Section 2. Special Operations
10-2-1. Offshore Helicopter Operations
The offshore environment offers unique applications and challenges for
helicopter pilots. The mission demands, the nature of oil and gas
exploration and production facilities, and the flight environment
(weather, terrain, obstacles, traffic), demand special practices,
techniques and procedures not found in other flight operations. Several
industry organizations have risen to the task of reducing risks in
offshore operations, including the Helicopter Safety Advisory
Conference (HSAC) (http://www.hsac.org), and the Offshore
Committee of the Helicopter Association International (HAI)
(http://www.rotor.com). The following recommended practices for
offshore helicopter operations are based on guidance developed by
HSAC for use in the Gulf of Mexico, and provided here with their
permission. While not regulatory, these recommended practices
provide aviation and oil and gas industry operators with useful
information in developing procedures to avoid certain hazards of
offshore helicopter operations.
NOTELike all aviation practices, these recommended practices are under
constant review. In addition to normal procedures for comments,
suggested changes, or corrections to the AIM (contained in the
Preface), any questions or feedback concerning these recommended
procedures may also be directed to the HSAC through the feedback
feature of the HSAC web site (http://www.hsac.org).
b. Passenger Management on and about Heliport Facilities
1. Background. Several incidents involving offshore helicopter
passengers have highlighted the potential for incidents and accidents
on and about the heliport area. The following practices will minimize
risks to passengers and others involved in heliport operations.
2. Recommended Practices
(a) Heliport facilities should have a designated and posted passenger
waiting area which is clear of the heliport, heliport access points, and
stairways.
(b) Arriving passengers and cargo should be unloaded and cleared
from the heliport and access route prior to loading departing
passengers and cargo.
(c) Where a flight crew consists of more than one pilot, one
crewmember should supervise the unloading/loading process from
outside the aircraft.
(d) Where practical, a designated facility employee should assist with
loading/unloading, etc.
c. Crane-Helicopter Operational Procedures
1. Background. Historical experience has shown that catastrophic
consequences can occur when industry safe practices for
crane/helicopter operations are not observed. The following
recommended practices are designed to minimize risks during crane
and helicopter operations.
2. Recommended Practices
(a) Personnel awareness
(1) Crane operators and pilots should develop a mutual understanding
and respect of the others' operational limitations and cooperate in the
spirit of safety;
(2) Pilots need to be aware that crane operators sometimes cannot
release the load to cradle the crane boom, such as when attached to
wire line lubricators or supporting diving bells; and
(3) Crane operators need to be aware that helicopters require warm up
before takeoff, a two-minute cool down before shutdown, and cannot
circle for extended lengths of time because of fuel consumption.
(b) It is recommended that when helicopters are approaching,
maneuvering, taking off, or running on the heliport, cranes be
shutdown and the operator leave the cab. Cranes not in use shall have
their booms cradled, if feasible. If in use, the crane's boom(s) are to be
pointed away from the heliport and the crane shutdown for helicopter
operations.
(c) Pilots will not approach, land on, takeoff, or have rotor blades
turning on heliports of structures not complying with the above
practice.
(d) It is recommended that cranes on offshore platforms, rigs, vessels,
or any other facility, which could interfere with helicopter operations
(including approach/departure paths):
(1) Be equipped with a red rotating beacon or red high intensity strobe
light connected to the system powering the crane, indicating the crane
is under power;
(2) Be designed to allow the operator a maximum view of the helideck
area and should be equipped with wide-angle mirrors to eliminate blind
spots; and
(3) Have their boom tips, headache balls, and hooks painted with high
visibility international orange.
d. Helicopter/Tanker Operations
1. Background. The interface of helicopters and tankers during
shipboard helicopter operations is complex and may be hazardous
unless appropriate procedures are coordinated among all parties. The
following recommended practices are designed to minimize risks
during helicopter/tanker operations:
2. Recommended Practices
(a) Management, flight operations personnel, and pilots should be
familiar with and apply the operating safety standards set forth in
“Guide to Helicopter/Ship Operations”, International Chamber of
Shipping, Third Edition, 5-89 (as amended), establishing operational
guidelines/standards and safe practices sufficient to safeguard
helicopter/tanker operations.
(b) Appropriate plans, approvals, and communications must be
accomplished prior to reaching the vessel, allowing tanker crews
sufficient time to perform required safety preparations and position
crew members to receive or dispatch a helicopter safely.
(c) Appropriate approvals and direct communications with the bridge of
the tanker must be maintained throughout all helicopter/tanker
operations.
(d) Helicopter/tanker operations, including landings/departures, shall
not be conducted until the helicopter pilot-in-command has received
and acknowledged permission from the bridge of the tanker.
(e) Helicopter/tanker operations shall not be conducted during
product/cargo transfer.
(f) Generally, permission will not be granted to land on tankers during
mooring operations or while maneuvering alongside another tanker.
e. Helideck/Heliport Operational Hazard Warning(s) Procedures
1. Background
(a) A number of operational hazards can develop on or near offshore
helidecks or onshore heliports that can be minimized through
procedures for proper notification or visual warning to pilots. Examples
of hazards include but are not limited to:
(1) Perforating operations: subparagraph f.
(2) H2S gas presence: subparagraph g.
(3) Gas venting: subparagraph h; or,
(4) Closed helidecks or heliports: sub-paragraph i (unspecified cause).
(b) These and other operational hazards are currently minimized
through timely dissemination of a written Notice to Airmen (NOTAM)
for pilots by helicopter companies and operators. A NOTAM provides a
written description of the hazard, time and duration of occurrence, and
other pertinent information. ANY POTENTIAL HAZARD should be
communicated to helicopter operators or company aviation
departments as early as possible to allow the NOTAM to be activated.
