry snow. Snow from which a snowball cannot readily be made.
iii)
Frost. Frost consists of ice crystals formed from airborne moisture on a
surface whose temperature is below freezing. Frost differs from ice in
that the frost crystals grow independently and therefore have a more
granular texture.
Note 1. — Below freezing refers to air temperature equal to or
less than the freezing point of water (0 degree Celsius).
Note 2. — Under certain conditions frost can cause the surface
to become very slippery and it is then reported appropriately as
reduced braking action.
iv)
Ice. Water that has frozen or compacted snow that has transitioned
into ice, in cold and dry conditions.
v)
Slush. Snow that is so water-saturated that water will drain from it when
a handful is picked up or will splatter if stepped on forcefully.
vi)
Standing water. Water of depth greater than 3 mm.
Note. — Running water of depth greater than 3 mm is reported as
standing water by convention.
vii)
Wet ice. Ice with water on top of it or ice that is melting.
Note. — Freezing precipitation can lead to runway conditions
associated with wet ice from an aeroplane performance point of view.
Wet ice can cause the surface to become very slippery. It is then
reported appropriately as reduced braking action in line with
procedures in the PANS-Aerodromes (Doc 9981).
viii)
Wet snow. Snow that contains enough water content to be able to
make a well-compacted, solid snowball, but water will not squeeze
out.
Safety. The state in which risks associated with aviation activities, related to, or in direct
support of the operation of aircraft, are reduced and controlled to an acceptable level.
Safety management system (SMS). A systematic approach to managing safety, including
the necessary organizational structures, accountability, responsibilities, policies and
procedures.
Significant change. A change in the magnitude of a hazard, which leads to a change in the
safe operation of the aircraft.
Skid resistant. A runway surface that is designed, constructed and maintained to have good
water drainage, which minimizes the risk of hydroplaning when the runway is wet and
provides aircraft braking performance shown to be better than that used in the airworthiness
standards for a wet, smooth runway.
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SNOWTAM. A special series NOTAM given in a standard format providing a surface
condition report notifying the presence or cessation of hazardous conditions due to snow, ice,
slush, frost, standing water or water associated with snow, slush, ice or frost on the
movement area.
Surface friction characteristics. The physical, functional and operational features or
attributes of friction that relate to the surface properties of the pavement and can be
distinguished from each other.
Note. — The friction coefficient is not a property of the pavement surface but a
system response from the measuring system. Friction coefficient can be used to
evaluate the surface properties of the pavement provided that the properties
belonging to the measuring system are controlled and kept stable.
V1 (Speed).The maximum speed in the take-off at which the pilot must take the first action
(e.g. apply brakes, reduce thrust, deploy speed brakes) to stop the aeroplane within the
accelerate-stop distance.V1 also means the minimum speed in the take-off, following a
failure of the critical engine at the calibrated airspeed at which the critical engine is assumed
to fail (Vef), at which the pilot can continue the take-off and achieve the required height
above the take-off surface within the take-off distance.
1.2 Abbreviations and Acronyms
AC Advisory circular (FAA)
AFM Aircraft flight manual
AIC Aeronautical information circular
AIM Aeronautical information management
AIP Aeronautical information publication
AIREP Air-report
AIS Aeronautical information services
ARC Aviation Rulemaking Committee (FAA)
ASTM American Society for Testing and Materials
ATC Air traffic control (in general)
ATIS Automatic terminal information service
ATM Air traffic management
ATS Air traffic service
CFR Code of Federal Regulations (FAA)
CRM Crew resource management
CS Certification specifications (EASA)
EASA European Aviation Safety Agency
ESDU Engineering Sciences Data Unit
FAA Federal Aviation Administration (United States)
FAR Federal Aviation Regulations (United States)
FTF Friction Task Force
HF High frequency
HMA Hot-mix asphalt
IATA International Air Transport Association
ICAO International Civil Aviation Organization
JAA Joint Aviation Authorities (Europe)
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JAR Joint Aviation Requirements (Europe)
LDA Landing distance available
MET Meteorological services
MPD Mean profile depth
MTD Mean texture depth
NASA National Aeronautics and Space Administration (United States)
NOTAM Notice to airmen
OAT Outside air temperature
PANS Procedures for Air Navigation Services
PCC Portland cement concrete
PFC Porous friction course
PSV Polished stone value
RCAM Runway condition assessment matrix
RCR Runway condition report
RESA Runway end safety area
RST Runway Safety Team
RWYCC Runway condition code SARPS Standards and Recommended Practices
SLA Service level agreement
SMS Safety management system
SOP Standard operating procedure
TWY Taxiway
µ Mu (coefficient of friction)
µmax Maximum friction coefficient as experienced by an aircraft
VHF Very high frequency
WMO World Meteorological Organization
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CHAPTER-2
2. Introduction
2.1 Runway accidents and incidents are aviation’s number one safety-related risk category. A
primary factor contributing to this risk includes runway excursions during take-off or landing in
adverse weather conditions; the runway surface may be contaminated by snow, ice,
slush or water, with a potentially negative impact on an aircraft’s braking, acceleration
or controllability. A statistical analysis of high-risk accidents from 2008 to 2016 has shown
that runway safety-related accidents, notably runway excursions, remain the top contributing
factors included poor braking action due to contaminated runways or taxiways combined
with shortfalls in the accuracy and timeliness of runway surface conditions assessment
and reporting. See figure – 2.1 below.
Figure-2.1
2.2 Two runway excursions which are notable because they resulted in fatalities, destruction
of the aircraft, or substantial aviation safety changes or improvements are given below,
while a brief on 17 such runway excursions since year 1993 is placed at attachment
ATT-1.
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Southwest Airlines Flight 1248 Year
2005 Midway International Airport,
Chicago, Illinois, U.S.A
Boeing 737-700 overran the runway
while landing in a snowstorm and
crashed into automobile traffic, killing
one person on the ground.
Air India Express Flight 1344 Year
2020 Calicut International Airport,
Kerala, India
A Boeing 737-800 overran the tabletop
runway, skidding off the end of the
runway and crashing into a gorge. The
aircraft was carrying 190 people
including 6 crew members. A total of
20 people, including both pilots, were
killed in the crash.
2.3
In 2017, ICAO’s Global Runway Safety Action Plan called for the widespread deployment of
the ICAO format for assessing and reporting runway surface conditions as an effective
mitigation. This new methodology, commonly known as the Global Reporting Format (GRF)
will be applicable from 4 November 2021. It has its origins in the FAA’s Take-off and
Landing Performance Assessment (TALPA). The GRF targets the standardized reporting
of runway surface conditions on wet and contaminated runways, the impact of which is then
directly correlated with an aircraft’s performance, enabling a better flight crew prediction of
their take-off and landing performance as well as an improved situation awareness.
2.4 The ICAO GRF methodology will improve the flight crew’s assessment of the take-off and
landing performance of aeroplanes. It is intended to cover conditions found in all climates and
provides a means for aerodrome operators to rapidly and correctly assess the conditions,
whether a wet runway, snow, slush, ice or frost, including rapidly changing conditions such as
those experienced during winter or in tropical climates. The information can be provided to
the flight crew via various channels, such as the revised SNOWTAM or by air traffic control.
This is a conceptual change for the airport as it no longer just reports a series of
observations and measurements, but it also turns this information into an overall
assessment of the effect that the surface condition has on the aeroplane performance.
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CHAPTER-3
3. Background, ICAO history and work on GRF conducted by the ICAO Frictional Task
Force (FTF).
3.1
Following the runway overrun accident of a Boeing 737 at Chicago Midway airport in
December of 2005, the Federal Aviation Administration (FAA) and industry developed a
new methodology for conveying actual runway conditions. It communicates actual runway
conditions to pilots in terms that directly relate to expected aircraft performance. This
methodology was based on recommendations in year 2009 from the Takeoff and Landing
Performance Assessment (TALPA) Aviation Rule making Committee (ARC). At the core of this
recommendation is the concept of using the included Runway Condition Assessment Matrix
(RCAM) as the basis for performing runway condition assessments by airport operators and for
interpreting the reported runway conditions by pilots in a standardized format based on
airplane performance data supplied by airplane manufacturers for each of the stated
contaminant types and depths. The concept attempts, to the maximum extent feasible, to
replace subjective judgments of runway conditions with objective assessments which
are tied directly to contaminant type and depth categories, which have been determined
by airplane manufacturers to cause specific changes in the airplane braking
performance.
3.2 ICAO – HISTORY
3.2.1
To disseminate information on runway surface conditions, the ICAO SNOWTAM format was
developed and introduced in 1967 arising from a detailed proposal from the International Air
Transport Association (IATA) in 1963. The SNOWTAM format has not gained global
acceptance and has been implemented differently among States, resulting in
inconsistent information being provided to aircraft operators and pilots. It was also
recognized that Runway condition reports should be timely, accurate and consistent with
the need to conduct aircraft operations.
3.3 ICAO Friction Task Force (FTF)
3.3.1
In view of the historical developments mentioned in the aforesaid para, it was considered
timely for ICAO to develop international specifications on, inter alia, the functions, principles
and basic technical and operational characteristics of friction measuring devices. In 2006
the Aerodromes Operations and Services Working Group, under the aegis of the
Aerodromes Panel, established the ICAO Friction Task Force (FTF) with the following
deliverables:
a) Propose appropriate amendments to the relevant Standards and Recommended
Practices (SARPs) in ICAO Annexes, primarily Annex 14, Volume I, supported by
updated guidance material;
b) Develop an ICAO circular on assessing, measuring and reporting runway surface
conditions including state-of-the-art treatment of friction issues; and
c) Propose an action plan for tasks that require future work.
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3.3.2
The ICAO Friction task force (FTF) formally commenced its work in 2008.The Friction task
force (FTF) was asked to:
a) address the problem statement ‒ runway surface conditions have contributed to many
safety events and investigations have revealed shortfalls in the accuracy and
timeliness of assessment and reporting methods currently provided for in ICAO
provisions and guidance material;
b) develop provisions on the reporting of runway surface conditions in Annex 14, Volume I,
and other related Annexes and Procedures for Air Navigation Services (PANS);
c) develop guidance on operational requirements for aeroplane performance; and
d) develop guidance for the assessment of runway surface conditions, including friction level
and where contamination exists.
3.3.3
Frictional task force (FTF) developed the Enhanced global reporting format for
assessing and reporting runway surface condition which was adopted by the ICAO
council effective 22 February 2016, applicable 05 November 2020. ICAO in 2020
deferred the applicable date to 04 November 2021 due to pandemic COVID-19. Brief
account of major work undertaken by the ICAO Functional Task Force (FTF) to amend the
ICAO SARPs, PANS and to develop other supporting ICAO guidance material including
ICAO circulars are presented as extracts of ICAO Annex-14 and PANS-ATM as follows.
(Extracts) - Annex- 14 - Standard and Recommended Practices (SARPs)
2.9 Condition of the movement area and related facilities
2.9.1 Information on the condition of the movement area
and the operational status of related facilities shall be
provided to the appropriate aeronautical information
services units, and similar information of operational
significance to the air traffic services units, to enable those
units to provide the necessary information to arriving and
departing aircraft. The information shall be kept up to date
and changes in conditions reported without delay.
Note. — The nature, format and conditions of the
information to be provided are specified in the PANS-AIM
(Doc 10066) and the PANS-ATM (Doc 4444).
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(Extracts) - Annex- 14 - Standard and Recommended Practices
(SARPs)
2.9.2 The condition of the movement area and the operational status of
related facilities shall be monitored, and reports on matters of
operational significance affecting aircraft and aerodrome operations
shall be provided in order to take appropriate action, particularly in
respect of the following:
a) construction or maintenance work;
b) rough or broken surfaces on a runway, a taxiway or an apron;
c) snow, slush, ice, or frost on a runway, a taxiway or an apron;
[applicable until 3 November 2021]
c) water, snow, slush, ice, or frost on a runway, a taxiway or an apron;
[applicable as of 4 November 2021]
d) water on a runway, a taxiway or an apron; [applicable until 3
November 2021]
e) anti-icing or de-icing liquid chemicals or other contaminants on a
runway, taxiway or apron;
f) snow banks or drifts adjacent to a runway, a taxiway or an apron;
g) other temporary hazards, including parked aircraft;
h) failure or irregular operation of part or all of the aerodrome visual
aids; and
i) failure of the normal or secondary power supply.
Note 1.—Until 3 November 2021, other contaminants may
include mud, dust, sand, volcanic ash, oil and rubber. Annex 6,
Part I — International Commercial Air Transport — Aeroplanes,
Attachment C provides guidance on the description of runway
surface conditions. Additional guidance is included in the
Airport Services Manual (Doc 9137), Part 2.
