Flight Training Division
Handout
RNAV
Basics, IFR, G1000
RNAV
RNAV Basics
Basics
„ IFR
„ G1000
„
© Peter Schmidleitner
© Peter Schmidleitner
What is “RNAV” ?
„
How does
it work ?
„
© Peter Schmidleitner
„
„
„
„
RNAV developed to provide more
lateral freedom
Better use of airspace
Route not tied to fly-over navigation
aids
Initially RNAV commonly meant VOR
based rho-theta RNAV systems
Expanded to also include INS/IRS,
OMEGA, LORAN C, Doppler, DME/DME
and GNSS
© Peter Schmidleitner
a method of navigation that permits
aircraft operation on any desired
course within the coverage of stationreferenced navigation signals or within
the limits of a self contained system
capability, or a combination of these.
© Peter Schmidleitner
History of RNAV
Why RNAV ?
„
Area Navigation (RNAV)
„
„
„
„
Use of RNAV began in late 1960’s
Most were VOR/DME RNAV systems
(for GA types; INS for large air carriers)
System used waypoints based on
radial/DME from VOR/DME facilities
(“Ghost VORs”)
Maximum distance WP from facility was
approximately 40 NM
© Peter Schmidleitner
1
History of RNAV
„
History of RNAV
Early VOR/DME RNAV system
KNS 80 track line computer
Rho-Theta RNAV Route
No database
support required
yet!
© Peter Schmidleitner
© Peter Schmidleitner
History of RNAV
„
History of RNAV
Pilots started to complain:
„ „Why do we have to input the
same data every day? Can‘t you
store the data somewhere in the
equipment?“
„
„
„
© Peter Schmidleitner
„
1972 (?) LITTON INS had database of
facilities
June 1973, National Air DC-10 equipped
with Collins ANS-70 conducted RNAV
operation, including approaches in
VMC, with database
© Peter Schmidleitner
KLM/SwissAir/SAS/UTA had a cooperative effort
Swissair became responsible for the
development of a database to support
this effort
© Peter Schmidleitner
History of RNAV
„
Some airlines began exploring
RNAV systems
Why a „Database“ ?
„
„
Reason 1:
To store permanent data, avoiding
repetitive input of the same data
© Peter Schmidleitner
2
Why a „Database“ ?
„
„
Reason 2:
RNAV System is able to determine
position relative to the earth‘s
surface
„
„
But:
It has to know the position of other
points to be able to „navigate“
„
„
Responsibilities
Therefore:
A „Directory of navigational fixes“
(„Database“) is necessary
© Peter Schmidleitner
© Peter Schmidleitner
Responsibilities
Responsibilities
© Peter Schmidleitner
© Peter Schmidleitner
Responsibilities
Database Revision Cycle
„
28 Days (AIRAC Cycle) *)
„
„
„
© Peter Schmidleitner
Cutoff date:
Usually 21 days before the
„effective date“
*) AIRAC: Aeronautical Information
Regulation And Control
© Peter Schmidleitner
3
RNAV today:
„
Garmin GNS 430, 530
2 main groups of equipment:
„
„Panel mounted GPS“
„
„
(„stand alone“)
FMS (Flight Management Systems)
„
(„multi-sensor“)
© Peter Schmidleitner
Garmin G1000
© Peter Schmidleitner
How does „database“ RNAV work?
A common misunderstanding:
1. RNAV system determines
position of ACFT
2. RNAV system then shows
ACFT position in the database
map
NO !
© Peter Schmidleitner
How does „database“ RNAV work?
© Peter Schmidleitner
How does „database“ RNAV work?
It is like this:
1. The „reference system“ (grid,
coordinates) ist „fixed“ to it‘s
„reference points“ (e.g. DMEs,
sattelites, etc.)
2. RNAV system determines
position of ACFT in relation to
the „reference system“
© Peter Schmidleitner
3. RNAV System overlays
graphic of database map in
relation to the aircraft
position
4. If aircraft position was
correct, then the database
map corresponds to the „real
world“
© Peter Schmidleitner
4
How to detect a map shift ?
„
Compare RNAV data with „raw data“
„
„
„
„
„
best method: compare DME distances
e.g.:
if you have a VOR/DME location as a WPT,
select same VOR/DME as „NAV“-source,
compare „Dist to WPT“ with „DME reading“
WGS 84
© Peter Schmidleitner
© Peter Schmidleitner
WGS 84
„
„
„
The earth is not a perfect sphere
Mathematically simplyfied: an
„Ellipsoid of rotation“
By projecting this curved surface to
a flat topographical map distortions
are created
WGS 84
„
Distortions are minimized by using
local parameters for the ellisoid
© Peter Schmidleitner
© Peter Schmidleitner
WGS 84
„
„
Therefore: many different
reference systems („map datum“)
A specific point will have different
„coordinates“ in different
reference systems
© Peter Schmidleitner
WGS 84
„
GPS is based on the reference
system WGS 84
„
„
Therefore:
All coordinates must be published
according to „WGS 84“
© Peter Schmidleitner
5
RAIM
RAIM
Receiver Autonomous
Integrity Monitoring
© Peter Schmidleitner
© Peter Schmidleitner
RAIM
RAIM
„
What is „Integrity“?