(c) To supplement the existing NOTAM procedure and further assist in
reducing these hazards, a standardized visual signal(s) on the
helideck/heliport will provide a positive indication to an approaching
helicopter of the status of the landing area. Recommended Practice(s)
have been developed to reinforce the NOTAM procedures and
standardize visual signals.
f. Drilling Rig Perforating Operations: Helideck/Heliport
Operational Hazard Warning(s)/Procedure(s)
1. Background. A critical step in the oil well completion process is
perforation, which involves the use of explosive charges in the drill pipe
to open the pipe to oil or gas deposits. Explosive charges used in
conjunction with perforation operations offshore can potentially be
prematurely detonated by radio transmissions, including those from
helicopters. The following practices are recommended.
2. Recommended Practices
(a) Personnel Conducting Perforating Operations. Whenever
perforating operations are scheduled and operators are concerned that
radio transmissions from helicopters in the vicinity may jeopardize the
operation, personnel conducting perforating operations should take the
following precautionary measures:
(1) Notify company aviation departments, helicopter operators or
bases, and nearby manned platforms of the pending perforation
operation so the Notice to Airmen (NOTAM) system can be activated
for the perforation operation and the temporary helideck closure.
(2) Close the deck and make the radio warning clearly visible to
passing pilots, install a temporary marking (described in
subparagraph 10-2-1i1(b)) with the words “NO RADIO” stenciled in red
on the legs of the diagonals. The letters should be 24 inches high and
12 inches wide.
(See FIG 10-2-1.)
(3) The marker should be installed during the time that charges may be
affected by radio transmissions.
(b) Pilots
(1) Pilots when operating within 1,000 feet of a known perforation
operation or observing the white X with red “NO RADIO” warning
indicating perforation operations are underway will avoid radio
transmissions from or near the helideck (within 1,000 feet) and will not
land on the deck if the X is present. In addition to communications
radios, radio transmissions are also emitted by aircraft radar,
transponders, radar altimeters, and DME equipment, and ELTs.
(2) Whenever possible, make radio calls to the platform being
approached or to the Flight Following Communications Center at least
one mile out on approach. Ensure all communications are complete
outside the 1,000 foot hazard distance. If no response is received, or if
the platform is not radio equipped, further radio transmissions should
not be made until visual contact with the deck indicates it is open for
operation (no white “X”).
g. Hydrogen Sulfide Gas Helideck/Heliport Operational Hazard
Warning(s)/Procedures
1. Background. Hydrogen sulfide (H2S) gas: Hydrogen sulfide gas in
higher concentrations (300-500 ppm) can cause loss of consciousness
within a few seconds and presents a hazard to pilots on/near offshore
helidecks. When operating in offshore areas that have been identified
to have concentrations of hydrogen sulfide gas, the following practices
are recommended.
2. Recommended Practices
(a) Pilots
(1) Ensure approved protective air packs are available for emergency
use by the crew on the helicopter.
(2) If shutdown on a helideck, request the supervisor in charge provide
a briefing on location of protective equipment and safety procedures.
(3) If while flying near a helideck and the visual red beacon alarm is
observed or an unusually strong odor of “rotten eggs” is detected,
immediately don the protective air pack, exit to an area upwind, and
notify the suspected source field of the hazard.
FIG 10-2-1
Closed Helideck Marking - No Radio
(b) Oil Field Supervisors
(1) If presence of hydrogen sulfide is detected, a red rotating beacon or
red high intensity strobe light adjacent to the primary helideck stairwell
or wind indicator on the structure should be turned on to provide visual
warning of hazard. If the beacon is to be located near the stairwell, the
State of Louisiana “Offshore Heliport Design Guide” and FAA Advisory
Circular AC 150/5390-2A, “Heliport Design Guide,” should be reviewed
to ensure proper clearance on the helideck.
(2) Notify nearby helicopter operators and bases of the hazard and
advise when hazard is cleared.
(3) Provide a safety briefing to include location of protective equipment
to all arriving personnel.
(4) Wind socks or indicator should be clearly visible to provide upwind
indication for the pilot.
h. Gas Venting Helideck/Heliport Operational Hazard
Warning(s)/Procedures - Operations Near Gas Vent Booms
1. Background. Ignited flare booms can release a large volume of
natural gas and create a hot fire and intense heat with little time for the
pilot to react. Likewise, unignited gas vents can release reasonably
large volumes of methane gas under certain conditions. Thus,
operations conducted very near unignited gas vents require
precautions to prevent inadvertent ingestion of combustible gases by
the helicopter engine(s). The following practices are recommended.
2. Pilots
(a) Gas will drift upwards and downwind of the vent. Plan the approach
and takeoff to observe and avoid the area downwind of the vent,
remaining as far away as practicable from the open end of the vent
boom.
(b) Do not attempt to start or land on an offshore helideck when the
deck is downwind of a gas vent unless properly trained personnel
verify conditions are safe.
3. Oil Field Supervisors
(a) During venting of large amounts of unignited raw gas, a red rotating
beacon or red high intensity strobe light adjacent to the primary
helideck stairwell or wind indicator should be turned on to provide
visible warning of hazard. If the beacon is to be located near the
stairwell, the State of Louisiana “Offshore Heliport Design Guide” and
FAA Advisory Circular AC 150/5390-2A, Heliport Design Guide, should
be reviewed to ensure proper clearance from the helideck.
(b) Notify nearby helicopter operators and bases of the hazard for
planned operations.