Note 2. — Until 3 November 2021, particular attention would
have to be given to the simultaneous presence of sno
w,
slush, ice, wet ice, snow on ice with anti-icing or de-icing liquid
chemicals.
Note 3. — Until 3 November 2021, see 2.9.11 for a list of
winter contaminants to be reported.
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Note 1.—As of 4 November 2021, other contaminants may
include mud, dust, sand, volcanic ash, oil and rubber.
Procedures for monitoring and reporting the conditions of the
movement area are included in the PANS-Aerodromes (Doc
9981).
Note 2.—As of 4 November 2021, the Aeroplane Performance
Manual (Doc 10064) provides guidance on aircraft performance
calculation requirements regarding the description of runway
surface conditions in 2.9.2 c), e) and f).
Note 3.—As of 4 November 2021, origin and evolution of data,
assessment process and the procedures are prescribed in the
PANS-Aerodromes (Doc 9981). These procedures are intended
to fulfil the requirements to achieve the desired level of safety
for aeroplane operations prescribed by Annex 6 and Annex 8
and to provide the information fulfilling the syntax requirements
for dissemination specified in Annex 15 and the PANS-ATM
(Doc 4444).
(Extracts) - Annex- 14 -Standard and Recommended Practices (SARPs)
2.9.3 Until 3 November 2021, to facilitate compliance with 2.9.1 and
2.9.2, inspections of the movement area shall be carried out each day
at least once where the code number is 1 or 2 and at least twice where
the code number is 3 or 4.
Note.— Guidance on carrying out daily inspections of the movement
area is given in the Airport Services Manual (Doc 9137), Part 8 and in
the Manual of Surface Movement Guidance and Control Systems
(SMGCS) (Doc 9476).
2.9.3 As of 4 November 2021, to facilitate compliance with 2.9.1 and
2.9.2, the following inspections shall be carried out each day:
a) for the movement area, at least once where the aerodrome
reference code number is 1 or 2 and at least twice where the
aerodrome reference code number is 3 or 4; and
b) for the runway(s), inspections in addition to a) whenever the runway
surface conditions may have changed significantly due to
meteorological conditions.
2.9.4 Recommendation.—Until 3 November 2021, personnel
assessing and reporting runway surface conditions required in 2.9.2
and 2.9.8 should be trained and competent to meet criteria set by the
State.
Note.— Guidance on criteria is included in the Airport Services
Manual (Doc 9137), Part 8, Chapter 7.
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2.9.4 As of 4 November 2021, personnel assessing and
reporting runway surface conditions required in 2.9.2 and 2.9.5
shall be trained and competent to perform their duties.
Note 1.— Guidance on training of personnel is given in
Attachment A, Section 6 [applicable 4 November
2021].
Note 2.— Information on training for personnel
assessing and reporting runway surface conditions is
available in the PANS-Aerodromes (Doc 9981).
Water on a runway [applicable until 3 November 2021]
2.9.5 Recommendation.— Whenever water is present on a runway, a
description of the runway surface conditions should be made available
using the following terms:
DAMP — the surface shows a change of colour due to moisture.
WET — the surface is soaked but there is no standing water.
STANDING WATER — for aeroplane performance purposes, a
runway where more than 25 per cent of the runway surface area
(whether in isolated areas or not) within the required length and width
being used is covered by water more than 3 mm deep.
2.9.6 Information that a runway or portion thereof may be slippery
when wet shall be made available.
Note.— The determination that a runway or portion thereof may
be slippery when wet is not based solely on the friction
measurement obtained using a continuous friction measuring
device. Supplementary tools to undertake this assessment are
described in the Airport Services Manual (Doc 9137), Part 2.
(Extracts) - Annex- 14 -Standard and Recommended Practices (SARPs)
2.9.7 Notification shall be given to aerodrome users when the
friction level of a paved runway or portion thereof is less than
that specified by the State in accordance with 10.2.3.
SLUSH;
ICE;
WET ICE;
FROST;
DRY SNOW ON ICE;
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WET SNOW ON ICE;
CHEMICALLY TREATED;
SANDED
and should include, where applicable, the assessment of
contaminant depth.
2.9.12 Recommendation.— Whenever dry snow, wet snow or
slush is present on a runway, an assessment of the mean
depth over each third of the runway should be made to an
accuracy of approximately 2 cm for dry snow, 1 cm for wet
snow and 0.3 cm for slush.
Runway surface condition(s) for use in the runway condition report
[applicable as of 4 November 2021]
Introductory Note.— The philosophy of the runway condition
report is that the aerodrome operator assesses the runway
surface conditions whenever water, snow, slush, ice or frost are
present on an operational runway. From this assessment, a
runway condition code (RWYCC) and a description of the
runway surface are reported which can be used by the flight
crew for aeroplane performance calculations. This report,
based on the type, depth and coverage of contaminants, is the
best assessment of the runway surface condition by the
aerodrome operator; however, all other pertinent information
may be taken into consideration. See Attachment A, Section 6,
for further details. The PANS-Aerodromes (Doc 9981) contains
procedures on the use of the runway condition report and
assignment of the RWYCC in accordance with the runway
condition assessment matrix (RCAM).
(Extracts) - Annex- 14 -Standard and Recommended Practices (SARPs)
2.9.5 The runway surface condition shall be assessed and reported
through a runway condition code (RWYCC) and a description using the
following terms:
COMPACTED SNOW
DRY
DRY SNOW
DRY SNOW ON TOP OF COMPACTED SNOW
DRY SNOW ON TOP OF ICE
FROST
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ICE
SLUSH
STANDING WATER
WATER ON TOP OF COMPACTED SNOW
WET
WET ICE
WET SNOW
WET SNOW ON TOP OF COMPACTED SNOW
WET SNOW ON TOP OF ICE
CHEMICALLY TREATED
LOOSE SAND
Note 1.— The runway surface conditions are those conditions for
which, by means of the methods described in the PANS-Aerodromes
(Doc 9981), the flight crew can derive appropriate aeroplane
performance.
Note 2.— The conditions, either singly or in combination with other
observations, are criteria for which the effect on aeroplane
performance is sufficiently deterministic to allow assignment of a
specific runway condition code.
Note 3.— The terms CHEMICALLY TREATED and LOOSE SAND do
not appear in the aeroplane performance section but are used in the
situational awareness section of the runway condition report.
2.9.6 Whenever an operational runway is contaminated, an assessment of the
contaminant depth and coverage over each third of the runway shall be made
and reported.
Note.— Procedures on depth and coverage reporting are found in the
PANS-Aerodromes (Doc 9981).
(Extracts) - Annex- 14 -Standard and Recommended Practices (SARPs)
2.9.7 When friction measurements are used as part of the overall runway
surface assessment on compacted snow- or ice-covered surfaces, the friction
measuring device shall meet the standard set or agreed by the State.
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2.9.8 Recommendation.— Friction measurements made on runway surface
conditions with contaminants other than compacted snow and ice should not
be reported.
Note.— Friction measurements on loose contaminants such as snow
and slush, in particular, are unreliable due to drag effects on the
measurement wheel.
2.9.9 Information that a runway or portion thereof is slippery wet shall be made
available.
Note 1.— The surface friction characteristics of a runway or a
portion thereof can be degraded due to rubber deposits,
surface polishing, poor drainage or other factors. The
determination that a runway or portion thereof is slippery wet
stems from various methods used solely or in combination.
These methods may be functional friction measurements, using
a continuous friction measuring device, that fall below a
minimum standard as defined by the State, observations by
aerodrome maintenance personnel, repeated reports by pilots
and aircraft operators based on flight crew experience, or
through analysis of aeroplane stopping performance that
indicates a substandard surface. Supplementary tools to
undertake this assessment are described in the PANSAerodromes (Doc 9981).
(Extracts) - Annex- 14 -Standard and Recommended Practices (SARPs)
10.2.3 A paved runway shall be maintained in a condition so as to provide
surface friction characteristics at or above the minimum friction level specified
by the State.
Note.— Until 3 November 2021, the Airport Services Manual (Doc
9137), Part 2, contains further information on this subject.
Note.—As of 4 November 2021, Assessment, Measurement and
Reporting of Runway Surface Conditions (Cir 355) contains further
information on this subject.
10.2.4 Runway surface friction characteristics for maintenance purposes shall
be periodically measured with a continuous friction measuring device using
self-wetting features and documented. The frequency of these measurements
shall be sufficient to determine the trend of the surface friction characteristics
of the runway.
Note 1. — Until 3 November 2021, guidance on evaluating the friction
characteristics of a runway is provided in Attachment A, Section 7.
Additional guidance is included in the Airport Services Manual (Doc
9137), Part 2.
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Note 1.—As of 4 November 2021, guidance on evaluating the runway
surface friction characteristics is provided in Assessment,
Measurement and Reporting of Runway Surface Conditions (Cir 355).
Note 2. —Until 3 November 2021, the objective of 10.2.3, 10.2.4,
10.2.7 and 10.2.8 is to ensure that the surface friction characteristics
for the entire runway remain at or above a minimum friction level
specified by the State.
Note 2.—As of 4 November 2021, the objective of 10.2.3 to 10.2.7
and 10.2.9 is to ensure that the surface friction characteristics for the
entire runway remain at or above a minimum friction level specified by
the State.
Note 3.—Until 3 November 2021, guidance for the determination of
the required frequency is provided in Attachment A, Section 7 and in
the Airport Services Manual (Doc 9137), Part 2, Appendix 5.
10.2.5 As of 4 November 2021, when runway surface friction measurements
are made for maintenance purposes using a self-wetting continuous friction
measuring device, the performance of the device shall meet the standard set
or agreed by the State.
10.2.6 As of 4 November 2021, personnel measuring runway surface friction
required in 10.2.5 shall be trained to fulfil their duties.
(Extracts) – PANS-ATM
CHAPTER 4 GENERAL PROVISIONS FOR AIR TRAFFIC SERVICES
4.12
REPORTING
OF
OPERATIONAL
METEOROLOGICAL INFORMATION
AND
4.12.7 Forwarding of braking action information
When receiving special air-reports by voice communications
concerning braking action encountered that is not as good as
that reported, air traffic service units shall forward them without
delay to the appropriate aerodrome operator.
(Extracts) – PANS-ATM
7.5.2 Essential information on aerodrome conditions shall include information
relating to the following:
a) construction or maintenance work on, or immediately adjacent to the
movement area;
b) rough or broken surfaces on a runway, a taxiway or an apron, whether
marked or not;
c) water, snow, slush, ice or frost on a runway, a taxiway or an apron;
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d) anti-icing or de-icing liquid chemicals or other contaminant on a runway,
taxiway or apron;
e) snow banks or drifts adjacent to a runway, a taxiway or an apron;
f) other temporary hazards, including parked aircraft and birds on the ground or
in the air;
g) failure or irregular operation of part or all of the aerodrome lighting system;
h) any other pertinent information.
(Extracts) - PANS-ATM
11.4.3.4
MESSAGES CONTAINING INFORMATION ON AERODROME CONDITIONS
11.4.3.4.1 Whenever information is provided on aerodrome conditions, this shall
be done in a clear and concise manner so as to facilitate appreciation by the pilot
of the situation described. It shall be issued whenever deemed necessary by the
controller on duty in the interest of safety, or when requested by an aircraft. If the
information is provided on the initiative of the controller, it shall be transmitted to
each aircraft concerned in sufficient time to enable the pilot to make proper use of
the information.
11.4.3.4.2
Whenever information is provided concerning runway surface
conditions that may adversely affect aircraft braking action, the following terms
shall be used, as necessary:
COMPACTED SNOW
DRY
DRY SNOW
DRY SNOW ON TOP OF COMPACTED SNOW
DRY SNOW ON TOP OF ICE
FROST
ICE
SLUSH
STANDING WATER
WATER ON TOP OF COMPACTED SNOW
WET
WET ICE
WET SNOW
WET SNOW ON TOP OF COMPACTED SNOW
WET SNOW ON TOP OF ICE
11.4.3.4.3 Appropriate ATS units shall have available for transmission
to aircraft, upon request, the Runway Condition Report information.
This shall be passed to aircraft in the order of the direction of landing
or take-off.