The ability of a system to provide timely
warnings to users when the system
should not be used for navigation
„
„
„
© Peter Schmidleitner
RAIM
„
„
5 SATs necessary for RAIM
(4 with baro-aid) (G1000: no baro-aid)
SAT geometry must allow accuracy of
„
„
„
„
4 NM oceanic
2 NM e-route
1 NM terminal
0,3 NM approach
© Peter Schmidleitner
Monitors and verifies integrity and
geometry of satellite
Notifies pilot if SATs are not providing
necessary coverage
Predicts SAT coverage at DEST
G1000: Eliminates corrupt satellites from
navigation (FDE)
© Peter Schmidleitner
RAIM
RAIM not available at FAF:
Missed Approach !
© Peter Schmidleitner
6
RAIM
„
3 „abnormal situations“ in connection
with RAIM:
„
„
„
RAIM
„
RAIM gives a „position warning“
RAIM declares itself „not available“
RAIM prediction negative
3 „abnormal situations“ in connection
with RAIM:
„
„
„
RAIM gives a „position warning“
RAIM declares itself „not available“
RAIM prediction negative
On G1000:
© Peter Schmidleitner
Annunciation
HSI
POSN ERROR
WARN
© Peter Schmidleitner
RAIM
„
3 „abnormal situations“ in connection
with RAIM:
„
„
„
RAIM gives a „position warning“
RAIM declares itself „not available“
RAIM prediction negative
On G1000:
Annunciation
HSI
INTEG RAIM
INTEG
FDE
© Peter Schmidleitner
© Peter Schmidleitner
FDE
FDE
„
Fault Detection and
Exclusion
© Peter Schmidleitner
„
Fault Detection:
detects presence of unacceptable large
error
Fault Exclusion:
excludes source of unacceptable large
error
© Peter Schmidleitner
7
FDE
„
FDE
6 SATs necessary to eliminate
corrupt SAT
(5 with baro-aid) (G1000: no baro-aid)
„
„
„
© Peter Schmidleitner
Pre departure verification of FDE:
Necessary for oceanic/remote operation
with GPS as „sole means of navigation“
G1000: combined with RAIM prediction
© Peter Schmidleitner
FDE
RAIM – the AUGUR tool
http://augur.ecacnav.com/
Excluded
satellite
© Peter Schmidleitner
© Peter Schmidleitner
What is ARINC ?
„
„
ARINC
„
„
„
© Peter Schmidleitner
ARINC = Aeronautical Radio, Inc.
Principal stockholders: US scheduled airlines
Other stockholders: other air transport
companies, aircraft manufacturers, foreign flag
carriers
ARINC sponsors the Airline Electronic
Engineering Committee (AEEC)
AEEC formulates standards for electronic
equipment and systems for airlines
© Peter Schmidleitner
8
ARINC 424
Sample ARIC 424 Data Field
“ARINC 424” specifies the format
of navigation databases
„
„
„
„
„
© Peter Schmidleitner
© Peter Schmidleitner
ARINC 424
ARINC 424
ARINC Specification 424 first
published 21 May 75
Specification amended regularly
Current edition: 424-18
Information up to ARINC 424-3
only included point-to-point-topoint navigation
© Peter Schmidleitner
Conventional procedures
„
„
„
„
„
„
„
ARINC 424-3, published 4 Nov 82,
introduced concept of “path and
terminator” or “leg types”
Concept permits coding of terminal area
procedures, SIDs, STARs and
approaches
Concept established “rules” of coding
Currently there are 23 different “leg
types”
© Peter Schmidleitner
Some of the „Path / Terminators“
Path terminator concept developed to
code existing conventional instrument
procedures
However, not all conventional
procedures are easily coded
“conditional” procedures, easy for pilot
to interpret, are difficult for computer to
describe
© Peter Schmidleitner
© Peter Schmidleitner
9
Operational assumptions
Some of the „Path / Terminators“
Certain path terminator assumptions are
made to accommodate aircraft
performance:
„
„
„
„
speed - 210 K ground speed used to compute
distance based upon 3.5 NM per min
Max 25 degree bank angle used to compute
turn radius
Climb rate of 500 feet per NM used in
computations
Intercept angles - not specified, 30 degrees
for intercept of localizer based and 30 - 45
degrees for all others
© Peter Schmidleitner
© Peter Schmidleitner
Operational considerations
„
„
„
FMS-equipped aircraft fly tracks instead
of procedural headings, provided heading
not required for ATC separation
Stepdown fixes between the FAF and
MAP are not included in navigation
databases
Lead radials are for non-RNAV equipped
aircraft and are not intended to restrict
the use of turn anticipation by the FMS
Operational considerations
„
ICAO: “FMS/RNAV…may be
used…provided:
„
„
„
But this is not permitted according
European regulations!