(c) Wind socks or indicator should be clearly visible to provide upward
indication for the pilot.
i. Helideck/Heliport Operational Warning(s)/Procedure(s) - Closed
Helidecks or Heliports
1. Background. A white “X” marked diagonally from corner to corner
across a helideck or heliport touchdown area is the universally
accepted visual indicator that the landing area is closed for safety of
other reasons and that helicopter operations are not permitted. The
following practices are recommended.
(a) Permanent Closing. If a helideck or heliport is to be permanently
closed, X diagonals of the same size and location as indicated above
should be used, but the markings should be painted on the landing
area.
NOTEWhite Decks: If a helideck is painted white, then international orange or
yellow markings can be used for the temporary or permanent
diagonals.
(b) Temporary Closing. A temporary marker can be used for hazards
of an interim nature. This marker could be made from vinyl or other
durable material in the shape of a diagonal “X.” The marker should be
white with legs at least 20 feet long and 3 feet in width. This marker is
designed to be quickly secured and removed from the deck using
grommets and rope ties. The duration, time, location, and nature of
these temporary closings should be provided to and coordinated with
company aviation departments, nearby helicopter bases, and
helicopter operators supporting the area. These markers MUST be
removed when the hazard no longer exists.
(See FIG 10-2-2.)
FIG 10-2-2
Closed Helideck Marking
j. Offshore (VFR) Operating Altitudes for Helicopters
1. Background. Mid-air collisions constitute a significant percentage of
total fatal offshore helicopter accidents. A method of reducing this risk
is the use of coordinated VFR cruising altitudes. To enhance safety
through standardized vertical separation of helicopters when flying in
the offshore environment, it is recommended that helicopter operators
flying in a particular area establish a cooperatively developed Standard
Operating Procedure (SOP) for VFR operating altitudes. An example of
such an SOP is contained in this example.
2. Recommended Practice Example
(a) Field Operations. Without compromising minimum safe operating
altitudes, helicopters working within an offshore field “constituting a
cluster” should use altitudes not to exceed 500 feet.
(b) En Route Operations
(1) Helicopters operating below 750' AGL should avoid transitioning
through offshore fields.
(2) Helicopters en route to and from offshore locations, below 3,000
feet, weather permitting, should use en route altitudes as outlined in
TBL 10-2-1.
TBL 10-2-1
Magnetic Heading Altitude
0° to 179°
750'
1750'
2750'
180° 359°
1250'
2250'
(c) Area Agreements. See HSAC Area Agreement Maps for operating
procedures for onshore high density traffic locations.
NOTEPilots of helicopters operating VFR above 3,000 feet above the surface
should refer to the current Federal Aviation Regulations (14 CFR Part
91), and paragraph 3-1-4, Basic VFR Weather Minimums, of the AIM.
(d) Landing Lights. Aircraft landing lights should be on to enhance
aircraft identification:
(1) During takeoff and landings;
(2) In congested helicopter or fixed wing traffic areas;
(3) During reduced visibility; or,
(4) Anytime safety could be enhanced.
k. Offshore Helidecks/Landing Communications
1. Background. To enhance safety, and provide appropriate time to
prepare for helicopter operations, the following is recommended when
anticipating a landing on an offshore helideck.
2. Recommended Practices
(a) Before landing on an offshore helideck, pilots are encouraged to
establish communications with the company owning or operating the
helideck if frequencies exist for that purpose.
(b) When impracticable, or if frequencies do not exist, pilots or
operations personnel should attempt to contact the company owning or
operating the helideck by telephone. Contact should be made before
the pilot departs home base/point of departure to advise of intentions
and obtain landing permission if necessary.
NOTEIt is recommended that communications be established a minimum of
10 minutes prior to planned arrival time. This practice may be a
requirement of some offshore owner/operators.
NOTE1. See subparagraph 10-2-1d for Tanker Operations.
2. Private use Heliport. Offshore heliports are privately owned/operated
facilities and their use is limited to persons having prior authorization to
utilize the facility.
l. Two (2) Helicopter Operations on Offshore Helidecks
1. Background. Standardized procedures can enhance the safety of
operating a second helicopter on an offshore helideck, enabling pilots
to determine/maintain minimum operational parameters. Orientation of
the parked helicopter on the helideck, wind and other factors may
prohibit multi-helicopter operations. More conservative Rotor Diameter
(RD) clearances may be required under differing condition, i.e.,
temperature, wet deck, wind (velocity/direction/gusts), obstacles,
approach/departure angles, etc. Operations are at the pilot's discretion.
2. Recommended Practice. Helideck size, structural weight capability,
and type of main rotor on the parked and operating helicopter will aid in
determining accessibility by a second helicopter. Pilots should
determine that multi-helicopter deck operations are permitted by the
helideck owner/operator.
3. Recommended Criteria
(a) Minimum one-third rotor diameter clearance (1/3 RD). The
landing helicopter maintains a minimum 1/3 RD clearance between the
tips of its turning rotor and the closest part of a parked and secured
helicopter (rotors stopped and tied down).
(b) Three foot parking distance from deck edge (3'). Helicopters
operating on an offshore helideck land or park the helicopter with a
skid/wheel assembly no closer than 3 feet from helideck edge.
(c) Tiedowns. Main rotors on all helicopters that are shut down be
properly secured (tied down) to prevent the rotor blades from turning.
(d) Medium (transport) and larger helicopters should not land on any
offshore helideck where a light helicopter is parked unless the light
helicopter is property secured to the helideck and has main rotor tied
down.
(e) Helideck owners/operators should ensure that the helideck has a
serviceable anti-skid surface.
4. Weight and limitations markings on helideck. The helideck
weight limitations should be displayed by markings visible to the pilot
(see State of Louisiana “Offshore Heliport Design Guide” and FAA
Advisory Circular AC 150/5390-2A, Heliport Design Guide).