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Chapter 12 Phraseologies
a) [(location)] RUNWAY (number) SURFACE
CONDITION
[CODE (three digit number)] followed as necessary by:
1) ISSUED AT (date and time UTC);
(Extracts) - PANS – ATM
2) DRY, or WET ICE, or WATER ON TOP OF COMPACTED
SNOW, or DRY SNOW, or DRY SNOW ON TOP OF ICE, or WET
SNOW ON TOP OF ICE, or ICE, or SLUSH, or STANDING
WATER, or COMPACTED SNOW, or WET SNOW, or DRY SNOW
ON TOP OF COMPACTED SNOW, or WET SNOW ON TOP OF
COMPACTED SNOW, or WET, or FROST;
3) DEPTH ((depth of deposit) MILLIMETRES or NOT REPORTED;
4) COVERAGE (number) PER CENT or NOT REPORTED);
5) ESTIMATED SURFACE FRICTION (GOOD, or GOOD TO
MEDIUM, or MEDIUM, or MEDIUM TO POOR, or POOR, or LESS
THAN POOR);
6) AVAILABLE WIDTH (number) METRES;
7) LENGTH REDUCED TO (number) METRES;
8)
DRIFTING SNOW;
9)
LOOSE SAND;
10)
CHEMICALLY TREATED;
11) SNOWBANK (number) METRES [LEFT, or RIGHT,
or LEFT AND RIGHT] [OF or FROM] CENTRELINE;
(Extracts) - PANS-ATM
Phraseologies PANS –ATM DOC 4444
12) TAXIWAY (identification of taxiway) SNOWBANK
(number) METRES [LEFT, or RIGHT, or LEFT AND
RIGHT] [OF or FROM] CENTRELINE;
13) ADJACENT SNOWBANKS;
14) TAXIWAY (identification of taxiway) POOR;
15) APRON (identification of apron) POOR;
16) Plain language remark
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b) [(location)] RUNWAY SURFACE CONDITION RUNWAY (number) NOT CURRENT;
c) LANDING SURFACE (condition);
d) CAUTION CONSTRUCTION WORK (location);
e) CAUTION (specify reasons) RIGHT (or LEFT), (or BOTH SIDES) OF RUNWAY [(number)];
f) CAUTION WORK IN PROGRESS (or OBSTRUCTION) (position and any necessary advice);
g) BRAKING ACTION REPORTED BY (aircraft type) AT (time) GOOD (or GOOD TO MEDIUM, or MEDIUM,
or MEDIUM TO POOR, or POOR);
h) TAXIWAY (identification of taxiway) WET [or STANDING WATER, or SNOW REMOVED (length and
width as applicable), or CHEMICALLY TREATED, or COVERED WITH PATCHES OF DRY SNOW (or
WET SNOW, or COMPACTED SNOW, or SLUSH, or FROZEN SLUSH, or ICE, or WET ICE, or ICE
UNDERNEATH, or ICE AND SNOW, or SNOWDRIFTS, or FROZEN RUTS AND RIDGES or LOOSE
SAND)];
i) TOWER OBSERVES (weather information);
j) PILOT REPORTS (weather information).
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Appendix 1
INSTRUCTIONS FOR AIR-REPORTING BY VOICE COMMUNICATIONS
1. Reporting instructions
MODEL AIREP SPECIAL
SECTION
ITEM
3
9
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PARAMETER
(Extracts) - PANS-ATM
Phenomenon encountered or
observed, prompting a special
air-report:
•
Moderate turbulence
•
Severe turbulence
•
Moderate icing
•
Severe icing
•
Severe
mountain
wave
•
Thunderstorms without
hail
•
Thunderstorms with hail
•
Heavy dust/sandstorm
•
Volcanic ash cloud
•
Pre-eruption
volcanic
activity or volcanic eruption
Runway braking action
•
Good
•
Good to Medium
•
Medium
•
Medium to Poor
•
Poor
•
Less than Poor
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TRANSMIT IN TELEPHONY as
appropriate
TURBULENCE MODERATE
TURBULENCE SEVERE
ICING MODERATE
ICING SEVERE
MOUNTAINWAVE SEVERE
THUNDERSTORMS
THUNDERSTORMS WITH HAIL
DUSTSTORM or SANDSTORM HEAVY
VOLCANIC ASH CLOUD
PRE-ERUPTION VOLCANIC ACTIVITY
or VOLCANIC ERUPTION
GOOD
GOOD TO MEDIUM
MEDIUM
MEDIUM TO POOR
POOR
LESS THAN POOR
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Section 3
Item 9 — PHENOMENON PROMPTING A SPECIAL AIR-REPORT. Report one of the following
phenomena encountered or observed:


Good braking action as “BRAKING ACTION GOOD”
Good to medium braking action as “BRAKING ACTION GOOD TO MEDIUM”
Appendix 1




A1-5
Medium braking action as “BRAKING ACTION MEDIUM”
Medium to poor braking action as “BRAKING ACTION MEDIUM TO POOR”
Poor braking action as “BRAKING ACTION POOR”
Less than poor braking action as “BRAKING ACTION LESS THAN POOR”
The following specifications apply:
Good — Braking deceleration is normal for the wheel braking effort applied and directional control is
normal.
Good to medium — Braking deceleration or directional control is between Good and Medium.
Medium — Braking deceleration is noticeably reduced for the wheel braking effort applied or
directional control is noticeably reduced.
Medium to poor — Braking deceleration or directional control is between Medium and Poor.
Poor — Braking deceleration is significantly reduced for the wheel braking effort applied or directional
control is significantly reduced.
Less than poor — Braking deceleration is minimal to non-existent for the wheel braking effort applied
or directional control is uncertain.
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Work performed by ICAO Frictional Task Force (FTF) on ICAO Annexes,
manuals and circulars to amend or develop are shown below.
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CHAPTER - 4
4. Basic surface Friction Characteristics and the aircraft/runway interaction.
4.1 Friction issues relate to aircraft/runway interaction that depends on the critical tire-to-ground
contact area. The basic friction characteristics of the critical tire-to-ground contact area, the
latter being a part of a dynamic system, influences the available friction that can be utilized by
an aircraft. The basic friction characteristics are properties belonging to the individual
components of the system, such as:
a) pavement surface (runway);
b) tires (aircraft);
c) contaminants (between the tire and the pavement); and
d) atmosphere (temperature, radiation affecting the state of the contaminant).
The three main components of the system are (figure-4.1):
a) surface friction characteristics (static material properties);
b) dynamic system (aircraft and pavement in relative motion); and
c) system response (aircraft performance).
Figure 4.1
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4.2 The aircraft response depends largely on the available tire-pavement friction and the aircraft
anti-skid system. Figure-4.2 given below illustrates the friction characteristics and how they
interrelate in the dynamic system of an aircraft in motion.
Basic friction characteristics, the dynamic system and system response
Figure 4.2
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MODULE-02
CHAPTER-5
5. Runway surface conditions methodology - Fundamental elements, conditions,
descriptors and new Reporting Format - Runway condition code (RWYCC)
5.1 Runway surface conditions methodology - Fundamental elements, conditions and
descriptors. The definitions of the terms listed below define the fundamental, conceptual
part of the report and assessment of the runway surface conditions methodology.
5.1.1 There are five fundamental elements:
a) runway condition report (RCR);
b) runway condition assessment matrix (RCAM);
c) runway condition code (RWYCC);
d) runway surface conditions; and
e) runway surface condition descriptors.
5.1.2 There are four runway surface conditions:
a) dry runway;
b) wet runway;
c) slippery wet; and
d) contaminated runway.
5.1.3 There are eight contaminated runway surface condition descriptors:
a) compacted snow;
b) dry snow;
c) frost;
d) ice;
e) slush;
f) standing water;
g) wet ice; and
h) wet snow.
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Images - Runway surface condition descriptors
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5.1.4 Based on the defined concept outlined above, the RCR is a validated method that
replaces subjective judgements with objective assessments that are directly tied to
criteria relevant for aeroplane performance. These criteria have been determined by
aeroplane manufacturers to cause specific changes in aeroplane braking performance. It
constitutes the conceptual integrity of the global reporting format. Any change to the
definitions of the above elements can cause the conceptual integrity to fall apart.
5.2. New Reporting Format - Runway condition code (RWYCC)
5.2.1 The RWYCC reflects the runway braking capability as a function of the surface
conditions. With this information, the flight crew can derive, from the performance information
provided by the aeroplane manufacturer, the necessary stopping distance of an aircraft on
the approach under the prevailing conditions.
5.2.2 The reporting process begins with the evaluation of a runway by human observation,
normally performed by airport operations staff. A description of the surface contaminant
based on its type, depth and coverage for each third of the runway, is then used to
obtain a runway condition code (RWYCC) specific to the conditions observed. The
evaluation and associated RWYCC are used to complete a standard report called the runway
condition report (RCR) which is then forwarded to air traffic control (ATC) and the
aeronautical information services (AIS) for onward dissemination to pilots.
5.2.3 Pilots use the RCR provided to determine the expected performance of their aircraft
by correlating the RWYCC or the reported runway condition description with performance
data provided by the aircraft manufacturer. This helps pilots to correctly carry out their
landing and take-off performance calculations for wet or contaminated runways. Pilots also
report their own observations of runway conditions once a landing has been completed,
thereby confirming the RWYCC or providing an alert to changing condition. Pilots use the
RCR provided to determine the expected performance of their aircraft by correlating the
RWYCC or the reported runway condition description with performance data provided by the
aircraft manufacturer. This relatively simple and globally applicable reporting methodology is
an important means by which the risk of runway excursion can be mitigated and the safety of
runway operations improved.
5.2.4 RWYCC is a single-digit number describing the deceleration and lateral control
capability for the runway surface condition. They are assigned to each runway third whenever
the coverage of any water-based contaminant on any runway third exceeds 25 per cent. It is
the total assessment of the slipperiness of the surface, as judged by the trained and
competent aerodrome personnel, based on given procedures and all information available,
and enables flight crew to determine the effect of the runway surface condition on aeroplane
deceleration performance and control. There are seven surface condition levels
associated with RWYCC numbers zero to six, representing conditions that range from
too slippery to operate on (zero), to completely dry conditions (six), see Table 5.1
given below.
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Assigning a runway condition code (RWYCC).
Runway
condition description
Runway
condition
description
Runway
condition
code (RWYCC)
Runway
condition
code
RWYCC
DRY
6
FROST
WET (the runway surface is covered by any visible dampness
or water up to and including 3 mm deep)
5
SLUSH (up to and including 3 mm depth)
DRY SNOW (up to and including 3 mm depth)
WET SNOW (up to and including 3 mm depth)
COMPACTED SNOW
4
(Outside air temperature minus 15 degrees
Celsius and below)
WET (“Slippery wet” runway)
DRY SNOW (more than 3 mm depth)
WET SNOW (more than 3 mm depth)
DRY SNOW ON TOP OF COMPACTED SNOW (any depth)
WET SNOW ON TOP OF COMPACTED SNOW (any depth)
COMPACTED SNOW (outside air temperature above minus 15
degrees Celsius)
3
STANDING WATER (more than 3 mm depth)
SLUSH (more than 3 mm depth)
2
ICE
1
WET ICE
WATER ON TOP OF COMPACTED SNOW
0
DRY SNOW OR WET SNOW ON TOP OF ICE
Table 5.1
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5.2.5
Each RWYCC (except zero) is matched with a corresponding aeroplane deceleration
performance level. Airport operations staff assign the RWYCC based on the conditions
observed in their physical evaluations of runway conditions, which are then included in the
RCR. Measured coefficients of friction should no longer be communicated to pilots, but
restricted to use by the airport staff in consolidating the runway surface condition
assessment made from observed surface contamination characteristics like type, depth
and temperature. As a general rule, the runway contaminant type and depth permit
determination of a RWYCC, but a RWYCC can never give contaminant type and depth.
5.2.6
The reference runway length will typically be the full length of asphalt or concrete
available for take-off or landing. However, it should be noted that when a stopway exists at the
airport, it is excluded from the scope of the runway surface for which RWYCC are assigned.
This is shown in Figure-5.1 & 5.2 below, which illustrates the runway thirds and RWYCCs for
runways without, and then with, a displaced threshold. It is important for the flight crew to be
aware that the stopways will see less traffic than the rest of the runway surface and may
therefore be subject to more accumulation of contamination. If the condition of the stopway is
significantly different from the rest of the runway, this should be reported in the free text
comments of the RCR.
Figure 5.1 Reporting of runway condition code from ATS to flight crew for runway thirds
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Figure 5.2
Reporting of runway condition code for runway thirds from ATS to flight crew on
a runway with displaced threshold
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CHAPTER-6
6. Downgrade and upgrade criteria.
6.1.1 The variables, in table–5.1 given in chapter-5, which may affect the runway condition code are:
a) type of contaminant;
b) depth of contaminant; and
c) outside air temperature. Where available the runway surface temperature should
preferably be used.
Note.— At air temperatures of plus 3 degrees Celsius and below, with a dew
point spread of 3 degrees Celsius or less, the runway surface condition may
be more slippery than indicated by the runway condition code assigned by
Table. The narrow dew point spread indicates that the air mass is relatively
close to saturation which is often associated with actual precipitation,
intermittent precipitation, nearby precipitation or fog.