„
© Peter Schmidleitner
LOAN RW 28
© Peter Schmidleitner
procedure is monitored using basic display
normally associated with that procedure;
and
tolerances for flight using raw data on the
basic display are complied with.”
Only “official” Overlay Procedures may be
flown with RNAV
© Peter Schmidleitner
LOAN RW 28
© Peter Schmidleitner
10
3 operational levels
The right tool at the right time
„
I use conventional aids
„
„
I fly the Database
„
„
A sound decision
Managed mode
Autopilot
FMS Flight plan
Database Proc.
Tactical mode
Selected mode
Autopilot
HDG select
Vert. Speed
Manual mode
Manual mode
Manual flight
You might run into troubles, man!
I know the background and the
limitations, and I will use the right tool at
the right time
„
Strategic mode
You are right! Clever like a pilot!
© Peter Schmidleitner
© Peter Schmidleitner
Types of „Database Procedures“
„
Procedures
„
„
Genuine RNAV (e.g. GPS) procedures,
using published waypoints
„official“ overlay procedures (using
published waypoints)
„unofficial“ overlay procedures
(conventional produres converted into
„database language“)
© Peter Schmidleitner
© Peter Schmidleitner
Genuine RNAV Procedures
„
New criteria introduced into PANS-OPS
to cater to the needs of the modern
aircraft navigation databases
„
„
„
„
„
VOR/DME RNAV (Chap 31)
DME/DME RNAV (Chap 32)
GNSS “basic receiver” criteria (Chap 33)
RNP (Chap 35)
BARO-VNAV (Chap 34)
© Peter Schmidleitner
What is this ?
D359P
Garmin 1000
display
D348O
D348N
D348L
© Peter Schmidleitner
11
ARINC Coding
Distance Coding
Bearing and Distance Waypoints
Identifiers should be developed by the application of the following
rules:
1. The first character of the fix identifier should be “D”.
2. Characters two through four should signify the VHF
NAVAID radial on which the waypoint lies.
3. The last character should be the DME arc radius defining
the position of the waypoint radial. This radius should be
expressed as the equivalent letter of the alphabet, i.e. A =
nm, G = 7nm, O = 15NM, etc.
© Peter Schmidleitner
© Peter Schmidleitner
What is this ?
14 NM
D348N
12 NM
D348L
Approach Chart
D359P
16 NM
D348O
15 NM
D359P
D348O
D348N
D348L
© Peter Schmidleitner
© Peter Schmidleitner
What is this ? # 2
Terminal waypoints
Single Approach Procedure for a runway:
RWY 17C
Final APCH Course Fix
C D 17C
Final APCH Fix
F D 17C
Missed APCH Pt Fix
M D 17C
VOR/DME APCH
CF Final Approach Course Fix
FF Final Approach Fix
MA Missed Approach Point Fix
OM Outer Marker Fix
AF
IF
SD
RC
RW
MM
IM
BM
TD
Initial Approach Fix
Intermediate Approach Fix
Step-Down Fix (or Sx if multiple)
Runway Centerline Fix
Runway Fix
Middle Marker Fix
Inner Marker Fix
Backcourse Marker Fix
Touchdown Fix inboard of runway threshold
Multiple Approach Procedures for a runway:
In case of single procedure:
Fx, Ax, Ix, Cx, Mx, Sx, Rx, Tx where x is the “Route Type”
CF, FF, MA
© Peter Schmidleitner
© Peter Schmidleitner
12
Genuine RNAV APCH
Route types in approach route records
A
B
C
D
E
F
G
H
I
J
K
L
M
N
P
Q
R
S
T
U
V
W
X
Y
Z
Approach Transition
LLZ Backcourse Approach
LORAN Approach
VOR/DME Approach
VOR Circle-To-Land Approach
FMS Approach
IGS (Instrument Guidance System) Approach
Helicopter Approach
ILS Approach
LLZ only Circle-To-Land Approach
LLZ Backcourse Circle-To-Land Approach
Localizer only Approach
MLS Approach
NDB Approach
GPS Approach
NDB/DME Approach
RNAV Approach
VOR Approach with DME Facility
TACAN Approach
NDB Circle-To-Land Approach
VOR Approach (Non-DME Facility)
MLS Type A Approach
LDA (Localizer Directional Aid) Approach
MLS Type B and C Approach
SDF (Simplified Directional Facility) Approach
© Peter Schmidleitner
© Peter Schmidleitner
„Official“ overlay APCH