NOTESome offshore helideck owners/operators have restrictions on the
number of helicopters allowed on a helideck. When helideck size
permits, multiple (more than two) helicopter operations are permitted
by some operators.
m. Helicopter Rapid Refueling Procedures (HRR)
1. Background. Helicopter Rapid Refueling (HRR), engine(s)/rotors
operating, can be conducted safely when utilizing trained personnel
and observing safe practices. This recommended practice provides
minimum guidance for HRR as outlined in National Fire Protection
Association (NFPA) and industry practices. For detailed guidance,
please refer to National Fire Protection Association (NFPA) Document
407, “Standard for Aircraft Fuel Servicing,” 1990 edition, including 1993
HRR Amendment.
NOTECertain operators prohibit HRR, or “hot refueling,” or may have specific
procedures for certain aircraft or refueling locations. See the General
Operations Manual and/or Operations Specifications to determine the
applicable procedures or limitations.
2. Recommended Practices
(a) Only turbine-engine helicopters fueled with JET A or JET A-1 with
fueling ports located below any engine exhausts may be fueled while
an onboard engine(s) is (are) operating.
(b) Helicopter fueling while an onboard engine(s) is (are) operating
should only be conducted under the following conditions:
(1) A properly certificated and current pilot is at the controls and a
trained refueler attending the fuel nozzle during the entire fuel servicing
process. The pilot monitors the fuel quantity and signals the refueler
when quantity is reached.
(2) No electrical storms (thunderstorms) are present within 10 nautical
miles. Lightning can travel great distances beyond the actual
thunderstorm.
(3) Passengers disembark the helicopter and move to a safe location
prior to HRR operations. When the pilot-in-command deems it
necessary for passenger safety that they remain onboard, passengers
should be briefed on the evacuation route to follow to clear the area.
(4) Passengers not board or disembark during HRR operations nor
should cargo be loaded or unloaded.
(5) Only designated personnel, trained in HRR operations should
conduct HRR written authorization to include safe handling of the fuel
and equipment. (See your Company Operations/Safety Manual for
detailed instructions.)
(6) All doors, windows, and access points allowing entry to the interior
of the helicopter that are adjacent to or in the immediate vicinity of the
fuel inlet ports kept closed during HRR operations.
(7) Pilots insure that appropriate electrical/electronic equipment is
placed in standby-off position, to preclude the possibility of electrical
discharge or other fire hazard, such as [i.e., weather radar is on
standby and no radio transmissions are made (keying of the
microphone/transmitter)]. Remember, in addition to communications
radios, radio transmissions are also emitted by aircraft radar,
transponders, radar altimeters, DME equipment, and ELTs.
(8) Smoking be prohibited in and around the helicopter during all HRR
operations.
The HRR procedures are critical and present associated hazards
requiring attention to detail regarding quality control, weather
conditions, static electricity, bonding, and spill/fires potential.
Any activity associated with rotors turning (i.e.; refueling
embarking/disembarking, loading/unloading baggage/freight; etc.)
personnel should only approach the aircraft when authorized to do so.
Approach should be made via safe approach path/walkway or “arc”remain clear of all rotors.
NOTE1. Marine vessels, barges etc.: Vessel motion presents additional
potential hazards to helicopter operations (blade flex, aircraft
movement).
2. See National Fire Protection Association (NFPA) Document 407,
“Standard for Aircraft Fuel Servicing” for specifics regarding non-HRR
(routine refueling operations).
10-2-2. Helicopter Night VFR Operations
a. Effect of Lighting on Seeing Conditions in Night VFR Helicopter
Operations
NOTEThis guidance was developed to support safe night VFR helicopter
emergency medical services (HEMS) operations. The principles of
lighting and seeing conditions are useful in any night VFR operation.
While ceiling and visibility significantly affect safety in night VFR
operations, lighting conditions also have a profound effect on safety.
Even in conditions in which visibility and ceiling are determined to be
visual meteorological conditions, the ability to discern unlighted or low
contrast objects and terrain at night may be compromised. The ability
to discern these objects and terrain is the seeing condition, and is
related to the amount of natural and man made lighting available, and
the contrast, reflectivity, and texture of surface terrain and obstruction
features. In order to conduct operations safely, seeing conditions must
be accounted for in the planning and execution of night VFR
operations.
Night VFR seeing conditions can be described by identifying “high
lighting conditions” and “low lighting conditions.”
1. High lighting conditions exist when one of two sets of conditions are
present:
(a) The sky cover is less than broken (less than 5/8 cloud cover), the
time is between the local Moon rise and Moon set, and the lunar disk is
at least 50% illuminated; or
(b) The aircraft is operated over surface lighting which, at least,
provides for the lighting of prominent obstacles, the identification of
terrain features (shorelines, valleys, hills, mountains, slopes) and a
horizontal reference by which the pilot may control the helicopter. For
example, this surface lighting may be the result of:
(1) Extensive cultural lighting (man-made, such as a built-up area of a
city),
(2) Significant reflected cultural lighting (such as the illumination
caused by the reflection of a major metropolitan area's lighting
reflecting off a cloud ceiling), or
(3) Limited cultural lighting combined with a high level of natural
reflectivity of celestial illumination, such as that provided by a surface
covered by snow or a desert surface.
2. Low lighting conditions are those that do not meet the high lighting
conditions requirements.