This may depend on its correlation with precipitation but it may also, at least in
part, depend on the exchange of water at the air-ice interface. Due to the other
variables involved, such as surface temperature, solar heating and ground
cooling or heating, a small temperature spread does not always mean that the
braking action will be more slippery. The observation should be used by
aerodrome operators as an indicator of slippery conditions but not as an
absolute.
6.1.2 The RWYCC shall be reported for each third of the runway assessed.
The assessment process shall include:
a) assessing and reporting the condition of the movement area;
b) providing the assessed information in the correct format; and
c) reporting significant changes without delay.
6.1.3 An assigned RWYCC 5, 4, 3 or 2 shall not be upgraded.
6.1.4 An assigned RWYCC 1 or 0 can be upgraded using the following procedures.
a) if a properly operated and calibrated State-approved measuring device and all other
observations support a higher RWYCC as judged by trained personnel;
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b) the decision to upgrade RWYCC 1 or 0 cannot be based upon one assessment
method alone. All available means of assessing runway slipperiness are to be used to
support the decision;
c) when RWYCC 1 or 0 is upgraded, the runway surface is assessed frequently during
the period the higher RWYCC is in effect to ensure that the runway surface condition
does not deteriorate below the assigned code; and
d) variables that may be considered in the assessment that may affect the runway
surface condition, include but are not limited to:
i) any precipitation conditions;
ii) changing temperatures;
iii) effects of wind;
iv) frequency of runway in use; and
v) type of aeroplane using the runway.
6.1.5 Upgrading of RWYCC 1 or 0 using the procedures in para 6.1.4, shall not be permitted to
go beyond a RWYCC 3.
6.1.6 If sand or other runway treatments are used to support upgrading, the runway surface is
assessed frequently to ensure the continued effectiveness of the treatment.
6.1.7 The RWYCC determined from Table-5.1 chapter 5 should be appropriately downgraded
considering all available means of assessing runway slipperiness, including the criteria given
below in Table 6.2.
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Pilot report
runwayofbraking
Pilot of
report
action
Runway braking
action
N/A
GOOD
GOOD TO MEDIUM
MEDIUM
MEDIUM TO POOR
POOR
LESS THAN POOR
Description
Runway condition code
Description
Runway condition
code (RWYCC)
RWYCC
6
Braking deceleration is normal
for the wheel braking effort
applied AND directional control
is normal
5
Braking deceleration OR
directional control is between
good and medium
4
Braking deceleration is noticeably
reduced for the wheel braking
effort applied OR directional
control is noticeably reduced
3
Braking deceleration OR
directional control is between
medium and poor
2
Braking deceleration is
significantly reduced for the
wheel braking effort applied OR
directional control is significantly
reduced
1
Braking deceleration is minimal
to non-existent for the wheel
braking effort applied OR
directional control is uncertain
0
TABLE – 6.2 Correlation of runway condition code and pilot reports of runway braking action
6.1.8 Where available, the pilot reports of runway braking action should be taken into consideration
as part of the ongoing monitoring process, using the following principle:
a) a pilot report of runway braking action is taken into consideration for downgrading
purposes; and
b) a pilot report of runway braking action can be used for upgrading purposes only if it is
used in combination with other information qualifying for upgrading.
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6.1.9 Two consecutive pilot reports of runway braking action of POOR shall trigger an assessment
if an RWYCC of 2 or better has been reported.
6.1.10 When one pilot has reported a runway braking action of LESS THAN POOR, the information
shall be disseminated, a new assessment shall be made and the suspension of
operations on that runway shall be considered.
Note 1.― If considered appropriate, maintenance activities may be performed
simultaneously or before a new assessment is made.
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CHAPTER – 7
7. Runway condition assessment matrix (RCAM)
Assigning a runway condition code (RWYCC) Table-5.1, and Correlation of runway condition code
and pilot reports of runway braking action Table-6.2, as given in chapter 5 & 6 when combined will
form the runway condition assessment matrix (RCAM), given below in Table- 7.1.The RCAM is a
tool to be used when assessing runway surface conditions. It is not a standalone document
and shall be used in compliance with the associated procedures of which there are two main
parts:
a) assessment criteria; and
b) downgrade assessment criteria.
Table 7.1 Downgrading or upgrading using a friction measuring device
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RUNWAY CONDITION ASSESSMENT MATRIX (RCAM)
Downgrade assessment criteria
Assessment criteria
Runway
condition
code
(RWYCC)
Runway surface description
Aeroplane deceleration or directional
control
Observation
6
DRY
5
WET (the runway surface is
covered by any visible dampness Braking deceleration is normal for the
or water upto and including 3 mm wheel braking effort applied AND
directional control is normal.
depth)
4
Braking deceleration OR directional
control is between Good and Medium.
GOOD TO
MEDIUM
3
Braking deceleration is noticeably
reduced for the wheel braking effort
applied OR directional control is
noticeably reduced.
MEDIUM
2
WET (“slippery wet” runway)
More than 3 mm depth of
water: STANDING WATER
---
Pilot report of
runway braking
action
---
Braking deceleration OR directional
control is between Medium and Poor.
Braking deceleration is significantly
reduced for the wheel braking effort
applied OR directional control is
significantly reduced.
1
Braking deceleration is minimal to
nonexistent for the wheel braking
effort applied OR directional control is
uncertain.
0
GOOD
MEDIUM TO
POOR
POOR
LESS THAN
POOR
Table 7.2 illustrates an RCAM for an aerodrome which never experiences or
reports snow or ice conditions.
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MODULE-03
CHAPTER-8
8. RUNWAY CONDITION REPORT – Basic information
8.1 The runway condition report (RCR) is used for reporting assessed information.
8.2 When the runway is wholly or partly contaminated by standing water, snow, slush, ice or frost, or
is wet associated with the clearing or treatment of snow, slush, ice or frost, the runway condition
report should be disseminated through the Aeronautical Information Service (AIS) and Air Traffic
Service (ATS). When the runway is wet, not associated with the presence of standing
water, snow, slush, ice or frost, the assessed information should be disseminated using
the runway condition report through the ATS only.
8.3 On a global level, movement areas are exposed to a multitude of climatic conditions and
consequently a significant difference in the condition to be reported. The RCR describes a
basic structure applicable for all these climatic variations. Assessing runway surface
conditions rely on a great variety of techniques and no single solution can apply to every
situation.
8.4 The philosophy of the RCR is that the aerodrome operator assesses the runway surface
conditions whenever water, snow, slush, ice or frost are present on an operational runway.
From this assessment, a runway condition code (RWYCC) and a description of the runway
surface are reported which can be used by the flight crew for aeroplane performance
calculations. This format, based on the type, depth and coverage of contaminants, is the best
assessment of the runway surface condition by the aerodrome operator; however, all other
pertinent information will be taken into consideration and be kept up to date and changes in
conditions reported without delay.
8.5 The syntax for dissemination as described in the RCR template is determined by the operational
need of the flight crew and the capability of trained personnel to provide the information arising
from an assessment.
8.6 The syntax requirement shall be strictly adhered to when providing the assessed information
through the RCR.
8.7 The information to be reported shall be compliant with the RCR which consists of:
a) Aeroplane performance calculation section; and
b) Situational awareness section.
8.8 The information shall be included in an information string in the following order using only AIS
compatible characters:
a) aeroplane performance calculation section:
i) aerodrome location indicator;
ii) date and time of assessment;
iii) lower runway designation number;
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iv) RWYCC for each runway third;
v) percent coverage contaminant for each runway third;
vi) depth of loose contaminant for each runway third;
vii) condition description for each runway third; and
viii) width of runway to which the RWYCCs apply if less than published width.
8.9 A change in the runway surface condition used in the runway condition report is considered
significant whenever there is:
a) any change in the RWYCC;
b) any change in contaminant type;
c) any change in reportable contaminant coverage according to Table-8.1 given
below;
Table 8.1
Assessed per cent
Reported per cent
10 – 25
25
26 – 50
50
51 – 75
75
76 – 100
100
Figure 8.1 Single containment
c) any change in contaminant depth according to Table 8.2 given below;
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Table – 8.2 Depth assessment for contaminants
Contaminant
Valid values to be
reported
Significant change
STANDING
WATER
04, then assessed
value
3 mm up to and
including 15 mm
SLUSH
03, then assessed
value
3 mm up to and
including 15 mm
WET SNOW
03, then assessed
value
5 mm
DRY SNOW
03, then assessed
value
20 mm
e) any other information, for example a pilot report of runway braking action, which
according to assessment techniques used, are known to be significant.
8.10 Reporting, in compliance with the runway condition report, shall commence when a significant
change in runway surface condition occurs due to water, snow, slush, ice or frost.
8.11 Reporting of the runway surface condition should continue to reflect a significant
change until the runway is no longer contaminated. When this situation occurs, the
aerodrome will issue a runway condition report that states the runway is wet or dry as
appropriate.
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CHAPTER- 9
9. Runway Condition Report – (Sections/Example/flow chart/worksheet)
9.1 Aeroplane performance calculation section
9.1.1 The aeroplane performance calculation section is a string of grouped information separated by
a space “ ”and ends with a return and two line feed “≪≡”. This is to distinguish the aeroplane
performance calculation section from the following situational awareness section or the
following aeroplane performance calculation section of another runway.
9.1.2 The information to be included in this section consists of the following.
a) Aerodrome location indicator: a four-letter ICAO location indicator in accordance with
Doc 7910,
Location Indicators.
This information is mandatory.
Format: nnnn
Example: ENZH
b) Date and time of assessment: date and time (UTC) when the assessment was
performed by the trained personnel.
This information is mandatory.
Format: MMDDhhmm
Example: 09111357
c) Lower runway designation number: a two-or three-character number identifying the
runway for which the assessment is carried out and reported.
This information is mandatory.
Format: nn[L] or nn[C] or nn[R]
Example: 09L
d) Runway condition code for each runway third: a one-digit number identifying the
RWYCC assessed for each runway third. The codes are reported in a three-character
group separated by a “/” for each third. The number direction for listing the runway
thirds shall be in the direction as seen from the lower designation.
This information is mandatory.
When transmitting information on runway surface conditions by ATS to flight crews,
the sections are, however, referred to as the first, second or third part of the runway.
The first part always means the first third of the runway as seen in the direction of
landing or take-off as illustrated in Figures 5.1 and 5.2.
Format: n/n/n
Example: 5/5/2
Note 1.― A change in RWYCC from, say, 5/5/2 to 5/5/3 is considered significant.
(See further examples below).
Note 2.― A change in RWYCC requires a complete assessment taking into account
all information available.
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e) Per cent coverage contaminant for each runway third: a number identifying the
percentage coverage.
The percentages are to be reported in an up-to-nine character group separated by a “/” for
each runway third. The assessment is based upon an even distribution within the runway
thirds using the guidance in Table-1.
This information is conditional. It is not reported for one runway third if it is dry or
covered with less than 10 per cent.
Format: [n]nn/[n]nn/[n]nn
Example: 25/50/100
NR/50/100 if contaminant coverage is less than 10% in the first third
25/NR/100 if contaminant coverage is less than 10% in the middle third
25/50/NR if contaminant coverage is less than 10% in the last third
With uneven distribution of the contaminants, additional information is to be given in
the plain language remark part of the situational awareness section of the runway
condition report. Where possible, a standardized text should be used.
Note.― When no information is to be reported, insert “NR” at its
relevant position in the message to indicate to the user that no
information exists (/NR/).
f) Depth of loose contaminant: dry snow, wet snow, slush or standing water for each
runway third: a two or three-digit number representing the assessed depth (mm) of the
contaminant for each runway third.
The depth is reported in a six to nine character group separated by a “/” for each
runway third as defined in Table-8.2. The assessment is based upon an even
distribution within the runway thirds as assessed by trained personnel. If
measurements are included as part of the assessment process, the reported values
are still reported as assessed depths, as the trained personnel have placed their
judgment upon the measured depths to be representative for the runway third.
Format: [n]nn/[n]nn/[n]nn
Examples:
04/06/12 [STANDING WATER]
02/04/09 [SLUSH]
02/05/10 [WET SNOW or WET SNOW ON TOP OF ...]
02/20/100 [DRY SNOW or DRY SNOW ON TOP OF]
NR/NR/100 [DRY SNOW in the last third only]
This information is conditional. It is reported only for DRY SNOW, WET SNOW,
SLUSH and STANDING WATER.
Example of reporting depth of contaminant whenever there is a significant change
1) After the first assessment of runway condition, a first runway condition report is generated.
