and Urgency Communications
A pilot who encounters a distress
or urgency condition can obtain assistance
simply by contacting the air traffic facility or other
agency in whose area of responsibility the aircraft is
operating, stating the nature of the difficulty,
pilot's intentions and assistance desired. Distress
and urgency communications procedures are
prescribed by the International Civil Aviation
Organization (ICAO), however, and have decided
advantages over the informal procedure described
Distress and urgency
communications procedures discussed in the following
paragraphs relate to the use of air ground voice
The initial communication, and if
considered necessary, any subsequent transmissions by
an aircraft in distress should begin with the
signal MAYDAY, preferably repeated three times. The
signal PAN-PAN should be used in the same manner for
an urgency condition.
Distress communications have
absolute priority over all other communications, and
the word MAYDAY commands radio silence on the
frequency in use. Urgency communications have
priority over all other communications except
distress, and the word PAN-PAN warns other
stations not to interfere with urgency
Normally, the station addressed will be
the air traffic facility or other agency providing air
traffic services, on the frequency in use at the time.
If the pilot is not communicating and receiving
services, the station to be called will normally be
the air traffic facility or other agency in whose area
of responsibility the aircraft is operating, on the
appropriate assigned frequency. If the station
addressed does not respond, or if time or the
situation dictates, the distress or urgency
message may be broadcast, or a collect call may be
used, addressing "Any Station (Tower)(Radio)(Radar)."
The station addressed should
immediately acknowledge a distress or
urgency message, provide assistance, coordinate
and direct the activities of assisting facilities, and
alert the appropriate search and rescue coordinator if
warranted. Responsibility will be transferred to
another station only if better handling will result.
All other stations, aircraft and
ground, will continue to listen until it is evident
that assistance is being provided. If any station
becomes aware that the station being called either has
not received a distress or urgency
message, or cannot communicate with the aircraft in
difficulty, it will attempt to contact the aircraft
and provide assistance.
Although the frequency in use or other
frequencies assigned by ATC are preferable, the
following emergency frequencies can be used for
distress or urgency communications, if necessary or
1. 121.5 MHz
and 243.0 MHz.
have a range generally limited to line of sight.
121.5 MHz is guarded by direction finding stations
and some military and civil aircraft. 243.0 MHz is
guarded by military aircraft. Both 121.5 MHz and
243.0 MHz are guarded by military towers, most civil
towers, FSS's, and radar facilities. Normally ARTCC
emergency frequency capability does not extend to
radar coverage limits. If an ARTCC does not respond
when called on 121.5 MHz or 243.0 MHz, call the
nearest tower or FSS.
2. 2182 kHz.
The range is generally
less than 300 miles for the average aircraft
installation. It can be used to request assistance
from stations in the maritime service. 2182 kHz is
guarded by major radio stations serving Coast Guard
Rescue Coordination Centers, and Coast Guard units
along the sea coasts of the U.S. and shores of the
Great Lakes. The call "Coast Guard" will alert all
Coast Guard Radio Stations within range. 2182 kHz is
also guarded by most commercial coast stations and
some ships and boats.
Obtaining Emergency Assistance
A pilot in any distress
or urgency condition should immediately
take the following action, not necessarily in the
order listed, to obtain assistance:
Climb, if possible, for improved
communications, and better radar and direction
finding detection. However, it must be understood
that unauthorized climb or descent under IFR
conditions within controlled airspace is prohibited,
except as permitted by 14 CFR Section 91.3(b).
If equipped with a radar beacon
transponder (civil) or IFF/SIF (military):
Continue squawking assigned Mode
A/3 discrete code/VFR code and Mode C altitude
encoding when in radio contact with an air traffic
facility or other agency providing air traffic
services, unless instructed to do otherwise.
If unable to immediately establish
communications with an air traffic
facility/agency, squawk Mode A/3, Code
7700/Emergency and Mode C.
Transmit a distress or
urgency message consisting of as many as
necessary of the following elements, preferably in
the order listed:
If distress, MAYDAY, MAYDAY,
MAY-DAY; if urgency, PAN-PAN, PAN-PAN,
Name of station addressed.
Aircraft identification and type.