3. Some areas may be considered a high lighting environment only in
specific circumstances. For example, some surfaces, such as a forest
with limited cultural lighting, normally have little reflectivity, requiring
dependence on significant moonlight to achieve a high lighting
condition. However, when that same forest is covered with snow, its
reflectivity may support a high lighting condition based only on
starlight. Similarly, a desolate area, with little cultural lighting, such as a
desert, may have such inherent natural reflectivity that it may be
considered a high lighting conditions area regardless of season,
provided the cloud cover does not prevent starlight from being
reflected from the surface. Other surfaces, such as areas of open
water, may never have enough reflectivity or cultural lighting to ever be
characterized as a high lighting area.
4. Through the accumulation of night flying experience in a particular
area, the operator will develop the ability to determine, prior to
departure, which areas can be considered supporting high or low
lighting conditions. Without that operational experience, low lighting
considerations should be applied by operators for both pre-flight
planning and operations until high lighting conditions are observed or
determined to be regularly available.
b. Astronomical Definitions and Background Information for Night
Operations
1. Definitions
(a) Horizon. Wherever one is located on or near the Earth's surface,
the Earth is perceived as essentially flat and, therefore, as a plane. If
there are no visual obstructions, the apparent intersection of the sky
with the Earth's (plane) surface is the horizon, which appears as a
circle centered at the observer. For rise/set computations, the
observer's eye is considered to be on the surface of the Earth, so that
the horizon is geometrically exactly 90 degrees from the local vertical
direction.
(b) Rise, Set. During the course of a day the Earth rotates once on its
axis causing the phenomena of rising and setting. All celestial bodies,
the Sun, Moon, stars and planets, seem to appear in the sky at the
horizon to the East of any particular place, then to cross the sky and
again disappear at the horizon to the West. Because the Sun and
Moon appear as circular disks and not as points of light, a definition of
rise or set must be very specific, because not all of either body is seen
to rise or set at once.
(c) Sunrise and sunset refer to the times when the upper edge of the
disk of the Sun is on the horizon, considered unobstructed relative to
the location of interest. Atmospheric conditions are assumed to be
average, and the location is in a level region on the Earth's surface.
(d) Moonrise and moonset times are computed for exactly the same
circumstances as for sunrise and sunset. However, moonrise and
moonset may occur at any time during a 24 hour period and,
consequently, it is often possible for the Moon to be seen during
daylight, and to have moonless nights. It is also possible that a
moonrise or moonset does not occur relative to a specific place on a
given date.
(e) Transit. The transit time of a celestial body refers to the instant that
its center crosses an imaginary line in the sky - the observer's meridian
- running from north to south.
(f) Twilight. Before sunrise and again after sunset there are intervals of
time, known as “twilight,” during which there is natural light provided by
the upper atmosphere, which does receive direct sunlight and reflects
part of it toward the Earth's surface.
(g) Civil twilight is defined to begin in the morning, and to end in the
evening when the center of the Sun is geometrically 6 degrees below
the horizon. This is the limit at which twilight illumination is sufficient,
under good weather conditions, for terrestrial objects to be clearly
distinguished.
2. Title 14 of the Code of Federal Regulations applies these concepts
and definitions in addressing the definition of night (Section 1.1), the
requirement for aircraft lighting (Section 91.209) and pilot recency of
night experience (Section 61.67).
c. Information on Moon Phases and Changes in the Percentage of
the Moon Illuminated
From any location on the Earth, the Moon appears to be a circular disk
which, at any specific time, is illuminated to some degree by direct
sunlight. During each lunar orbit (a lunar month), we see the Moon's
appearance change from not visibly illuminated through partially
illuminated to fully illuminated, then back through partially illuminated to
not illuminated again. There are eight distinct, traditionally recognized
stages, called phases. The phases designate both the degree to which
the Moon is illuminated and the geometric appearance of the
illuminated part. These phases of the Moon, in the sequence of their
occurrence (starting from New Moon), are listed in FIG 10-2-3.
FIG 10-2-3
Phases of the Moon
1. The percent of the Moon's surface illuminated is a more refined,
quantitative description of the Moon's appearance than is the phase.
Considering the Moon as a circular disk, at New Moon the percent
illuminated is 0; at First and Last Quarters it is 50%; and at Full Moon it
is 100%. During the crescent phases the percent illuminated is
between 0 and 50% and during gibbous phases it is between 50% and
100%.
2. For practical purposes, phases of the Moon and the percent of the
Moon illuminated are independent of the location on the Earth from
where the Moon is observed. That is, all the phases occur at the same
time regardless of the observer's position.
3. For more detailed information, refer to the United States Naval
Observatory site referenced below.
d. Access to Astronomical Data for Determination of Moon Rise,
Moon Set, and Percentage of Lunar Disk Illuminated
1. Astronomical data for the determination of Moon rise and set and
Moon phase may be obtained from the United States Naval
Observatory using an interactive query available at:
http://aa.usno.navy.mil/
2. Click on “Data Services,” and then on “Complete Sun and Moon
Data for One Day.”
3. You can obtain the times of sunrise, sunset, moonrise, moonset,
transits of the Sun and Moon, and the beginning and end of civil
twilight, along with information on the Moon's phase by specifying the
date and location in one of the two forms on this web page and clicking
on the “Get data” button at the end of the form. Form “A” is used for
cities or towns in the U.S. or its territories. Form “B” for all other
locations. An example of the data available from this site is shown in
TBL 10-2-2.
4. Additionally, a yearly table may be constructed for a particular
location by using the “Table of Sunrise/Sunset, Moonrise/Moonset, or
Twilight Times for an Entire Year” selection.
TBL 10-2-2
Sample of Astronomical Data Available
from the Naval Observatory
The following information is provided for New Orleans, Orleans
Parish, Louisiana
(longitude W90.1, latitude N30.0)
Tuesday
Central Daylight Time
29 May 2007
SUN
Begin civil twilight
5:34 a.m.