The initial report is:
5/5/5 100/100/100 02/02/02 SLUSH/SLUSH/SLUSH
Note.― The full information string is not used in this example.
2) With continuing precipitation, a new runway condition report is required to be generated as
subsequent assessment reveals a change in the runway condition code. A second runway
condition report is therefore created as:
2/2/2 100/100/100 03/03/03 SLUSH/SLUSH/SLUSH
3) With even more precipitation, further assessment reveals the depth of precipitation has
increased from 3 mm to 5 mm along the entire length of the runway. However, a new runway
condition report is not required because the runway condition code has not changed (change
in depth is less than the significant change threshold of 3 mm).
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4) A final assessment of the precipitation reveals that the depth has increased to 7 mm. A
new runway condition code is required because the change in depth from the last runway
condition report (second runway condition code) i.e. from 3 mm to 7 mm is greater than the
significant change threshold of 3 mm. A third runway condition report is thus created as
below:
2/2/2 100/100/100 07/07/07 SLUSH/SLUSH/SLUSH
For contaminants other than STANDING WATER, SLUSH, WET SNOW or DRY SNOW, the
depth is not reported. The position of this type of information in the information string is then
identified by /NR/.
Example: /NR/
When the depth of the contaminants varies significantly within a runway third, additional
information is to be given in the plain language remark part of the situational awareness
section of the runway condition report.
g) Condition description for each runway third: The condition type is reported in capital letters by
any of the following condition type descriptions for each runway third and separated by an
oblique stroke “/”.
This information is mandatory.
COMPACTED SNOW
DRY
DRY SNOW
DRY SNOW ON TOP OF COMPACTED SNOW
DRY SNOW ON TOP OF ICE
FROST
ICE
SLUSH
STANDING WATER
WATER ON TOP OF COMPACTED SNOW
WET
WET ICE
WET SNOW
WET SNOW ON TOP OF COMPACTED SNOW
WET SNOW ON TOP OF ICE
Format: nnnn/nnnn/nnnn
Example: DRY SNOW ON TOP OF COMPACTED SNOW/WET SNOW ON TOP OF
COMPACTED SNOW/WATER ON TOP OF COMPACTED SNOW
h) Width of runway to which the RWYCCs apply if less than published width is the
two-digit number representing the width of cleared runway in metres.
This information is optional.
Format: nn
Example: 30
If the cleared runway width is not symmetrical along the centre line, additional
information is to be given in the plain language remark part of the situational
awareness section of the runway condition report.
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9.2 Runway condition report — Situational awareness section:
9.2.1 All individual messages in the situational awareness section end with a full stop sign.
This is to distinguish the message from subsequent message(s). The information to
be included in this section consists of the following:
a) Reduced runway length
This information is conditional when a NOTAM has been published with a new set of
declared distances affecting the LDA.
Format: Standardized fixed text
RWY nn [L] or nn [C] or nn [R] LDA REDUCED TO [n]nnn
Example: RWY 22L LDA REDUCED TO 1450.
b) Drifting snow on the runway
This information is optional.
Format: Standardized fixed text
Example: DRIFTING SNOW.
c) Loose sand on the runway
This information is optional.
Format: RWY nn[L] or nn[C] or nn[R] LOOSE SAND
Example: RWY 02R LOOSE SAND.
d) Chemical treatment on the runway
This information is mandatory.
Format: RWY nn[L] or nn[C] or nn[R] CHEMICALLY TREATED
Example: RWY 06 CHEMICALLY TREATED.
e) Snowbanks on the runway
This information is optional.
Left or right distance in metres from centre line.
Format: RWY nn[L] or nn[C] or nn[R]
SNOWBANK Lnn or Rnn or LRnn FM CL
Example: RWY 06L SNOWBANK LR19 FM CL.
f) Snowbanks on taxiway
This information is optional.
Left or right distance in metres from centre line.
Format: TWY [nn]n SNOWBANK Lnn or Rnn or LRnn FM CL
Example: TWY A SNOWBANK LR20 FM CL.
g) Snowbanks adjacent to the runway penetrating level/profile set in the aerodrome
snow plan.
This information is optional.
Format: RWY nn[L] or nn[C] or nn[R] ADJACENT SNOWBANKS
Example: RWY 06R ADJACENT SNOWBANKS.
h) Taxiway conditions
This information is optional.
Format: TWY [nn]n POOR
Example: TWY B POOR.
i) Apron conditions
This information is optional.
Format: APRON [nnnn] POOR
Example: APRON NORTH POOR.
i)
State-approved and published use of measured friction coefficient
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This information is optional.
Format: [State set format and associated procedures]
Example: [Function of State set format and associated procedures].
k) Plain language remarks using only allowable characters in capital letters where
possible, standardized text should be developed.
This information is optional.
Format: Combination of allowable characters where use of full stop « . » marks the
end of the message.
Allowable characters:
A B C D E F G H I J K LM N O P Q R S T U V W X Y Z
0123456789
/ [oblique stroke] “.” [period]“ ” [space]
Complete information string
An example of a complete information string prepared for dissemination is as follows:
[COM header and Abbreviated header] (Completed by AIS)
GG EADBZQZX EADNZQZX EADSZQZX
070645 EADDYNYX
SWEA0151 EADD 02170055
SNOWTAM 0151
[Aeroplane performance calculation section]
EADD 02170055 09L 5/5/5 100/100/100 NR/NR/NR WET/WET/WET
EADD 02170135 09R 5/4/3 100/50/75 NR/06/06 WET/SLUSH/SLUSH
EADD 02170225 09C 3/2/1 75/100/100 06/12/12 SLUSH/WET SNOW/WET SNOW
[Situational awareness section]
RWY 09L SNOWBANK R20 FM CL. RWY 09R ADJ SNOWBANKS. TWY B POOR.
APRON NORTHPOOR.
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9.3. RUNWAY CONDITION ASSESSMENT PROCESS - FLOW CHARTS:
The generic runway condition assessment process.
Basic RCAM flow chart process
Figure 9.1 The generic runway condition assessment process
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Figure 9.2 Basic RCAM flow chart
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Figure 9.3
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Figure 9.4
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TABLE 9.1 RUNWAY CONDITION REPORT – information and source
Aeroplane performance calculation section
Situational awareness
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RCR Worksheet-1 (wet conditions)
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RCR Worksheet-2 (winter conditions)
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Worksheet for wet conditions:
Example scenarios on how to use the worksheet
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CHAPTER-10
10. PAVEMENT
10.1 FUNCTIONAL REQUIREMENTS
10.1.1 A runway pavement, considered as a whole, is required to fulfil three basic functions as
follows:
a) provide adequate bearing strength;
b) provide good riding qualities; and
c) provide good surface friction characteristics.
Other requirements include:
a) longevity; and
b) ease of maintenance.
The first criterion addresses the structure of the pavement, the second the geometric shape
of the top of the pavement and the third the texture of the actual surface and drainage
when it is wet, texture and slope being the most important friction characteristics of
runway pavement. The fourth and fifth criteria address, in addition to the economic
dimension, the availability of the pavement for aircraft operations.
10.2 DRY RUNWAY
When in a dry and clean state, individual runways generally provide operationally insignificant
differences in friction levels, regardless of the type of pavement and configuration of the surface.
Moreover, the friction level available is relatively unaffected by the speed of the aircraft. Hence,
operation on dry runway surfaces is satisfactorily consistent, and no particular engineering criteria
for surface friction are needed for this case.
10.3 WET RUNWAY
The problem of friction on runway surfaces affected by water can be expressed primarily as a
generalized drainage problem consisting of three distinct criteria:
a) surface drainage (surface shape, slopes);
b) tire/ground interface drainage (macrotexture); and
c) penetration drainage (microtexture).
These three criteria can be significantly influenced by engineering measures and it is
important to note that all of them must be satisfied to achieve adequate friction in all possible
conditions of wetness
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10.4 CONTAMINATED RUNWAY
10.4.1 The problem of friction on runway surfaces affected by contaminants can be expressed
primarily as a generalized maintenance problem consisting of improved interfacial drainage or
removal of the contaminants. The most dominant of these are:
a)
maintenance of improved interfacial drainage
contaminated by water (more than 3 mm in depth);
capability
for
pavements
b) removal of rubber deposits;
c) removal of snow, slush, ice or frost; and
d) removal of other deposits such as sand, dust, mud and oil.
These issues can be significantly influenced by the level of maintenance provided by the airport
operator.
10.4.2 The level of maintenance provided is the capability to remove contaminants as rapidly and
completely as possible to avoid accumulation. The level of maintenance required is a function of
exposure to those contaminants, the maintenance equipment available and the competence of
the personnel operating the maintenance equipment.
10.4.3 Aerodrome operators may be exposed to three main scenarios:
a) wet runway condition scenarios only;
b) snow and ice conditions occur only at irregular intervals and runway closure can be
tolerated to a certain extent as a result of having limited or no removal capability; or
c) snow and ice conditions during which the aerodrome operator must operate as normally as
possible.
10.5 Design - Texture
10.5.1 Surface texture
10.5.1.1 The most important aspect of the pavement surface relative to its friction
characteristics is the surface texture. The effect of different surface material on the tire-toground coefficient of friction arises principally from differences in surface texture. Surfaces are
normally designed with sufficient macrotexture to obtain a suitable water drainage rate
in the tire-runway interface. The texture is obtained by suitable proportioning of the
aggregate/mortar mix or by surface finishing techniques. Pavement surface texture is
expressed in terms of macrotexture and microtexture (see Figure 10-1); however, these are
defined differently depending on the context and measuring technique at hand. Furthermore,
they are understood differently in various parts of the aviation industry.
10.5.1.2 Texture is defined internationally through ISO standards. These standards refer to
texture measured by volume or by profile and expressed as mean texture depth (MTD) or
mean profile depth (MPD). These standards define microtexture to be below 0.5 MPD and
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macrotexture to be above 0.5 MPD. There is no universally agreed relationship between MTD
and MPD.
10.5.2 Microtexture
10.5.2.1 Microtexture is the texture of the individual stones and is hardly detectable by the
eye. Microtexture is considered a primary component in wet skid resistance at slow speeds.
On a wet surface at higher speeds, a water film may prevent direct contact between the
surface asperities and the tire due to lack of drainage from the tire-to-ground contact area.
10.5.2.2 Microtexture is a built-in quality of the pavement surface. By specifying crushed
material that will withstand polishing, microtexture and drainage of thin water films are
ensured for a longer period of time. Resistance against polishing is expressed through the
polished stone value (PSV), which is in principle a value obtained from friction measurement
in accordance with international standards (ASTM D 3319, CEN EN 1097-8).
10.5.2.3 A major problem with microtexture is that it can change within short time periods
without being easily detected. A typical example of this is the accumulation of rubber
deposits in the touchdown area, which will largely mask microtexture without
necessarily reducing macrotexture.
10.6.3 Macrotexture
Macrotexture is the texture between the individual stones. This scale of texture may be judged
approximately by the eye. Macrotexture is primarily created by the size of aggregate used or by
treatment of the surface. Grooving adds to the macrotexture, although how much it adds depends on
width, depth and spacing. Macrotexture is the major factor influencing the tire/ground interface
drainage capacity at high speeds.
Figure 10.1
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10.7 Drainage
Surface drainage is a basic requirement of utmost importance. It serves to minimize water depth on
the surface. The objective is to drain water off the runway in the shortest path possible and
particularly out of the area of the wheel path. Quite obviously, the longer the path that surface water
has to take to exit the runway, the greater the drainage problem will be.
10.8 Rainfall
10.8.1 Rainfall brings moisture to the runway, which will have an effect on aircraft performance.
Flight test data show that even small amounts of water may have a significant effect on aircraft
performance, e.g. damp runways effectively reduce aircraft braking action below that of a clean and
dry runway.
10.8.2 Rainfall on a smooth runway surface affects aircraft performance more than rainfall on a
runway surface with good macrotexture. Rainfall on runway surfaces with good drainage has a
lesser effect on aircraft performance. Grooved runways and runways with PFC surfaces fall into this
category; however, there comes a time when the drainage capabilities of any runway exposed to
heavy or torrential rain can be overwhelmed by water.
10.8.3 At sufficiently high rainfall rates, water will rise above the texture depth. Standing water will
occur, leading to equally hazardous situations as might occur on smooth runways. Improved
performance at such rainfall rates should not be used anymore. For example, a grooved or PFC
runway subject to torrential rainfall might perform worse than a regular smooth, wet runway.
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CHAPTER–11
11. Assessment methods and monitoring trends of change of surface friction
characteristics.
11.1 Assessment methods shown below in Figure 11.1 for monitoring trends of change of
surface friction characteristics. Details are given in tabular form in Tables11.1 to 11.3.
