Eject, Eject - The evolution of the Aircraft Ejection seat
Well before the first jet aircraft entered production there were already significant concerns for the safety of pilots and aircrew as aircraft speeds increased, it was not just the problem of egress but that of avoiding being struck by the aeroplane after successfully leaving the cockpit. The germans experimented with several types of ejection seat or Schleudersitzapparat (seat catapult device) and had determined that the human body could withstand a G force onset of around +20g for up to 0.1 seconds. The initial preference was for a compressed-air powered seat, one of these being developed by and fitted to the prototype HE280 jet fighter by Heinkel who would maintain chief engineering responsibility for aircraft escape systems throughout the war.
The seat proved a life-saver for Heinkel test pilot Helmut Schenck who was forced to eject from HE280-v1 on the 13th January 1943 when its controls iced up after being towed into the air to test the pulse jets recently fitted to the aircraft. The compressed air seat that saved Schenck was later discarded in favour of one using a propellant charge to force the seat from the aircraft. In this new design the seat was mounted on 42 inch long parallel catapult tubes containing a one ounce charge which when fired achieved an ejection velocity of 35 feet per second an imposed a 12g load on the pilot. The German's installed ejection seats in the Heinkel He-162 Volksjäger, Arado Ar-2348 Nachtigal and Messerschmitt Me-163 Komet but not strangely in the ME262 despite it being used in the greatest numbers, by the end of the war approximately 60 Luftwaffe airmen had ejected from their planes in combat situations.
To be continued ...
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