Sunrise
6:01 a.m.
Sun transit
12:58 p.m.
Sunset
7:55 p.m.
End civil twilight
8:22 p.m.
MOON
Moonrise
5:10 p.m. on preceding day
Moonset
4:07 a.m.
Moonrise
6:06 p.m.
Moon transit
11:26 p.m.
Moonset
4:41 a.m. on following day
Phase of the Moon on 29 May: waxing gibbous with 95% of the
Moon's visible disk illuminated.
Full Moon on 31 May 2007 at 8:04 p.m. Central Daylight Time.
10-2-3. Landing Zone Safety
a. This information is provided for use by helicopter emergency
medical services (HEMS) pilots, program managers, medical
personnel, law enforcement, fire, and rescue personnel to further their
understanding of the safety issues concerning Landing Zones (LZs). It
is recommended that HEMS operators establish working relationships
with the ground responder organizations they may come in contact
with in their flight operations and share this information in order to
establish a common frame of reference for LZ selection, operations,
and safety.
b. The information provided is largely based on the booklet, LZ Preparing the Landing Zone, issued by National Emergency Medical
Services Pilots Association (NEMSPA), and the guidance developed
by the University of Tennessee Medical Center's LIFESTAR program,
and is used with their permission. For additional information, go to
http://www.nemspa.org/.
c. Information concerning the estimation of wind velocity is based on
the Beaufort Scale. See
http://www.spc.noaa.gov/faq/tornado/beaufort.html for more
information.
d. Selecting a Scene LZ
1. If the situation requires the use of a helicopter, first check to see if
there is an area large enough to land a helicopter safely.
FIG 10-2-4
Recommended Minimum Landing Zone Dimensions
2. For the purposes of FIG 10-2-4 the following are provided as
examples of relative helicopter size:
(a) Small Helicopter: Bell 206/407, Eurocopter AS-350/355, BO-105,
BK-117.
(b) Medium Helicopter: Bell UH-1 (Huey) and derivatives (Bell
212/412), Bell 222/230/430 Sikorsky S-76, Eurocopter SA-365.
(c) Large Helicopter: Boeing Chinook, Eurocopter Puma, Sikorsky H60 series (Blackhawk), SK-92.
3. The LZ should be level, firm and free of loose debris that could
possibly blow up into the rotor system.
4. The LZ should be clear of people, vehicles and obstructions such as
trees, poles and wires. Remember that wires are difficult to see from
the air. The LZ must also be free of stumps, brush, post and large
rocks. See FIG 10-2-5.
FIG 10-2-5
Landing Zone Hazards
5. Keep spectators back at least 200 feet. Keep emergency vehicles
100 feet away and have fire equipment (if available) standing by.
Ground personnel should wear eye protection, if available, during
landing and takeoff operations. To avoid loose objects being blown
around in the LZ, hats should be removed; if helmets are worn, chin
straps must be securely fastened.
6. Fire fighters (if available) should wet down the LZ if it is extremely
dusty.
e. Helping the Flightcrew Locate the Scene
1. If the LZ coordinator has access to a GPS unit, the exact latitude
and longitude of the LZ should be relayed to the HEMS pilot. If unable
to contact the pilot directly, relay the information to the HEMS ground
communications specialist for relaying to the pilot, so that they may
locate your scene more efficiently. Recognize that the aircraft may
approach from a direction different than the direct path from the takeoff
point to the scene, as the pilot may have to detour around terrain,
obstructions or weather en route.
2. Especially in daylight hours, mountainous and densely populated
areas can make sighting a scene from the air difficult. Often, the LZ
coordinator on the ground will be asked if she or he can see or hear
the helicopter.
3. Flightcrews use a clock reference method for directing one another's
attention to a certain direction from the aircraft. The nose of the aircraft
is always 12 o'clock, the right side is 3 o'clock, etc. When the LZ
coordinator sees the aircraft, he/she should use this method to assist
the flightcrew by indicating the scene's clock reference position from
the nose of the aircraft. For example, “Accident scene is located at
your 2 o'clock position.” See FIG 10-2-6.
FIG 10-2-6
"Clock" System for Identifying Positions
Relative to the Nose of the Aircraft
4. When the helicopter approaches the scene, it will normally orbit at
least one time as the flight crew observes the wind direction and
obstacles that could interfere with the landing. This is often referred to
as the “high reconnaissance” maneuver.
f. Wind Direction and Touchdown Area
1. Determine from which direction the wind is blowing. Helicopters
normally land and takeoff into the wind.
2. If contact can be established with the pilot, either directly or
indirectly through the HEMS ground communications specialist,
describe the wind in terms of the direction the wind is from and the
speed.
3. Common natural sources of wind direction information are smoke,
dust, vegetation movement, water streaks and waves. Flags,
pennants, streamers can also be used. When describing the direction,
use the compass direction from which the wind is blowing (example:
from the North-West).
4. Wind speed can be measured by small hand-held measurement
devices, or an observer's estimate can be used to provide velocity
information. The wind value should be reported in knots (nautical miles
per hour). If unable to numerically measure wind speed, use TBL 10-23 to estimate velocity. Also, report if the wind conditions are gusty, or if
the wind direction or velocity is variable or has changed recently.
5. If any obstacle(s) exist, insure their description, position and
approximate height are communicated to the pilot on the initial radio
call.