Visual inspections and ruler measurements for human-made
assessment of runway surface contamination
Figure 11.1
Continuous friction measuring equipment (CFME) receiving, presenting and storing data
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ANNEX 14, Volume I, 7th Edition, July
2016
Slope
REMARK
3.1.13 Longitudinal
slopes
3.1.19 Transverse
slopes
Texture
3.1.26 Recommendation.—The
average surface texture depth of a
new surface should be not less than
1.0 mm.
Minimum friction
level set by the
State
3.1.23 A paved runway shall be so
constructed or resurfaced as to
provide surface friction
characteristics at or above the
minimum friction level set by the
State.
The State set criteria for
surface friction
characteristics and output
from State set or agreed
assessment methods form
the reference from which
trend monitoring are
performed and evaluated.
Polishing
3.1.23 A paved runway shall be so
constructed or resurfaced as to
provide surface friction
characteristics at or above the
minimum friction level set by the
State.
Polished Stone Value.
(PSV-value) is a measure of
skidding resistance on a
small sample of stone
surface, having being
subjected to a standard
period of polishing.
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Rubber Geometry Polishing
build-up change
Visual −
macrotexture
Visual assessment will only give a very crude
assessment of the macrotexture. Extensive rubber
build-up can be identified.
X
Visual −
microtexture
Visual assessment will give a very crude
assessment of the microtexture and to what degree
the microtexture has been filled and covered by
rubber.
X
Visual – runway Visual assessment during a rain storm and
geometry
subsequent drying process of the runway will reveal
(ponding)
how the runway drains and if there have been any
changes to runway geometry causing ponding.
Depth of any pond can be measured by a ruler or
any other appropriate depth measurement
method/tool.
X
By touch −
macrotexture
Assessment by touch can differentiate between
degree of loss of texture but not quantifying it.
X
By touch −
microtexture
Assessment by touch can identify if microtexture
has been filled in/covered by rubber build-up.
X
Grease smear
method (MTD)
Measure a volume – Mean Texture Depth (MTD)
primarily by using the grease smear method, is the
measurement method used for research purposes
related to aeroplane performance.
X
Sand (glass)
patch method
(MTD)
Measure a volume – Mean Texture Depth (MTD). The
sand (glass) patch method is not identical to the
grease smear method. There is at present no
internationally accepted relationship between the
two methods.
X
Measure a profile – Mean Profile Depth (MPD). There
is no established relationship between MTD and
MPD. The relationship must be established for the
laser devices used and the preferred volumetric
measurement method used. The relationship must
Laser – moving
be established for the laser devices used and the
(MPD)
preferred volumetric measurement method used.
X
Laser –
stationary
(MPD)
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Rubber
build-up
Friction measurement
– controlled applied
water depth
A friction measurement is a system output
which includes all the surface friction
characteristics and characteristics of the
measuring device itself. All other variables
than those related to the surface friction
characteristics must be controlled in order
to relate the measured values to the
surface friction characteristics.
Geometry
change
X
Polishing
X
The system output is a dimensionless
number which is related to the surface
friction characteristics and as such is also
a measure of macrotexture. (The system
generated number needs to be paired with
other information (assessment methods)
to identify which surface friction
characteristics significantly influence the
system output.)
It is recognized that there is currently no
consensus within the aviation industry on
how to control the uncertainty related to
repeatability, reproducibility and time
stability. It is paramount to keep this
uncertainty as low as possible,
consequently ICAO has tightened the
Standards associated with use of friction
measurement devices, including training
of personnel who operate the friction
measuring devices.
Friction measurement
– natural wet
conditions
Friction measurements performed under
natural wet conditions during a rain storm
might reveal if portions of a runway are
susceptible to ponding and/or to fall below
State set criteria.
Modelling of water
flow and prediction
of water depth
Emerging technologies based on the use
of a model of the runway surface
describing its geometrical surface
(mapped) and paired with sensor
information of water depth allow real-time
information and thus a complete runway
surface monitoring, and anticipation of
water depths.
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11.2 Maintenance of “slippery wet” runway
11.2.1 A wet runway where the surface friction characteristics of a significant portion of the runway
have been determined to be degraded is a slippery wet runway. An appropriate maintenance
programme should ensure adequate drainage, rubber removal and cleaning of runway (non-winter)
contaminants. A trend monitoring concept for runway surface friction characteristics is shown below
in Figure-11.2. The objective is to ensure that the surface friction characteristics for the entire
runway remain at or above the minimum friction level specified by the State.
Figure 11.2 Trend monitoring concept
11.2.2 The trend of degradation of surface friction characteristics of a pavement is monitored in
compliance with criteria specified by the State. Degradation is typically caused by:
a) rubber deposits, which can be managed through a rubber removal programme;
b) surface polishing, which can be managed by monitoring loss of sharpness and are
texturing/resurfacing programme; and
c) poor drainage, which can be managed by monitoring changes in geometry and blocking of
drainage channels and a reshaping programme.
11.2.3 The trend monitoring is used to ensure that the degradation of surface friction characteristics
is above the minimum friction level specified by the State.
11.2.4 In the construction of new runways or resurfacing of existing runways, the construction of
surfaces with adequate slopes and aggregate of angular fragments from crushed gravel or stone to
provide a sharp texture will be essential to ensuring surface friction characteristics that provide good
braking action in wet conditions. The surface friction characteristics of a newly constructed or
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resurfaced runway surface establish the normal starting point for trend monitoring; however, trend
monitoring can also start at any given time through the lifespan of a pavement.
11.2.5 The State-set criteria for surface friction characteristics and output from State-set or agreed
assessment methods form the reference for performing and evaluating trend monitoring. This
reference should ensure that the friction forces that aeroplane certification regulations assume to be
available on wet pavement can be provided by the runway surface.
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MODULE-04
CHAPTER-12
12. Pilot report –AIREP feedback
12.1 The role of the pilot in the runway surface condition reporting process does not end once the
aeroplane safely exits the runway. While the aerodrome operator is responsible for generating the
RWYCC for a runway, pilots are responsible for providing accurate braking action reports. Flight
crew make AIREPs whenever they observe worse runway braking action than previously reported. It
is up to the pilot to assess the manner in which an aircraft responds to the application of wheel
brakes. These reports provide feedback to the aerodrome operator regarding the accuracy of the
assigned RWYCCs relative to the runway surface conditions actually experienced. Table- 12.1
shows the correlation of pilot reports of runway braking action with RWYCCs (this table forms part of
the overall RCAM).
Table12
.1
12.2 Air traffic control (ATC) relays the pilot reports of runway braking action to the aerodrome
operator, who in turn, uses them in conjunction with the RCAM to determine if the RWYCC should
be downgraded until the runway surface condition is improved. These reports thus play an important
part in the cycle of runway surface condition assessment and reporting. Pilots familiar with this
terminology use it when providing controllers with runway braking action reports. If the differences
between two consecutive levels of the categories between “GOOD” (RWYCC 5) and “LESS THAN
POOR” (RWYCC 0) are too subtle for the pilot to detect, the pilot may report on a more coarse scale
of “GOOD”, “MEDIUM” and “POOR”.
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12.3 During periods of increased traffic flow, runway inspection and maintenance may be less
frequent and should be sequenced with aeroplane arrivals. Aerodrome operators may depend on
runway braking action reports to confirm that the runway surface condition is not deteriorating below
the assigned RWYCC. Whenever requested by ATC, or if the assessed runway braking action is
less than previously reported, pilots should provide a braking action report. This is especially
important where the experienced braking action differs from the braking action associated with any
RWYCC currently in effect. When the braking occurrence and the report match up, the pilot and the
aerodrome operator gain additional confidence in the reported runway codes. AIREPs play an
important role in preventing runway excursions as reports of runway braking action below the
assigned RWYCC may influence a subsequent pilot’s decision to continue with a landing. A report
from a preceding aeroplane is all the more reliable when it emanates from another aircraft with
landing performance capabilities similar to his/her own. The pilot is conscious to the fact that even
similar aeroplanes may be operated at a very different mass and approach speed. Aircraft control or
safety should not be jeopardized during taxiing, when communicating the report; pilots provide the
report only when it is safe to do so.
12.4 There can be difficulties in making reports of braking action for the pilot since these reports are
intended to characterize only one of the aeroplane deceleration elements: the availability of wheel
braking. When operating on long dry or wet runways, pilots apply low autobrakes or partial pedal
braking. For most landings, only idle reverse thrust is used. Landing on slippery or contaminated
runways requires a different technique and results in the energy dissipation by the aerodynamic
means, use of reverse thrust, and applied wheel braking, in different proportions than during a
“normal” landing. Aerodynamic drag and reverse thrust are most effective at high speed, and initially
can, by themselves, generate a deceleration rate that can be close to that experienced in nonperformance limited landings.
12.5 The lack of wheel-to-ground friction during the high speed portion of the landing may thus not
be immediately apparent to the pilot, although reduced lateral control due to reduced cornering
forces may be an indicator of reduced wheel-to-ground friction. As the aeroplane decelerates, drag
and reverse thrust become less effective and thrust reversers may be stowed between 70 and 60
kts, in line with manufacturer recommendations for normal landings (they can typically be maintained
extended to full stop if necessary, but when not required to ensure a safe stop, manufacturers
recommend stowage to avoid re-ingestion). During the lower speed portion of the landing, the
deceleration is, to a large extent, created by the wheel brakes. It is consequently in this phase that
the reduced braking action is most noticeable to the pilot. The pilot attempts to characterize the
entire length of runway used during the stop in an AIREP.
12.6 Furthermore, flight crew must understand that a report will only be relevant when the braking
demand has exceeded the braking action available, i.e. the anti-skid system, if installed, has
regulated brake pressure below that commanded by the pilot or the autobrake system, to avoid
skidding and maintain close to optimum slip ratio. The braking is then called “friction limited”. Braking
occurs when the tire is slowed relative to the runway by applying pressure on the brakes. The
maximum braking force occurs when the tire speed is between 7 and 15 per cent slower than the
ground speed of the aeroplane, which is called the slip ratio. On slippery runways the tire may have
a tendency to stop due to lack of friction. Most modern airplanes are equipped with anti-skid systems
that prevent such skidding to occur and optimize the slip ratio for maximum braking. Friction-limited
braking thus occurs when the pilot, or the anti-skid system when available, must adjust brake
pressure to avoid skidding. There is usually no indication in the cockpit to inform the pilot that the
anti-skid system is cycling. Skidding may not occur on all wheels simultaneously.
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12.7 Flight crew communicates the sections of runway in which wheel braking was applied and/or
directional control difficulties were encountered, e.g. “Braking Action Medium on last third of runway
08” or “Braking Action Poor on high-speed exit Bravo Runway 20.”
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CHAPTER-13
13. Aircraft runway performance implications - Landing and takeoff considerations
13.1 It is obvious that as soon as the runway condition deviates from the ideal dry and clean state,
the acceleration and deceleration capabilities of the aircraft may be affected negatively with a direct
impact on the required take-off, accelerate-stop and landing distances. Reduced friction also impairs
directional control of the aircraft, and therefore the acceptable crosswind during take-off and landing
will be reduced.
13.2 Qualitative assessment
13.2.1 Qualitatively, the impacts on the aircraft’s maximum braking capability can be summarized as
follows:
a) wet and solid contaminants:
1) acceleration and hence take-off distance not affected; and
2) reduced braking capability, longer accelerate-stop and landing distances.
b) loose contaminants:
1) acceleration capability reduced by displacement and impingement drag (slush, wet
snow and standing water) or the force required to compress the contaminant (dry
snow); and
2) deceleration capability reduced by lower friction, aquaplaning at high speeds,
partially compensated by displacement and impingement drag.
As a result:
a) take-off distance is longer (worse when the contaminant is deeper);
b) accelerate-stop distance is longer (less so when the contaminant is deeper
because of higher displacement and impingement drag); and
c) landing distance is longer (less so when the contaminant is deeper because of
higher displacement and impingement drag).
13.3 Quantitative assessment
13.3.1 Quantitatively, the following data provide the order of magnitude of the effects of runway
conditions on the actual performance of a typical medium-size aircraft, the reference being dry
conditions (accelerate-stop distance effects assume take-off rejection at the same V1 speed, and the
braked ground phase is calculated with maximum pedal braking). It should be mentioned that the
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impact on regulatory performance may be different because the regulatory calculation rules are
dependent upon runway conditions.
a) Wet conditions (no reversers):
1) acceleration and continued take-off are not affected;
2) the accelerate-stop distance is increased by approximately 20 to 30 per cent. A
grooved or PFC runway will reduce this penalty to approximately 10 to 15 per cent;
Note.— Use of reverse thrust (one engine inoperative) will reduce this effect by 20 to
50 per cent depending on the effectiveness of the reversers and runway
conditions.
