TM 55-1510-215-10
The wind driven sea, if any, will be recognized by the
anticipated and available power is
appearance of white caps.
insufficient to maintain desired rate of
descent, consideration should be
b. Ditching Under IMC Conditions. Where IMC
given to utilization of approach flaps. It
conditions or night operations preclude visual
is difficult to judge height above a calm
determination of sea conditions, forecast data should be
sea, and use of landing lights at night
utilized, and the ditching must be made on instruments.
make the estimate even more difficult
With no surface reference, the aircraft must be flown into
the water on heading, and in a fixed attitude which
WARNING
combines safe control speed and rate of descent.
Whenever possible, ditching should be made as close as
safety permits to coastlines or in the vicinity of surface
vessels to improve the rescue situation. If radios are still
Do not remove raft from its carrying
operational, attempt to contact coastal stations or surface
case inside the aircraft.
vessels for current wind, sea swell, and altimeter setting.
NOTE
CAUTION
Ditch parallel to and near the crest of
the swell unless there is a strong
crosswind of 20 knots or more. In
strong winds ditch heading should be
Keep life raft away from any damaged
more into the wind and slightly
surfaces which might tear it.
across the swell, planning to
touchdown on the upslope of the
swell near the top (fig. 9-6). Wave
WARNING
motion is indicative of wind direction,
but the swell does not necessarily
move with the wind. Water surface
Do not unstrap from the seat until all
conditions
are
indicative
of
motion stops. The possibility of injury
windspeed, as related below:
and disorientation requires that
evacuation not be attempted until the
aircraft comes to a complete stop.
SURFACE CONDITION
WIND
SPEED KNOTS
c. Ditching Procedure.
Few white crests
10-15
Many white crests
15-25
(1) Ditching procedure with power
Streaks of foam from crests
25-35
Spray blown from tops of
1. Announce intention to ditch and time
waves
35-45
to impact.
NOTE
2. Distress message - Transmit
Full flaps are recommended for power
on ditching.
However, impaired
3. Transponder - Emergency.
directional control caused by engine
loss or aileron damage is another
4. Life vest - Put on and adjust (do not
factor to be considered in determining
inflate).
ditching configuration. At low gross
weights, it is possible to retain an
5. Seat belts/harnesses
-
Secure
optimum ditching airspeed, desired
(passengers in braced position).
rate of descent, and directional control
by using full flaps and power as
6. Gear - UP.
necessary on the operating engine. If
direction
control
problems
am
7. Flaps Down.
9-18
