History of Research in Space Biology and Biodynamics
 
 
- PART IV -
 
Other Work on the Escape Problem
 
 
 
[53] Although high-speed track studies of windblast and deceleration have been the main Holloman contribution to research on the escape problem, they do not represent the Center's entire effort. Another unique Holloman facility that has been used for this research is the 120-foot short track, or Daisy Track as it is usually called. This track was completed in 1955, precisely for aeromedical research, and is operated under the general auspices of Task 78503 (of Project 7850), Tolerance to Impact Forces. The Daisy Track is a versatile research tool, and its performance range has nicely supplemented that of the more famous long track. The majority of the work related to its use will be described in detail in a later monograph, since its purpose is to accumulate basic research data on human tolerance to as broad as possible a range of g-forces, in all planes of body orientation, rather than to support a particular program of applied research. However, data acquired on the Daisy Track are relevant to a great many specific research problems, of which not the least has been the problem of escape from aircraft. From the viewpoint of anyone who must deal with that problem, obviously, the more data become available on g-tolerances, the less room there is for guesswork in what is a matter of life or death.
 

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54] (MISSING PHOTO)
Project High-Dive Dummy Launch
 
[55] Colonel Stapp's experiments on the long track supplied data on tolerance to deceleration such as a pilot encounters from wind drag following actual ejection from the aircraft, but Daisy tests-to cite one concrete example-have added information on tolerance to the g-forces involved in propelling the ejection seat itself (or other escape device) out of the aircraft. To clear the high-flying tail of modern jet planes a powerful thrust is needed, and therefore both Air Force and aircraft industry representatives have been interested to learn that human volunteers on the Daisy Track have sustained slightly over thirty g's in a position for upward ejection (g-forces parallel to the spine) with no lasting ill effects. It had formerly been thought that anything above twenty-four g's in this position threatened spinal injury, but designers now appear to have a little more leeway. The Daisy Track has also been used to explore g-tolerances in the special position assumed for riding the experimental Convair "B" ejection seat which is discussed below. And it has been used in certain cases to test new harness designs and other specific items of equipment, both for crash restraint and for actual escape from aircraft.50
 
A somewhat different type of research, though still related to escape from aircraft, was conducted by Colonel Stapp in April 1957 amid the dunes of White Sands National Monument, which is wholly surrounded by the Holloman-White Sands Proving Ground integrated test range. The aim was to explore the possibility of remaining fastened in an ejection seat throughout parachute descent. For this purpose, a human subject would take his place in an ejection seat, which in turn was attached to a small plastic balloon; he then rose up in the air a short distance and came down with the balloon itself taking the place of a parachute. Impact velocities gradually increased until they began to approach standard parachute-landing speeds. Volunteer participants in these tests reported some discomfort, but it was agreed that the procedure was well worth exploring further.51
 
In addition to the research efforts of its own Aeromedical Field Laboratory in the area of escape from aircraft, the Air Force Missile Development Center has collaborated in related efforts by the Aero Medical Laboratory at Wright Field. One example is the "manned balloon flight" program that was made a task of Wright Air Development Center's Project 7218, Biophysics of Escape (now replaced by Project 7222: Biophysics of Space Flight), and is often referred to by the short title High-Dive. This program actually dates back to the period when Colonel Stapp was previously assigned to Wright Field, before coming to Holloman, and it was then regarded as a "first step in the development of a floating laboratory for a variety of upper atmosphere studies."52 However, a more immediate objective was to have human subjects stage experimental parachute jumps from balloon gondolas at altitudes ranging up to approximately 100,000 feet, and this objective was of obvious importance for aircraft escape procedures.
 
Colonel Stapp not only helped in the preliminary planning for this program while he was at Wright Field but continued to follow its development with interest after his arrival at Holloman. Other officers of the Aeromedical Field Laboratory were also interested, lending their cooperation when needed. The chief concrete support rendered at Holloman, however, came from the local Balloon Branch, which had the task of conducting balloon flights for the Wright Field project. The first launch attempt, on 1 May 1953, was unsuccessful, but launchings continued intermittently thereafter. Flights were made to test balloon performance, parachute equipment, and gondola systems; and anthropomorphic dummies took practice jumps for various purposes, accumulating data on free fall or exploring the characteristics of stabilizing parachutes. A few launches were made in the fall of 1955 on behalf of Twentieth Century Fox, which included a Hollywood version of this project in the same motion picture, "Threshold of Space," that featured Colonel Stapp's sled rides.
 