3) the braked landing ground phase is increased by 40 to 60 per cent on a smooth
runway and 20 per cent on a grooved or PFC runway.
Note.— Use of all-engine reverse thrust will reduce this effect by
approximately 50 per cent depending on the effectiveness of the reversers
and runway conditions.
b) 13 mm of water or slush-covered conditions:
1) the take-off distance is increased by 10 to 20 per cent with all engines operating
due to displacement and impingement drag;
Note.— The effect on the one engine inoperative take-off distance will be significantly
larger.
2) the accelerate-stop distance will increase by 50 to 100 per cent, reduced to a 30 to
70 per cent increase with the use of thrust reversers (one engine inoperative); and
3) the braked landing ground phase is increased by 60 to 100 per cent depending on
the actual depth of the water or slush on the runway. This can be reduced significantly
by the use of reverse thrust.
c) Compact snow:
1) acceleration and continued take-off are not affected;
2) the accelerate-stop distance is increased by 30 to 60 per cent, reduced to 20 to 30
per cent with the use of thrust reversers (one engine inoperative); and
3) the braked landing ground phase may increase by 60 to 100 per cent. Even with
the use of reverse thrust, this may be as much as 1.4 to 1.8 times the dry runway
distance.
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d) Non-melting ice conditions:
1) the effect of non-melting ice conditions can vary considerably depending on the
smoothness of the surface, whether it has been treated with sand or melting agents,
etc.;
2) acceleration and continued take-off are not affected;
3) the accelerate-stop distance may vary from almost as good as compact snow to a
level approaching wet ice conditions;
4) the braked landing ground phase may increase by distances from the values noted
for compact snow to distances approaching the wet ice conditions noted below.
e) Wet ice conditions:
1) acceleration and continued take-off are not affected;
2) the accelerate-stop distance is more than doubled, even with the use of thrust
reversers; and
3) the braked landing ground phase may increase by a factor of 4 to 5. Even with the
use of reverse thrust, this may be as much as 3 to 4 times the dry runway distance.
13.3.2 Wet ice conditions correspond to a braking action reported as “nil”, and operations should not
be conducted due to the performance impacts discussed above and the potential for loss of
directional control of the aircraft.
13.3.3 As a summary, Figures 13.1 to 13.3 provide a visual indication of the impact of the severity of
runway conditions on take-off distance, accelerate-stop distance and the landing ground phase for a
typical medium-size aircraft with thrust reversers of average efficiency. The typical effect of a wet,
skid-resistant surface (e.g. PFC or grooved) is also provided.
Figure 13.1 Impact of the runway condition on actual take-off distance (all engines operative)
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Figure 3.2 Impact of the runway condition on accelerate-stop distance
Figure 13.3 Impact of the runway condition on the landing ground phase
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CHAPTER-14
14. Dissemination of information
14.1 Aviation stakeholder’s activities and communication chain for the dissemination of information is
given below in figure-14.1.
Airlines companies
Air traffic control & aeronautical information
serviceaeromauticaeronautical information
servicw
Approaching aircraft
Aircraft manufactures
Weather services
Runway inspectors
Airport operator
Regulatory authorities
Supervisory authority
Landed aircraft
Figure 14.1 Communication chain for the dissemination of information
14.2 Information on the condition of the movement area and the operational status of related
facilities shall be provided to the appropriate aeronautical information services (AIS) units, and
similar information of operational significance to the ATS units, to enable those units to provide the
necessary information to arriving and departing aircraft. The information shall be kept up-to-date and
changes in conditions reported without delay.
14.3 Information on the runway surface condition includes the runway surface friction characteristics,
which are assessed according to the aerodrome maintenance programme, the presence of water,
snow, slush, ice or other contaminants on the runway, as well as the RWYCC in operational
conditions.
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14.4 ICAO’s methods of reporting and promulgating information are as follows:
a) aeronautical information publications (AIPs);
b) aeronautical information circulars (AICs);
c) notice to airmen (NOTAM);
d) SNOWTAM; (see table-14-1)
e) AIREPs;
f) automatic terminal information services (ATIS); and
g) air traffic control (ATC) communications.
14.5 The increasing use of ground/air-ground data link and computerized systems, both on board
the aircraft and on the ground, is being progressively supplemented with digitized information.
14.6 Currently, PANS-AIM still requires, inter alia, a description to be provided in the AIP of the type
of friction measuring device used, although it is accepted that those values cannot be related to
aircraft performance. In addition, the runway surface friction characteristics are required to be
described in the AIP, AICs and NOTAMs. For winter operations, a brief description of the snow plan
is also required to be promulgated in the AIP.
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Table 14.1 The SNOWTAM template
AEROPLANE PERFORMANCE CALCULATION SECTION
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SITUATIONAL AWARENESS SECTION
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INSTRUCTIONS FOR THE COMPLETION OF THE SNOWTAM FORMAT
1. General
a) When reporting on more than one runway, repeat Items B to H (aeroplane performance
calculation section).
b) The letters used to indicate items are only used for reference purpose and should not be
included in the messages. The letters, M (mandatory), C (conditional) and O (optional) mark
the usage and information and shall be included as explained below.
c) Metric units shall be used and the unit of measurement not reported.
d) The maximum validity of SNOWTAM is 8 hours. New SNOWTAM shall be issued whenever a
new runway condition report is received.
e) A SNOWTAM cancels the previous SNOWTAM.
f) The abbreviated heading “TTAAiiii CCCC MMYYGGgg (BBB)” is included to facilitate the
automatic processing of SNOWTAM messages in computer data banks. The explanation of
these symbols is:
TT
= data designator for SNOWTAM = SW;
AA
= geographical designator for States, e.g. LF = FRANCE, EG = United Kingdom (see
Location Indicators (Doc 7910), Part 2, Index to Nationality Letters for Location Indicators);
iiii
= SNOWTAM serial number in a four-digit group;
CCCC = four-letter location indicator of the aerodrome to which the SNOWTAM refers (see
Location Indicators (Doc 7910));
MMYYGGgg = date/time of observation/measurement, whereby:
MM = month, e.g. January = 01, December = 12
YY = day of the month
GGgg = time in hours (GG) and minutes (gg) UTC;
(BBB) = optional group for correction, in the case of an error, to a SNOWTAM message
previously disseminated with the same serial number = COR.
Note 1.— Brackets in (BBB) are used to indicate that this group is optional.
Note 2.— When reporting on more than one runway and individual dates/times of
observation/assessment are indicated by repeated Item B, the latest date/time of
observation/assessment is inserted in the abbreviated heading (MMYYGGgg).
Example: Abbreviated heading of SNOWTAM No.
measurement/observation of 7 November at 0620 UTC:
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SWLS0149 LSZH 11070620
Note.— The information groups are separated by a space, as illustrated above.
g) The text “SNOWTAM” in the SNOWTAM Format and the SNOWTAM serial number in a four-digit
group shall be separated by a space, for example: SNOWTAM 0124.
h) For readability purposes for the SNOWTAM message, include a line feed after the SNOWTAM
serial number, after Item A, and after the aeroplane performance calculation section.
i) When reporting on more than one runway, repeat the information in the aeroplane performance
calculation section from the date and time of assessment for each runway before the information
in the situational awareness section.
j)
Mandatory information is:
1)
AERODROME LOCATION INDICATOR;
2)
DATE AND TIME OF ASSESSMENT;
3)
LOWER RUNWAY DESIGNATOR NUMBER;
4)
RUNWAY CONDITION CODE FOR EACH RUNWAY THIRD; and
5)
CONDITION DESCRIPTION FOR EACH RUNWAY THIRD (when runway condition
code (RWYCC) is reported 1–5)
2. Aeroplane performance calculation section
Item A — Aerodrome location indicator (four-letter location indicator).
Item B — Date and time of assessment (eight-figure date/time group giving time of observation as
month, day, hour and minute in UTC).
Item C — Lower runway designator number (nn[L] or nn[C] or nn[R]).
Note.—Only one runway designator is inserted for each runway and always the lower
number.
Item D — Runway condition code for each runway third. Only one digit (0, 1, 2, 3, 4, 5 or 6) is
inserted for each runway third, separated by an oblique stroke (n/n/n).
Item E— Per cent coverage for each runway third. When provided, insert 25, 50, 75 or 100 for each
runway third, separated by an oblique stroke ([n]nn/[n]nn/[n]nn).
Note 1.— This information is provided only when the runway condition for each runway third
(Item D) has been reported as other than 6 and there is a condition description for each
runway third (Item G) that has been reported other than DRY.
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Note 2.— When the conditions are not reported, this will be signified by the insertion of “NR”
for the appropriate runway third(s).
Item F — Depth of loose contaminant for each runway third. When provided, insert in millimetres for
each runway third, separated by an oblique stroke (nn/nn/nn or nnn/nnn/nnn).
Note 1.— This information is only provided for the following contamination types:
— standing water, values to be reported 04, then assessed value. Significant changes
3 mm up to and including 15 mm;
— slush, values to be reported 03, then assessed value. Significant changes 3 mm
up to and including 15 mm;
— wet snow, values to be reported 03, then assessed value. Significant changes 5
mm; and
— dry snow, values to be reported 03, then assessed value. Significant changes 20
mm.
Item G — Condition description for each runway third. Insert any of the following condition
descriptions for each runway third, separated by an oblique stroke.
COMPACTED SNOW
DRY SNOW
DRY SNOW ON TOP OF COMPACTED SNOW
DRY SNOW ON TOP OF ICE
FROST
ICE
SLUSH
STANDING WATER
WATER ON TOP OF COMPACTED SNOW
WET
WET ICE
WET SNOW
WET SNOW ON TOP OF COMPACTED SNOW
WET SNOW ON TOP OF ICE
DRY (only reported when there is no contaminant)
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Note.—When the conditions are not reported, this will be signified by the insertion of
“NR” for the appropriate runway third(s).
Item H — Width of runway to which the runway condition codes apply. Insert the width in metres if
less than the published runway width.
3.
Situational awareness section
Note 1.— Elements in the situational awareness section end with a full stop.
Note 2.— Elements in the situational awareness section for which no information
exists, or where the conditional circumstances for publication are not fulfilled, are left
out completely.
Item I — Reduced runway length. Insert the applicable runway designator and available length in
meters (example: RWY nn [L] or nn [C] or nn [R] REDUCED TO [n]nnn).
Note.— This information is conditional when a NOTAM has been published with a
new set of declared distances.
Item J — Drifting snow on the runway, when reported, insert “DRIFTING SNOW”.
Item K — Loose sand on the runway. When loose sand is reported on the runway, insert the lower
runway designator and with a space “LOOSE SAND” (RWY nn or RWY nn[L] or nn[C] or
nn[R] LOOSE SAND).
Item L — Chemical treatment on the runway. When chemical treatment has been reported applied,
insert the lower runway designator and with a space “CHEMICALLY TREATED” (RWY nn
or RWY nn[L] or nn[C] or nn[R] CHEMICALLY TREATED).
Item M — Snow banks on the runway. When snow banks are reported present on the runway, insert
the lower runway designator and with a space “SNOW BANK” and with a space left “L”
or right “R” or both sides “LR”, followed by the distance in metres from centre line
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separated by a space FM CL (RWY nn or RWY nn[L] or nn[C] or nn[R] SNOW BANK
Lnn or Rnn or LRnn FM CL).
Item N — Snow banks on a taxiway. When snow banks are present on a taxiway, insert the taxiway
designator and with a space “SNOW BANK” (TWY [nn]n SNOW BANK).
Item O — Snow banks adjacent to the runway. When snow banks are reported present penetrating
the height profile in the aerodrome snow plan, insert the lower runway designator and
“ADJ SNOW BANKS” (RWY nn or RWY nn[L] or nn[C] or nn[R] ADJ SNOW BANKS).
Item P —Taxiway conditions. When taxiway conditions are reported as poor, insert the taxiway
designator followed by a space “POOR” (TWY [n or nn] POOR or ALL TWYS POOR).
Item R— Apron conditions. When apron conditions are reported as poor, insert the apron designator
followed by a space “POOR” (APRON [nnnn] POOR or ALL APRONS POOR).
Item S — Measured friction coefficient, where reported, insert the measured friction coefficient and
friction measuring device.
Note.— This will only be reported for States that have an established
programme of runway friction measurement using a State-approved friction
measuring device.
Item T — Plain language remarks.
