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The major unanswered question pertaining to this fatal accident is why bailout or ditching was not effected prior to loss of flight control. Answers to this
question are quite complex and would be pure conjecture, but one thing for sure, the subject of ditching and bailout from the p-3 should be expounded upon.
The decision of whether to bailout or ditch
primarily involves aircraft control. When loss of control is considered imminent, bailout must be initiated and executed in a quick, orderly fashion. Wing fire forward of the flaps or aileron, damaged or binding
control surfaces that make slow flight impossible and complete power loss comprise some of the conditions that would influence a pilot's decision to bailout. Wing fires, exclusive of the engine nacelle forward of
the fire wall, constitute the most precarious situation where loss of control is imminent. Rapid bailout in this case is strongly recommended since the execution of a successful ditching is unlikely once the
flap/aileron surfaces are destroyed. The aircraft's position relative to possible surface rescue vessels has an important bearing on the bailout decision. To scatter the crew in an open ocean many miles from a
surface vessel with only a life jacket for survival is questionable and should be resorted to only when ditching cannot be accomplished. The possibility of attaching a compact one-man raft to the parachute harness
should be investigated.
I believe that the P-3 can be safely ditched, contrary to the old wives tale being circulated on the hangar deck. True, the P-3 has not been involved in a successful ditching
to date; however, the accident reports of five collision-with-water type mishaps all conclude that the aircraft were either inadvertently flown into the water or the pilot lost control and subsequently stalled/spun
prior to impact.
My opinions of P-3 ditching capability are based on two factors: my seaplane open-sea experience and the airframe construction/configuration of the Orion. In comparison with other
types, the P-3 closely resembles the C-118 transport, i.e., low-wing monoplane equipped with four propeller-type engines and a pressurized cabin. Tests conducted by NACA and actual ditchings clearly indicate that
the ditching characteristics of the C-118 and other low-wing pressurized aircraft are good.
Of the many factors to consider in ditching an aircraft, weight and speed at touchdown are probably the
most critical. A reduction in weight will reduce the forward momentum after touchdown. This will provide for a shorter deceleration period and a reduction in impact force. A short runout or deceleration is
particularly important when the distance between swells is relatively short such as in the Atlantic Ocean. Dumping or consuming fuel will also improve the buoyancy of the aircraft. The forward speed of the aircraft
at touchdown must be as low as possible, consistent with the desired angle-of-attack and gross weight. I would recommend an attitude of 17 to 18 units angle-of-attack with the power levers at or near FLIGHT IDLE
position upon impact. The expected G-force at this ADA is estimated at 2 Gs. Runout distance should be about 600 ft.
The swell is the primary factor in evaluating the sea for ditching, since it
normally is the greatest force or factor. In the event that essential information concerning the sea conditions is not available from a ship in the local area, the sea may be evaluated through the use of smoke. Do
not attempt to evaluate the sea conditions at extremely low altitude since there are usually two or more swell systems in the open sea. Combined with the height of the swell, currents and wind conditions, the sea
will appear confused at low altitude. The primary swell is more apparent at altitudes between 1000 and 1200 ft, depending upon light and sky conditions. After selecting a ditching heading based upon swell
evaluation, the heading should not be altered more than 10 degrees. Serious considerations should be given to the relationship between swell and wind direction. With winds from 0 to 35 kts - land parallel with the
major swell and downswell to the secondary swell system. Winds over 35 kts - land into the wind since the reduction in groundspeed will improve the overall ditching problem. A successful open-sea ditching of a
low-wing four-engine transport was accomplished alongside an ocean station vessel in a crosswind of 40 kts. It is interesting to note that in this ditching a second impact did not occur.
When
ditching parallel to the swell, a crosswind will usually be present so that crabbing is needed. Do not lower the wing more than is necessary. Attempt to touch down on the receding (back) side and near the top of the
crest, parallel with the swell. Do not attempt to land on the face of a rising swell. At night or under instrument conditions when sea conditions are not available, the best course of action is to use the known
surface wind and set up a landing pattern in that direction.
The wing flaps in all probability will be carried away at touchdown and, therefore, will not provide a plane to give a nose-down action.
It can be expected that the propellers will separate from the gear box upon contact with the water and will pass beneath the wing. The props did not exhibit a tendency to walk the water in the latest accident as
they will do on firmer terrain (runway, ground, etc.); therefore, there is no necessity to secure an operative engine prior to ditching. Ditch while power is available using minimum asymmetric power to reduce the
minimum control airspeed (Vmc air). When the approach is made with power, the aircraft may be dragged along the approach path until a comparatively calm sea is found for touchdown. While this procedure is
permissible, it should be emphasized that the judgment of height, particularly at night, will be difficult; therefore, during darkness it would be preferable to establish the lowest possible rate of descent and
maintain this descent until contact.
After touchdown, the aircraft should be held on the water. This does not mean that the control column is to be forced into the full nose-down position.
Conversely, the control column should not be pulled full back, or nose-up immediately after contact, since it is possible for the aircraft to become airborne again. The resultant stall and damage can be
considerable. The force to be applied to the control column will depend upon the planing action encountered. That is, when an appreciable nose-down or nose-up force is felt, an approximate counteracting force should
be applied. Unless the pilot has had previous experience in seaplanes, a neutral position of the control column throughout the runout is recommended. The runout is relatively short and the design of the landplane
fuselage does not indicate that an appreciable change in attitude can be accomplished in the time available.
This information is not intended to replace, but to supplement the ditching/bailout
comments contained in the P-3 NATOPS Manual. Remember that safe ditching
of an aircraft requires maneuvering control and power. If and when the conditions prevail, make your decision to bailout or ditch and stick
with it.
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