"I've been kicked in the ass harder than that..."
-- Jim Hall |
These questions led to a unique test. In the mid-1960s a firm that had made its name providing ejection seats and egress technology to both the military and to NASA decided that instrumented dummies did not provide all the information needed. They felt that certain questions of human physiology needed to be answered by a test of a live human. Weber Aircraft's seats had saved over 500 lives by this time. They had been fitted to such varied craft as the F-106 and the Gemini Space capsule. The F-106 seat included the latest technologies available to allow for a clean ejection, including a gun deployed parachute, rocket motor, and self deploying survival equipment.
In late 1965, Jim Hall a professional parachute safety instructor and Major in the Air Force Reserve volunteered to act as the human guinea pig for the 0-0 seat package. He was instructed in all facets of the seat operation. He viewed films of the 43 sequential successful tests of the F-106 0-0 system. He also was measured for center of gravity in order to align the rocket exhaust with the center of mass of the man-seat package. In the tradition of the day, he visited the assembly line and selected the particular seat he would later ride.
The engineers checked and verified all functions of the particular seat. They selected a lake not far from the factory for the test. A set of seat rails were attached to a test stand. The date and time were selected. And then it was time.
Jim Hall, accompanied by a platoon of engineers, arrived at the site and was shown the seat. Now it was mounted on the rails, wired and ready to fire. Every mechanical function had been checked and double checked. Major Hall was attired in an orange flight suit. Its arms were cut away at the shoulder to reveal a small area of skin that had been marked by pigment. He was strapped into his chute and assisted into the seat. All the straps were connected and tightened. The engineering cameras were armed to record every aspect of the test, even the slump of Jim's shoulder markings under launch acceleration. Then the engineers withdrew to a safe distance. The rescue launches on the lake were signaled, and the countdown began...
Major Hall gripped the handles built into the sides of the seat bucket and pulled them up to the firing position... and nothing happened... for one long second. The delay cartridge allowed the high speed cameras to get to speed and then the hot gas was unleashed into the catapult initiator. The Major rose up the rails with anonset rate of 150 g's/second with a maximum of about 14g's. The rocket ignited as the seat cleared the rail providing the huge jet of flame in the above picture. One second and almost 400 feet later, seat separation occurred. The parachute gun fired, and two seconds later the parachute was fully inflated. The survival kit automatically released and dropped to the end of its lanyard. The rubber raft, suspended from the same lanyard,immediately inflated.
Approximately 26 seconds after Major Hall pulled the handles he landed in the lake.A journey of only a few dozen yards had taken him to an altitude of about 400 feet andinto the history books (albeit only a few obscure ones...). To this day, thirty-three years later, Jim Hall's zero-zero ejection test remains the only 0-0 test that was executedwith a human subject in the United States by an American Company. (The first known live 0-0 test was executed in 1961 by Martin-Baker Aircraft Co. Inc.. Doddy Hay, a M-B employee, was the 'Man in the Hot Seat' for that first test. There have been several other live tests, most of which have been at altitude, or with some airspeed.)
Special thanks to Gordon Cress (Project Test Engineer: Project 90) for providing the information and the photograph for this page.