by Tommy H. Thomason

Wednesday, October 19, 2011

Yankee Tractor Rocket Escape System

The retrofit of the Air Force A-1 Skyraiders, both single seat and wide body, with the Stanley Aviation Corporation Yankee escape system is fairly well known. As it turns out, this was a Navy initiative and at least two squadrons had their aircraft modified with this capability, VA-25 (Coral Sea) and VA-152 (Oriskany). It is properly described as an extraction system as opposed to an ejection seat, since the seat stays in the aircraft and the pilot is pulled out by the rocket as opposed to being pushed out.

VA-25

VA-152

The retrofit was fairly simple. VA-25 reportedly had all 12 of its aircraft modified midcruise in a couple of weeks at NAS Cubi Pt, Philippine Islands in November 1967 while Coral Sea was off the line. It basically consisted of a rocket located under the canopy behind the pilot's head and a different seat/headrest. The rocket was connected to two ten-foot lines that were attached to the pilot's parachute harness.

The rocket was installed to the right of the existing canopy actuation mechanism.
(Note that this mechanism was usually covered by canvas before the Yankee seat was installed.)

When the pilot activated the system by pulling a D-ring located between his thighs, the canopy was jettisoned and the rocket tilted upward and fired, extracting the pilot out of the cockpit. This is a test using a civil-registered T-6G.
The system was rated for zero airspeed and zero altitude but only with zero sink rate and zero pitch/roll. A zoom climb was therefore recommended before jettisoning the airplane.

Although light weight, the extraction concept was only appropriate at the relatively low speeds usually attained by propeller driven aircraft.

For more stuff on the Yankee seat, see:
http://skyraider.org/skyassn/otherpics/cole/Yankee.jpg
http://skyraider.org/hook/dashonet/yankee.htm
http://users.bestweb.net/~kcoyne/frame_sg.htm (Click on the Stanley "Yankee" button well down in the left column )

For a comparison with the original seat, see http://tailspintopics.blogspot.com/2013/11/ad-1-skyraider-standard-vs-extraction.html

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