TBL 10-2-3
Table of Common References for Estimating Wind Velocity
Wind
Wind
Appearance of Wind Effects
(Knots) Classification
On the Water
On Land
Less
Calm
Sea surface smooth and Calm, smoke rises
than 1
mirror-like
vertically
1-3
Light Air
Scaly ripples, no foam Smoke drift indicates
crests
wind direction, wind
vanes are still
4-6
Light Breeze Small wavelets, crests Wind felt on face,
glassy, no breaking
leaves rustle, vanes
begin to move
7-10
Gentle Breeze Large wavelets, crests Leaves and small
begin to break,
twigs constantly
scattered whitecaps
moving, light flags
extended
11-16 Moderate
Small waves 1-4 ft.
Dust, leaves, and
Breeze
becoming longer,
loose paper lifted,
numerous whitecaps
small tree branches
move
17-21 Fresh Breeze Moderate waves 4-8 ft. Small trees in leaf
taking longer form,
begin to sway
many whitecaps, some
spray
22-27 Strong Breeze Larger waves 8-13 ft., Larger tree branches
whitecaps common,
moving, whistling in
more spray
wires
28-33 Near Gale
Sea heaps up, waves
Whole trees moving,
13-20 ft., white foam
resistance felt
streaks off breakers
walking against wind
34-40 Gale
Moderately high (13-20 Whole trees in
ft.) waves of greater
motion, resistance
length, edges of crests felt walking against
begin to break into
wind
spindrift, foam blown in
streaks
41-47
48-55
56-63
64+
Strong Gale
High waves (20 ft.), sea
begins to roll, dense
streaks of foam, spray
may reduce visibility
Storm
Very high waves (20-30
ft.) with overhanging
crests, sea white with
densely blown foam,
heavy rolling, lowered
visibility
Violent Storm Exceptionally high (3045 ft.) waves, foam
patches cover sea,
visibility more reduced
Hurricane
Air filled with foam,
waves over 45 ft., sea
completely white with
driving spray, visibility
greatly reduced
Slight structural
damage occurs, slate
blows off roofs
Seldom experienced
on land, trees broken
or uprooted,
"considerable
structural damage"
EXAMPLEWind from the South-East, estimated speed 15 knots. Wind shifted
from North-East about fifteen minutes ago, and is gusty.
g. Night LZs
1. There are several ways to light a night LZ:
(a) Mark the touchdown area with five lights or road flares, one in each
corner and one indicating the direction of the wind. See FIG 10-2-7.
FIG 10-2-7
Recommended Lighting for
Landing Zone Operations at Night
NOTE-
Road flares are an intense source of ignition and may be unsuitable or
dangerous in certain conditions. In any case, they must be closely
managed and firefighting equipment should be present when used.
Other light sources are preferred, if available.
(b) If chemical light sticks may be used, care should be taken to assure
they are adequately secured against being dislodged by the
helicopter's rotor wash.
(c) Another method of marking a LZ uses four emergency vehicles with
their low beam headlights aimed toward the intended landing area.
(d) A third method for marking a LZ uses two vehicles. Have the
vehicles direct their headlight beams into the wind, crossing at the
center of the LZ. (If fire/rescue personnel are available, the reflective
stripes on their bunker gear will assist the pilot greatly.)
2. At night, spotlights, flood lights and hand lights used to define the LZ
are not to be pointed at the helicopter. However, they are helpful when
pointed toward utility poles, trees or other hazards to the landing
aircraft. White lights such as spotlights, flashbulbs and hi-beam
headlights ruin the pilot's night vision and temporarily blind him. Red
lights, however, are very helpful in finding accident locations and do
not affect the pilot's night vision as significantly.
3. As in Day LZ operations, ensure radio contact is accomplished
between ground and air, if possible.
h. Ground Guide
1. When the helicopter is in sight, one person should assist the LZ
Coordinator by guiding the helicopter into a safe landing area. In
selecting an LZ Coordinator, recognize that medical personnel usually
are very busy with the patient at this time. It is recommended that the
LZ Coordinator be someone other than a medical responder, if
possible. Eye protection should be worn. The ground guide should
stand with his/her back to the wind and his/her arms raised over
his/her head (flashlights in each hand for night operations.)
2. The pilot will confirm the LZ sighting by radio. If possible, once the
pilot has identified the LZ, the ground guide should move out of the LZ.
3. As the helicopter turns into the wind and begins a descent, the LZ
coordinator should provide assistance by means of radio contact, or
utilize the “unsafe signal” to wave off the helicopter if the LZ is not safe
(see FIG 10-2-8). The LZ Coordinator should be far enough from the
touchdown area that he/she can still maintain visual contact with the
pilot.
i. Assisting the Crew
1. After the helicopter has landed, do not approach the helicopter. The
crew will approach you.
2. Be prepared to assist the crew by providing security for the
helicopter. If asked to provide security, allow no one but the crew to
approach the aircraft.
3. Once the patient is prepared and ready to load, allow the crew to
open the doors to the helicopter and guide the loading of the patient.
4. When approaching or departing the helicopter, always be aware of
the tail rotor and always follow the directions of the crew. Working
around a running helicopter can be potentially dangerous. The
environment is very noisy and, with exhaust gases and rotor wash,
often windy. In scene operations, the surface may be uneven, soft, or
slippery which can lead to tripping. Be very careful of your footing in
this environment.
5. The tail rotor poses a special threat to working around a running
helicopter. The tail rotor turns many times faster than the main rotor,
and is often invisible even at idle engine power. Avoid walking towards
the tail of a helicopter beyond the end of the cabin, unless specifically
directed by the crew.
NOTEHelicopters typically have doors on the sides of the cabin, but many
use aft mounted “clamshell” type doors for loading and unloading
patients on litters or stretchers. When using these doors, it is important
to avoid moving any further aft than necessary to operate the doors
and load/unload the patient. Again, always comply with the crew's
instructions.
j. General Rules
1. When working around helicopters, always approach and depart from
the front, never from the rear. Approaching from the rear can increase
your risk of being struck by the tail rotor, which, when at operating
engine speed, is nearly invisible.