Conventional Approach
© Peter Schmidleitner
© Peter Schmidleitner
G1000 Limitations
„
„
Limitations
„
„
„
© Peter Schmidleitner
IFR only with valid database, or each
WPT has to be verified
Instrument approaches only in approach
mode and RAIM must be available at FAF
VOR/ILS approaches: VOR/ILS data have
to be on the CDI display
RNAV (GPS) approaches must utilize GPS
sensor
GPS guidance approved only for „GPS
overlay“-approaches
© Peter Schmidleitner
13
G1000 Limitations
„
„
„
Alternate APT: APCH other than GPS
must be available
VNAV: advisory only; Pilot‘s altimeter is
primary reference
Compulsory settings
„
„
„
„
„
DIS, SPD
ALT, VS
MAP DATUM
POSITION
Jeppesen Data Base
Limitations
nm kt
ft fpm
WGS84
deg – min
ILS CDI capture mode: MANUAL, when
coducting AP coupled approach
© Peter Schmidleitner
© Peter Schmidleitner
Jeppesen Limitations
„
„
„
„Uncodeable“ procedures are not
included in the Jeppesen Master
Database.
Stepdown fixes between the FAF and
MAP are not included in navigation
database.
Regardless of what is shown in the
electronic chart, all legs of the procedure
on the paper chart have to be flown as
charted.
© Peter Schmidleitner
Jeppesen Limitations
„
„
You may not be authorized to fly all
procedures in your database. If you don‘t
have a paper chart for it, you are not
authorized to fly it.
Some categories of controlled airspace
are not in your database – Class A, E and
F is not included.
© Peter Schmidleitner
Jeppesen Limitations
„
„
Not all altitudes are in the database.
Not included are:
„
„
„
„
„
„
„
MDA
DA/DH
MOCA
MRA
MSA
MCA
MAA
MSA / ESA
© Peter Schmidleitner
© Peter Schmidleitner
14
MSA
„
„
MSA
Uses Grid Minimum Off-route Altitudes
(Grid MORAs) to determine a safe
altitude within ten miles of your present
position.
Grid MORAs are one degree latitude by
one degree longitude in size and clear all
reference points within the grid by
„
„
1600
49
1700
40
4800
1000 feet in areas where the highest
reference point is 5000 feet MSL or lower.
2000 feet in areas where the highest
reference point is above 5000 feet.
98
56
4700
© Peter Schmidleitner
© Peter Schmidleitner
MSA
MSA
1600
49
1700
1600
40
49
4800
1700
40
LOAN
98
LOGK
4800
LOAV
56
98
5600
5600
56
9800
4700
4700
© Peter Schmidleitner
© Peter Schmidleitner
MSA
1600
49
ESA
1700
„
40
LOAU
4900
8 NM
4800
98
56
„
The recommended minimum altitude
within ten miles, left or right, of your
desired course on an active flight plan or
direct-to.
Like with MSA the
„1000/5000/2000 formula“
is used.
4700
© Peter Schmidleitner
© Peter Schmidleitner
15
ESA
ESA
© Peter Schmidleitner
© Peter Schmidleitner
Practical Hints
„
Practical Hints
„
„
„
© Peter Schmidleitner
© Peter Schmidleitner
ILS frequency
Loading an ILS Approach:
„
Direct-To „Nearest“ from PFD
„
„
„
„
„
© Peter Schmidleitner
Recommended sequence:
„
If you navigate on GPS:
ILS frequency is put into the
„Active“-field!
If you navigate on VHF-NAV:
„ ILS frequency is put into the
„Standby“-field
You have to toggle it manually to „active“
Softkeys
Pay attention to the softkeys !
If there is no softkey for your desired action:
Use the menu
first select frequency
click back to airport
and only then select „Direct-To“
Why?
„
With the „Direct-To“ the „Nearest Aiports“list disappears (and with it the frequency)!
© Peter Schmidleitner
16
Loading a SID
Standard
Instrument
Departures
© Peter Schmidleitner
© Peter Schmidleitner
First leg of SID
This is a CF leg !
© Peter Schmidleitner
© Peter Schmidleitner
Watch your first leg !
Watch your first leg !
Depending on your position, your
active leg might „jump“ down in the
flight plan
„ You will have to activate your first
leg!
„
© Peter Schmidleitner
© Peter Schmidleitner
17