The Ejection Site

Stanley YANKEE Extraction System

One of the oddest egress systems ever designed, the Stanley YANKEE system was utilized in the Douglas A-1 Skyraider. This system functions by means of a extraction rocket similar in principle to the drogue gun systems on normal ejection seats. Once the catapult charge fires, the spin stabilized rocket is fired when the pendant lines reach full stretch.

Actuation of the system is effected after jettison of the canopy. The rocket then is erected by means of a pyrotechnic piston and lever under the erector/launcher. The rocket is then launched from the rear wall of the cockpit and by means of a pair of Perlon pendants (rope-like straps) pulls the pilot up and out of the cockpit. The parachute is rigged with an automatic opening system which is activated after the rocket pendants separate from the parachute risers. The system includes a set of rails to allow the seat back to rise up and the seat pan is articulated to assist in the positioning of the pilot to the vertical as the rocket extracts him.

The A-1H system shown is the cockpit section of a crashed Skyraider. The aircraft was belly-landed on a runway and was determined to be not worth the cost of repair so the fuselage was cut up and the cockpit retained as a trainer.

The system was effective from 30kts at ground level (wings level). I have heard that it was effective for crewmen over the normal weight limits.

The system was considered for use in the NASA Space Shuttle and testing was done to prove that the rocket could extract an astronaut via the side crew entry hatch. It was rejected for various weight and space reasons. The Shuttle now is configured with a boom system that extends out of the crew hatch to provide a sliding exit for the astronauts. The astronauts would slide out along the boom and manually activate their parachutes.

Currently the system is owned by Universal Propulsion Co. which purchased some of Stanley Aviation's designs a few years ago. The system is now known as the RANGER system.

External view showing the tractor rocket and erector
Note the black lever and the partially hidden piston of
the erection system just aft of the cockpit bulkhead.
Front view of the rocket and the perlon pendants
The rusted section contains the nozzles of the rocket,
which are angled slightly to spin stabilize the rocket.
The seat with the perlon pendants attached to the parachute risers
The seat pan showing the firing handle.
Drawings of the YANKEE System and its functions
General Seat arrangement
Canopy Jettison
Tractor catapult charge firing
Pendant lines stretch full
Crewman begins movement
Crewman/aircraft separation
Parachute Auto system arms
Diagrams Courtesy Byron Hukee, Former Skyraider Pilot
and his
The Official Douglas A-1 Skyraider Site

The A-1H Cockpit section was on display at the SAFE Association History of Escape Systems and the Evolution of Manikins Display during the SAFE Association 40th annual Symposium, October 2002

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