Nature of distress or
Pilots intentions and request.
Present position, and heading; or
if lost, last known position, time, and
heading since that position.
Altitude or flight level.
Fuel remaining in minutes.
Number of people on board.
Any other useful information.
Pilot/Controller Glossary Term- Fuel Remaining.
After establishing radio contact,
comply with advice and instructions received.
Cooperate. Do not hesitate to ask questions or clarify
instructions when you do not understand or if you
cannot comply with clearance. Assist the ground
station to control communications on the frequency in
use. Silence interfering radio stations. Do not change
frequency or change to another ground station unless
absolutely necessary. If you do, advise the ground
station of the new frequency and station name prior to
the change, transmitting in the blind if necessary. If
two-way communications cannot be established on the
new frequency, return immediately to the frequency or
station where two-way communications last existed.
When in a distress condition with
bailout, crash landing or ditching imminent, take the
following additional actions to assist search and
Time and circumstances permitting,
transmit as many as necessary of the message
elements in subparagraph a3 above, and any of the
following that you think might be helpful:
Number of persons on board.
Emergency equipment on board.
Actuate your ELT if the installation
For bailout, and for crash landing or
ditching if risk of fire is not a consideration, set
your radio for continuous transmission.
If it becomes necessary to ditch,
make every effort to ditch near a surface vessel. If
time permits, an FAA facility should be able to get
the position of the nearest commercial or Coast
Guard vessel from a Coast Guard Rescue Coordination
After a crash landing, unless you
have good reason to believe that you will not be
located by search aircraft or ground teams, it is
best to remain with your aircraft and prepare means
for signaling search aircraft.
A successful aircraft ditching is
dependent on three primary factors. In order of
importance they are:
1. Sea conditions
2. Type of
3. Skill and
technique of pilot.
The condition of the surface that
is the result of both waves and swells.
(or Chop). The condition of the
surface caused by the local winds.
The condition of the surface
which has been caused by a distance disturbance.
4. Swell Face.
The side of the swell
toward the observer. The backside is the side away
from the observer. These definitions apply
regardless of the direction of swell movement.
5. Primary Swell.
The swell system having
the greatest height from trough to crest.
Swells. Those swell
systems of less height than the primary swell.
The distance the waves have been
driven by a wind blowing in a constant direction,
8. Swell Period.
The time interval between
the passage of two successive crests at the same
spot in the water, measured in seconds.
9. Swell Velocity.
The speed and direction of
the swell with relation to a fixed reference point,
measured in knots. There is little movement of water
in the horizontal direction. Swells move primarily
in a vertical motion, similar to the motion observed
when shaking out a carpet.
Direction. The direction
from which a swell is moving. This direction
is not necessarily the result of the wind present at
the scene. The swell may be moving into or across
the local wind. Swells, once set in motion, tend to
maintain their original direction for as long as
they continue in deep water, regardless of changes
in wind direction.
11. Swell Height.
The height between crest
and trough, measured in feet. The vast majority of
ocean swells are lower than 12 to 15 feet, and
swells over 25 feet are not common at any spot on
the oceans. Successive swells may differ
considerably in height.
In order to select a good heading when
ditching an aircraft, a basic evaluation of the sea is
required. Selection of a good ditching heading may
well minimize damage and could save your life. It can
be extremely dangerous to land into the wind without
regard to sea conditions; the swell system, or
systems, must be taken into consideration. Remember
one axiom- AVOID THE FACE OF A SWELL.
In ditching parallel to the swell, it
makes little difference whether touchdown is on the
top of the crest or in the trough. It is preferable,
however, to land on the top or back side of the
swell, if possible. After determining which heading
(and its reciprocal) will parallel the swell, select
the heading with the most into the wind component.
If only one swell system exists, the
problem is relatively simple-even with a high, fast
system. Unfortunately, most cases involve two or
more swell systems running in different directions.
With more than one system present, the sea presents
a confused appearance. One of the most difficult
situations occurs when two swell systems are at
right angles. For example, if one system is eight
feet high, and the other three feet, plan to land
parallel to the primary system, and on the down
swell of the secondary system. If both systems are
of equal height, a compromise may be
advisable-select an intermediate heading at 45
degrees down swell to both systems. When landing
down a secondary swell, attempt to touch down on the
back side, not on the face of the swell.