EXAMPLE OF COMPLETED SNOWTAM FORMAT
Example SNOWTAM 1
GG EADBZQZX EADNZQZX EADSZQZX
170100 EADDYNYX
SWEA0149 EADD 02170055
(SNOWTAM 0149
EADD
02170055 09L 5/5/5 100/100/100 NR/NR/03 WET/WET/WET SNOW)
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Example SNOWTAM 2
GG EADBZQZX EADNZQZX EADSZQZX
170140 EADDYNYX
SWEA0150 EADD 02170135
(SNOWTAM 0150
EADD
02170055 09L 5/5/5 100/100/100 NR/NR/03 WET/WET/WET SNOW
02170135 09R 5/2/2 100/50/75 NR/06/06 WET/SLUSH/SLUSH
Example SNOWTAM 3
GG EADBZQZX EADNZQZX EADSZQZX
170229 EADDYNYX
SWEA0151 EADD 02170225
(SNOWTAM 0151
EADD
02170055 09L 5/5/5 100/100/100 NR/NR/03 WET/WET/WET SNOW
02170135 09R 5/2/2 100/50/75 NR/06/06 WET/SLUSH/SLUSH
02170225 09C 2/3/3 75/100/100 06/12/12 SLUSH/WET SNOW/WET SNOW
RWY 09L SNOW BANK R20 FM CL. RWY 09R ADJ SNOW BANKS. TWY B POOR.
APRON NORTH POOR
Example SNOWTAM 4
GG EADBZQZX EADNZQZX EADSZQZX
170350 EADDYNYX
SWEA0152 EADD 02170345
(SNOWTAM 0152
EADD
02170345 09L 5/5/5 100/100/100 NR/NR/03 WET/WET/SLUSH
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02170134 09R 5/2/2 100/50/75 NR/06/06 WET/SLUSH/SLUSH
02170225 09C 2/3/3 75/100/100 06/12/12 SLUSH/WET SNOW/WET SNOW 35
DRIFTING SNOW.RWY 09L LOOSE SAND. RWY 09R CHEMICALLY TREATED. RWY 09C
CHEMICALLY TREATED.)
14.7 Aeronautical information publication (AIP)
14.7.1 Friction issues in the AIP are related to:
a) runway physical characteristics; and
b) the snow plan.
14.7.2 As per AD 1.2.2, a brief description should be given of general snow plan considerations for
aerodromes and heliports available for public use at which snow conditions are normally liable to
occur. Related friction issues include:
a) measuring methods and measurements taken;
b) system and means of reporting;
c) cases of runway closure; and
d) distribution of information about snow, slush or ice conditions.
14.8 Aeronautical information circular (AIC)
14.8.1 An AIC should be originated whenever it is necessary to promulgate aeronautical information
that does not qualify for inclusion in an AIP or a NOTAM. Related friction issues include the advance
seasonal information on the snow plan.
14.9 Notice to airmen (NOTAM)
14.9.1 A NOTAM should be originated and issued promptly whenever information to be distributed is
of a temporary nature and of short duration or when operationally significant permanent changes or
temporary changes of long duration are made at short notice.
14.9.2 This applies to the friction issues related to the:
a) physical characteristics published in the AIP; and
b) presence or removal of, or significant changes in, hazardous conditions due to snow,
slush, ice or water on the movement area.
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14.10 DATA GATHERING AND INFORMATION PROCESSING
14.10.1 Several automated systems are becoming available to provide a remote indication of runway
surface conditions, while others are still under development. At present, these systems are not in
widespread use, and systems that provide an accurate indication of braking action seem a long way
off. This unavailability strongly affects the related communication process.
14.10.2 Consequently, aerodrome operators need to gather relevant data, process the related
information using manual systems and make information available to users using conventional ways
that require a considerable amount of time in addition to the need to obtain access to runways,
which is often difficult, particularly at busy aerodromes.
14.10.3 Presently, the primary means of communication are ATIS and ATC, in addition to
SNOWTAM.
14.11 Automatic terminal information service (ATIS)
14.11.1 An ATIS presents a very important means of transmitting information, relieving operational
personnel from the routine duty of transmitting runway conditions and other relevant information to
the flight crew. In addition to normal operational and weather information, the following information
about the runway condition should be mentioned whenever the runway is not dry (RWYCC 6):
14.11.1.1 Aeroplane performance section:
a) operational runway in use at time of issuance;
b) RWYCC for the operational runway, for each runway third in the operational
direction;
c) condition description, coverage and depth (for loose contaminants);
d) width of the operational runway to which the RWYCC applies, if less than the
published width; and
e) reduced length, if less than the published length.
14.11.1.2 Situational awareness section:
f) drifting snow;
g) loose sand;
h) operationally significant snowbanks;
i) runway exits, taxiways and apron if POOR; and
j) any other pertinent information in short, plain language.
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14.11.2 One inherent weakness in the ATIS system is the currency of the information. This is due to
the fact that flight crews generally listen to ATIS on arrival, some twenty minutes before landing, and
in rapidly changing weather, the runway conditions may alter dramatically in such a time span.
14.12 Air traffic control (ATC)
14.12.1 The organization responsible for gathering data and processing information of operational
significance relating to runway conditions usually transmits such information to ATC, and ATC, in
turn, provides this information to the flight crew if different from the ATIS. At present, this procedure
appears to be the only one that is able to provide timely information to the flight crew, especially in
rapidly changing conditions.
14.12.2 In addition to being timely, information disseminated through ATC may contain additional
information associated with weather observed and forecasted by meteorological (MET) personnel,
even before it is available on ATIS, as well as information gathered by other flight crews, such as
braking action reports. This arrangement provides pilots with the best possible information available
within the current system for sound decision-making.
14.12.3 Finally, where visibility conditions and aerodrome configuration permit, ATC can provide the
flight crew, at very short notice, with their own immediate observations, such as a rapid change in
rainfall intensity or the presence of snow, notwithstanding that this may be considered as unofficial
information.
14.13 Communication network
14.13.1 Air-ground communication between the flight deck and ATS has generally been conducted
through radiotelephony speech but large areas remain beyond the high frequency (HF) or very high
frequency (VHF) coverage.
14.13.2The burden of voice communication and the saturation of present ATC capabilities have
created a strong demand for automated ATS transmission of which digital data link has become a
key element. Therefore, in the near future, service providers and users will need to adapt their
ground communications systems to international data link requirements.
14.14 DIGITAL NOTAM
14.14.1 A transition strategy is being developed to ensure the availability of real-time accredited and
quality assured aeronautical information to any air traffic management (ATM) user in a globally
interoperable and fully digital environment. It is recognized that to satisfy new requirements arising
from the Global ATM Operational Concept, AIS must transition to the broader concept of
aeronautical information management (AIM).
14.14.2 One of the most innovative data products that will be based on the standard aeronautical
data exchange model is a digital NOTAM that will provide dynamic aeronautical information to all
stakeholders with an accurate and upto-date common representation of the aeronautical
environment in which flights are operated. The digital NOTAM is defined as a data set that contains
the information included in a NOTAM in a structured format which can be fully interpreted by an
automated computer system for accurate and reliable updating of the aeronautical environment, both
for automated information equipment and humans.
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Attachment ATT-1
Runway excursions are a frequent occurrence annually. The following list includes runway
excursions which are notable because they resulted in fatalities, destruction of the aircraft, or
substantial aviation safety changes or improvements.
Event
Year
Location
Description
To avoid a runway overrun and collision with
the approach light system, the captain of
a Boeing 747-400 deliberately veered the
plane off the left side of the runway and
into Victoria Harbour. No one was killed, but
the plane was written off as a hull loss.
China
Airlines
Flight 605
1993
Philippine
Airlines
Flight 137
The Airbus A320-214 overran the runway due
to pilot error and crashed into a residential
area. There were no fatalities out of the 130
Bacolod
City
Domestic
1998
passengers and crew on board the aircraft,
Airport, Bacolod, Philippines
but three people on the ground were killed,
and there were many injuries. The aircraft was
written off as a loss.[8]
American
Airlines
Flight 1420
Little
Rock
1999 Airport, Little Rock,
U.S.
Southwest
Airlines
Flight 1455
A Boeing 737-300 landed too fast to stop on a
wet runway, crashed through a perimeter wall
Bob Hope Airport, Burbank,
2000
and came to a stop near a gas station.
California, U.S.
Everyone survived, but due to structural
damage the aircraft was written off.
Kai Tak Airport, Hong Kong
A McDonnell Douglas MD-82 overran the
National
runway, crashed into an approach lighting
Arkansas,
structure, and broke apart, killing 11 of the
145 occupants.
While landing in wet weather, the McDonnell
Douglas MD-82 overran the runway due to
hydroplaning and poor aircraft braking
Lion
Air
Adisumarmo
International
2004
performance. After leaving the runway, the
Flight 583
Airport, Surakarta, Indonesia
aircraft struck an embankment and split into
two sections. 25 of the 153 people on board
were killed.
Southwest
Airlines
Flight 1248
A Boeing 737-700 overran the runway while
Midway
International landing in a snowstorm and crashed into
2005
Airport, Chicago, Illinois, U.S.
automobile traffic, killing one person on the
ground.
An Airbus A340 overran the end of the runway
Toronto
Pearson
Air France
and came to rest in a ravine. 43 people were
2005 International
Flight 358
injured, and the aircraft was destroyed by a
Airport, Toronto, Canada
post-crash fire.
The Airbus A310 overshot the runway and
struck a concrete barrier at high speed,
S7 Airlines
Irkutsk
International
2006
causing the aircraft to break apart and igniting
Flight 778
Airport, Irkutsk, Russia
a massive fire. 125 of the 203 occupants were
killed.
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Garuda
Indonesia
Flight 200
During landing, the Boeing 737-400 departed
Adisutjipto
International the runway, crashed into a rice field and burst
2007
into flames. Of the 140 occupants, 21 were
Airport, Yogyakarta, Indonesia
killed.
TAM
Airlines
Flight 3054
An Airbus A320 overran the runway while
São
Paulo–Congonhas landing in rain, and crashed into a warehouse.
2007
All 187 people on board, and 13 people on the
Airport, São Paulo, Brazil
ground, were killed.
Sriwijaya Air
2008
Flight 62
Sultan Thaha Airport, Jambi
The Boeing 737-200 overran the runway due
to a hydraulics malfunction of the aircraft and
crashed into a house. There were no fatalities
out of the 130 passengers and crew on board
the aircraft, but one person inside the house
was killed. The aircraft received substantial
damage and was written off. [9]
American
Airlines
Flight 331
A Boeing 737-800 landing in rain and a
tailwind touched down more than 4,000 feet
from the start of the runway. Unable to stop in
Norman Manley International
2009
the remaining distance, it broke apart on rocks
Airport, Kingston, Jamaica
near the shoreline. No one was killed, but 85
people were injured and the plane was
destroyed.
Air India
Express
Flight 812
The Boeing 737-800 overshot the end of the
runway, went through a 300 feet (91 m) sand
Mangalore
International
2010
arrestor bed meant as excursion protection,
Airport, Mangalore, India
then slid down a steep hillside. 158 of the 166
occupants were killed.
Caribbean
Airlines
Flight 523
A Boeing 737-800 overran the runway while
attempting to land in rainy weather. All
CheddiJagan
International
2011
occupants survived, but the aircraft was
Airport, Georgetown, Guyana
irreparably damaged and seven people were
injured.
Pegasus
Airlines
Flight 8622
Trabzon
2018
Airport, Trabzon, Turkey
Pegasus
Airlines
Flight 2193
A Boeing 737-800 overran the runway while
SabihaGökçen International
landing in heavy rain and high winds, and
2020 Airport, Istanbul, Turkey
broke into several pieces. 3 of the 183 people
aboard were killed.
Air India
Express
Flight 1344
A Boeing 737-800 ran off the left side of the
runway during landing and slid down a cliff,
stopping short of the water. No one was killed,
but the aircraft was destroyed.
A Boeing 737-800 overran the tabletop
runway, skidding off the end of the runway
2020
Calicut
International and crashing into a gorge. The aircraft was
carrying 190 people including 6 crew
Airport, Kerala, India
members. A total of 20 people, including both
pilots, were killed in the crash.
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Bibliography:
ICAO

Annex 14 — Aerodromes

Procedures for Air Navigation Services (PANS)

(Volume I — Aerodrome Design and Operations)

ATM — Air Traffic Management (Doc 4444)

Aerodromes (Doc 9981)

AIM — Aeronautical Information Management (Doc 10066)

Airport Services Manual (Doc 9137)
Manual


Part 2 — Pavement Surface Conditions

Aeroplane Performance Manual (Doc 10064)

CIR355 - Assessment, Measurement and Reporting of Runway
Surface Conditions
Circular
FAA

TALPA ARC working group recommendations
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