A comment on ensuring landing gear down if forced landing a retractable gear aircraft
Issue No. 18 of ATSB Aviation Short Investigation Bulletin contains a report on the apparent double engine failure in cruise of a PA-39 Twin Commanche VH-RMA.
The following excerpt makes interesting reading:
Concerned about the aircraft’s proximity to the critical V
mca3 airspeed (70 kt), the pilot maintained about 90 kt, while searching for a suitable landing site. He commenced an approach and broadcast the aircraft’s position and his intentions on the Melbourne Centre frequency. On final approach, he turned off the fuel pumps. During the round-out, he decided to extend the landing gear, as the surface looked more suitable than first thought. He pulled back on the control column to gain height and selected the landing gear down. The aircraft stall warning briefly sounded, so the pilot lowered the aircraft nose. Moments later, the propellers contacted the ground and the aircraft skidded to a halt.
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In the old days of predominately tail-wheel aircraft, it was considered safer to land wheels up in a forced landing to prevent the aircraft from nosing over on touch-down. This was vital in the cases of fighter aircraft such as the Spitfire, Hurricane and Hawker Typhoons and Tempests -all of which were retractable main landing gear types with tail wheels.
When the North American Sabre jet fighter was introduced into the United States Air Force it had a tricycle landing gear with a nosewheel. Initially pilots would continue with the then policy of landing with the wheels retracted on a forced landing. The higher landing speed associated with jet types often resulted in severe back injury to the pilot in a forced landing gear up as there was no energy transfer to the landing gear on impact and the force of impact often caused spinal injuries.
Because of this danger, it became standard procedure to land wheels down in event of a forced landing in a tricycle landing gear type. Impact forces through the spine were reduced because the landing gear absorbed most of the energy; especially if a high rate of descent was occurring at the flare. Also it may be possible to reduce the landing run by use of the wheel brakes if they are available. Of course this did not apply to ditching, where wheels up applied to all types.
It took many years for the civilian training community to accept the military recommendation to lower the landing gear in a forced landing in a tricycle landing gear aircraft. Even now it is doubtful if the word has been passed down to flying school instructors and I wonder if this was the reason for the pilot of the afore-mentioned Twin Commanche to plan for a gear up belly landing in his aircraft after both engines played up and a forced landing became necessary.
The ATSB report indicated he tried to lower the landing gear just before he flared when he saw the field was suitable for a gear down landing. The point could have been made in the ATSB report that experience has shown a wheels down forced landing has its advantages over a belly landing, almost regardless of the surface (apart from ditching). Even with a rocky surface, it would almost certainly be safer wheels down because of the energy transfer to the wheels rather than the bottom of the fuselage and directly to the pilot's seat and spine.
I wonder if this sort of airmanship consideration is actively taught at todays flying schools whether on single engine or twin engine retractable landing gear types?