If the swell system is formidable, it
is considered advisable, in landplanes, to accept
more crosswind in order to avoid landing directly
into the swell.
The secondary swell system is often
from the same direction as the wind. Here, the
landing may be made parallel to the primary system,
with the wind and secondary system at an angle.
There is a choice to two directions paralleling the
primary system. One direction is downwind and down
the secondary swell, and the other is into the wind
and into the secondary swell, the choice will depend
on the velocity of the wind versus the velocity and
height of the secondary swell.
The simplest method of estimating the
wind direction and velocity is to examine the
windstreaks on the water. These appear as long streaks
up and down wind. Some persons may have difficulty
determining wind direction after seeing the streaks on
the water. Whitecaps fall forward with the wind but
are overrun by the waves thus producing the illusion
that the foam is sliding backward. Knowing this, and
by observing the direction of the streaks, the wind
direction is easily determined. Wind velocity can be
estimated by noting the appearance of the whitecaps,
foam and wind streaks.
The behavior of the aircraft on
making contact with the water will vary within wide
limits according to the state of the sea. If landed
parallel to a single swell system, the behavior of
the aircraft may approximate that to be expected on
a smooth sea. If landed into a heavy swell or into a
confused sea, the deceleration forces may be
extremely great-resulting in breaking up of the
aircraft. Within certain limits, the pilot is able
to minimize these forces by proper sea evaluation
and selection of ditching heading.
When on final approach the pilot
should look ahead and observe the surface of the
sea. There may be shadows and whitecaps-signs of
large seas. Shadows and whitecaps close together
indicate short and rough seas. Touchdown in these
areas is to be avoided. Select and touchdown in any
area (only about 500 feet is needed) where the
shadows and whitecaps are not so numerous.
Touchdown should be at the lowest
speed and rate of descent which permit safe handling
and optimum nose up attitude on impact. Once first
impact has been made, there is often little the
pilot can do to control a landplane.
Once preditching preparations are
completed, the pilot should turn to the ditching
heading and commence let-down. The aircraft should be
flown low over the water, and slowed down until ten
knots or so above stall. At this point, additional
power should be used to overcome the increased drag
caused by the nose up attitude. When a smooth stretch
of water appears ahead, cut power, and touchdown at
the best recommended speed as fully stalled as
possible. By cutting power when approaching a
relatively smooth area, the pilot will prevent
overshooting and will touchdown with less chance of
planing off into a second uncontrolled landing. Most
experienced seaplane pilots prefer to make contact
with the water in a semi-stalled attitude, cutting
power as the tail makes contact. This technique
eliminates the chance of misjudging altitude with a
resultant heavy drop in a fully stalled condition.
Care must be taken not to drop the aircraft from too
high altitude or to balloon due to excessive speed.
The altitude above water depends on the aircraft. Over
glassy smooth water, or at night without sufficient
light, it is very easy, for even the most experienced
pilots to misjudge altitude by 50 feet or more. Under
such conditions, carry enough power to maintain nine
to twelve degrees nose up attitude, and 10 to 20
percent over stalling speed until contact is made with
the water. The proper use of power on the approach is
of great importance. If power is available on one side
only, a little power should be used to flatten the
approach; however, the engine should not be used to
such an extent that the aircraft cannot be turned
against the good engines right down to the stall with
a margin of rudder movement available. When near the
stall, sudden application of excessive unbalanced
power may result in loss of directional control. If
power is available on one side only, a slightly higher
than normal glide approach speed should be used. This
will insure good control and some margin of speed
after leveling off without excessive use of power. The
use of power in ditching is so important that when it
is certain that the coast cannot be reached, the pilot
should, if possible, ditch before fuel is exhausted.
The use of power in a night or instrument ditching is
far more essential than under daylight contact
If no power is available, a greater
than normal approach speed should be used down to
the flare-out. This speed margin will allow the
glide to be broken early and more gradually, thereby
giving the pilot time and distance to feel for the
surface - decreasing the possibility of stalling
high or flying into the water. When landing parallel
to a swell system, little difference is noted
between landing on top of a crest or in the trough.