2. To prevent injury or damage from the main rotor, never raise
anything over your head.
3. If the helicopter landed on a slope, approach and depart from the
down slope side only.
4. When the helicopter is loaded and ready for take off, keep the
departure path free of vehicles and spectators. In an emergency, this
area is needed to execute a landing.
k. Hazardous Chemicals and Gases
1. Responding to accidents involving hazardous materials requires
special handling by fire/rescue units on the ground. Equally important
are the preparations and considerations for helicopter operations in
these areas.
2. Hazardous materials of concern are those which are toxic,
poisonous, flammable, explosive, irritating, or radioactive in nature.
Helicopter ambulance crews normally don't carry protective suits or
breathing apparatuses to protect them from hazardous materials.
3. The helicopter ambulance crew must be told of hazardous materials
on the scene in order to avoid the contamination of the crew.
Patients/victims contaminated by hazardous materials may require
special precautions in packaging before loading on the aircraft for the
medical crew's protection, or may be transported by other means.
4. Hazardous chemicals and gases may be fatal to the unprotected
person if inhaled or absorbed through the skin.
5. Upon initial radio contact, the helicopter crew must be made aware
of any hazardous gases in the area. Never assume that the crew has
already been informed. If the aircraft were to fly through the hazardous
gases, the crew could be poisoned and/or the engines could develop
mechanical problems.
6. Poisonous or irritating gases may cling to a victim's clothing and go
unnoticed until the patient is loaded and the doors of the helicopter are
closed. To avoid possible compromise of the crew, all of these patients
must be decontaminated prior to loading.
l. Hand Signals
1. If unable to make radio contact with the HEMS pilot, use the
following signals:
FIG 10-2-8
Recommended Landing Zone Ground Signals
m. Emergency Situations
1. In the event of a helicopter accident in the vicinity of the LZ, consider
the following:
(a) Emergency Exits:
(1) Doors and emergency exits are typically prominently marked. If
possible, operators should familiarize ground responders with the door
system on their helicopter in preparation for an emergency event.
(2) In the event of an accident during the LZ operation, be cautious of
hazards such as sharp and jagged metal, plastic windows, glass, any
rotating components, such as the rotors, and fire sources, such as the
fuel tank(s) and the engine.
(b) Fire Suppression:
Helicopters used in HEMS operations are usually powered by
turboshaft engines, which use jet fuel. Civil HEMS aircraft typically
carry between 50 and 250 gallons of fuel, depending upon the size of
the helicopter, and planned flight duration, and the fuel remaining after
flying to the scene. Use water to control heat and use foam over fuel to
keep vapors from ignition sources.
10-2-4. Emergency Medical Service (EMS) Multiple Helicopter
Operations
a. Background. EMS helicopter operators often overlap other EMS
operator areas. Standardized procedures can enhance the safety of
operating multiple helicopters to landing zones (LZs) and to hospital
heliports. Communication is the key to successful operations and in
maintaining organization between helicopters, ground units and
communication centers. EMS helicopter operators which operate in the
same areas should establish joint operating procedures and provide
them to related agencies.
b. Recommended Procedures.
1. Landing Zone Operations. The first helicopter to arrive on-scene
should establish communications with the ground unit at least 10 NMs
from the LZ to receive a LZ briefing and to provide ground control the
number of helicopters that can be expected. An attempt should be
made to contact other helicopters on 123.025 to pass on to them
pertinent LZ information and the ground unit's frequency. Subsequent
helicopters arriving on scene should establish communications on
123.025 at least 10 NMs from the LZ. After establishing contact on
123.025, they should contact the ground unit for additional information.
All helicopters should monitor 123.025 at all times.
(a) If the landing zone is not established by the ground unit when the
first helicopter arrives, then the first helicopter should establish altitude
and orbit location requirements for the other arriving helicopters.
Recommended altitude separation between helicopters is 500 feet
(weather and airspace permitting). Helicopters can orbit on cardinal
headings from the scene coordinates. (See FIG 10-2-9.)
(b) Upon landing in the LZ, the first helicopter should update the other
helicopters on the LZ conditions, i.e., space, hazards and terrain.
(c) Before initiating any helicopter movement to leave the LZ, all
operators should attempt to contact other helicopters on 123.025, and
state their position and route of flight intentions for departing the LZ.
2. Hospital Operations. Because many hospitals require landing
permission and have established procedures (frequencies to monitor,
primary and secondary routes for approaches and departures, and
orbiting areas if the heliport is occupied) pilots should always receive a
briefing from the appropriate facility (communication center, flight
following, etc.) before proceeding to the hospital.
(a) In the event of multiple helicopters coming into the hospital heliport,
the helicopter nearest to the heliport should contact other inbound
helicopters on 123.025 and establish intentions. Follow the guidelines
established in the LZ operations.
(b) To facilitate approach times, the pilot-in-command of the helicopter
occupying the hospital heliport should advise any other operators
whether the patient will be off loaded with the rotor blades turning or
stopped, and the approximate time to do so.
(c) Before making any helicopter movement to leave the hospital
heliport, all operators should attempt to contact other helicopters on
123.025 and state their position and route of flight intentions for
departing the heliport.
FIG 10-2-9
EMS Multiple Helicopter LZ/Heliport Operation
NOTEIf the LZ/hospital heliport weather conditions or airspace altitude
restrictions prohibit the recommended vertical separation, 1 NM
separations should be kept between helicopter orbit areas.
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