If the wings of aircraft are trimmed to the surface
of the sea rather than the horizon, there is little
need to worry about a wing hitting a swell crest.
The actual slope of a swell is very gradual. If
forced to land into a swell, touchdown should be
made just after passage of the crest. If contact is
made on the face of the swell, the aircraft may be
swamped or thrown violently into the air, dropping
heavily into the next swell. If control surfaces
remain intact, the pilot should attempt to maintain
the proper nose above the horizon attitude by rapid
and positive use of the controls.
f. After Touchdown.
In most cases drift, caused
by crosswind can be ignored; the forces acting on the
aircraft after touchdown are of such magnitude that
drift will be only a secondary consideration. If the
aircraft is under good control, the "crab" may be
kicked out with rudder just prior to touchdown. This
is more important with high wing aircraft, for they
are laterally unstable on the water in a crosswind and
may roll to the side in ditching.
This information has been extracted from Appendix H of
the "National Search and Rescue Manual."
Special Emergency (Air Piracy)
A special emergency is a condition of
air piracy, or other hostile act by a person(s) aboard
an aircraft, which threatens the safety of the
aircraft or its passengers.
The pilot of an aircraft reporting a
special emergency condition should:
If circumstances permit, apply
distress or urgency radio-telephony
procedures. Include the details of the special
AIM, Distress and Urgency Communications, Paragraph
If circumstances do not permit the
use of prescribed distress or urgency
On the air/ground frequency in use
at the time.
As many as possible of the
following elements spoken distinctly and in the
Name of the station addressed
(time and circumstances permitting).
The identification of the
aircraft and present position.
The nature of the special
emergency condition and pilot intentions
If unable to provide this
information, use code words and/or transponder
TRANSPONDER SEVEN FIVE ZERO ZERO
I am being hijacked/forced to a new
Mode 3/A, Code 7500
Code 7500 will never be assigned by ATC without
prior notification from the pilot that the
aircraft is being subjected to unlawful
interference. The pilot should refuse the
assignment of Code 7500 in any other situation
and inform the controller accordingly. Code 7500
will trigger the special emergency indicator in
all radar ATC facilities.
Air traffic controllers will
acknowledge and confirm receipt of transponder Code
7500 by asking the pilot to verify it. If the aircraft
is not being subjected to unlawful interference, the
pilot should respond to the query by broadcasting in
the clear that the aircraft is not being subjected to
unlawful interference. Upon receipt of this
information, the controller will request the pilot to
verify the code selection depicted in the code
selector windows in the transponder control panel and
change the code to the appropriate setting. If the
pilot replies in the affirmative or does not reply,
the controller will not ask further questions but will
flight follow, respond to pilot requests and notify
If it is possible to do so without
jeopardizing the safety of the flight, the pilot of a
hijacked passenger aircraft, after departing from the
cleared routing over which the aircraft was operating,
will attempt to do one or more of the following
things, insofar as circumstances may permit:
Maintain a true airspeed of no more
than 400 knots, and preferably an altitude of
between 10,000 and 25,000 feet.
Fly a course toward the destination
which the hijacker has announced.
If these procedures result in either
radio contact or air intercept, the pilot will attempt
to comply with any instructions received which may
direct the aircraft to an appropriate landing field.
Should it become necessary to dump
fuel, the pilot should immediately advise ATC. Upon
receipt of information that an aircraft will dump
fuel, ATC will broadcast or cause to be broadcast
immediately and every 3 minutes thereafter the
following on appropriate ATC and FSS radio
Attention all aircraft-fuel dumping in progress
over-(location) at (altitude) by (type aircraft)
Upon receipt of such a broadcast,
pilots of aircraft affected, which are not on IFR
flight plans or special VFR clearances, should clear
the area specified in the advisory. Aircraft on IFR
flight plans or special VFR clearances will be
provided specific separation by ATC. At the
termination of the fuel dumping operation, pilots
should advise ATC. Upon receipt of such information,
ATC will issue, on the appropriate frequencies, the
ATTENTION ALL AIRCRAFT-FUEL DUMPING BY-(type