Project High-Dive also encountered numerous delays, however, and the proposed manned balloon flights have not yet taken place. One of two balloon gondolas developed for the project was appropriately named "[On-Again, Off-Again] Finnegan." Project officers came to Holloman Air Force Base in the fall of 1957 for another series of dummy tests leading up to the actual live bailouts; but before much else was accomplished there was a change of plan in order to provide experimental testing of an escape system developed for the X-15 rocket aircraft. There has also been a change of name, from "High-Dive" to "High-Chair." In effect, the special X-15 ejection seat and allied parachute equipment will be dropped in various tests from a stratosphere balloon, and in the scheduled manned experiment from 97,000 feet the test subject is to ride all the way up in the seat itself rather than in a balloon....
 

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56] (MISSING PHOTO)
Cherokee Missile Used in Project Whoosh
 
[57] gondola. What else may finally develop out of the Aero Medical Laboratory's manned-balloon program remains a matter of conjecture. Meanwhile, Holloman's own Project Man-High, as described in an earlier monograph, has definitely taken the lead as far as creation of a balloon-borne "floating laboratory" is concerned.53
 
Still another cooperative venture between Holloman and Wright Field with a direct application to the escape problem was Project Whoosh, which aimed to "evaluate escape from a high speed aircraft at approximately Mach 2."54 The project involved ejection of chimpanzee subjects, from a specially-designed Cherokee missile. The missile was to be taken aloft by a modified B-29 bomber and then accelerated to supersonic speeds before the anesthetized subject, strapped into an open ejection seat, was shot out from the missile's interior. Direction of this activity was assigned principally to the Aero Medical Laboratory at Wright Field, where it became another aspect of Project 7218, Biophysics of Escape, but Colonel Stapp and others at Holloman participated extensively. The Aeromedical Field Laboratory supplied chimpanzees, and Holloman Air Force Base was the site for several of the actual tests.55
 
The first two live ejections took place at Edwards Air Force Base, California, on 26 January and 8 June 1954, at speeds of mach 1.1 and mach 1.5. Then, in 1955, all testing activity shifted to Holloman, where superior range instrumentation and chimpanzee quarters were available. Two low-speed control studies were made in July, dropping seat and subject from a C-47, without benefit of Cherokee missile. They were followed by two more supersonic ejections on 21 October 1955 at mach 1.5 and 3 April 1956 at mach 1.4, both times bringing the project B-29 (which happened to be the X-1 mother ship) all the way from Edwards at considerable cost in time and overhead. Problems of coordination were multiplied several times over for the last test by confusion and misunderstandings at command headquarters, Wright Field, Holloman, and Edwards as to whether the entire project was or was not being cancelled. It was cancelled beyond any doubt soon after the final Holloman test. Not one of the animals ejected at supersonic speeds had managed to survive, for in each case there were equipment difficulties (with parachute system or ejection seat) that led to death of the subject and overshadowed any possible evidence of injury through supersonic windblast, tumbling, and deceleration. Nevertheless, the project was not a total loss. Even the failures were instructive, and the work performed on Whoosh led directly to further ejection experiments at the Supersonic Military Air Research Track, Hurricane Mesa, Utah.56
 
This last track is an off-base facility of Wright Air Development Center and is especially well suited for tests of escape systems. The track leads straight to the edge of a cliff, and objects fired from a supersonic sled are then lowered by parachute to the canyon floor 1,500 feet below. In a sense, Whoosh operations were simply transferred from mid-air to the track at Hurricane Mesa, with the Aeromedical Field Laboratory still supplying chimpanzee subjects and still taking a direct interest in the proceedings. During the fall of 1956, five chimpanzee subjects were ejected at speeds of about mach one, using a special ejection seat designed for testing rather than for operational use, and three were recovered uninjured. These successful ejections ranged from .95 to 1.15 mach. In March 1957, a chimpomorphic dummy was ejected successfully at mach 1.1, but the next attempt in the series, again using a chimpanzee, was unsuccessful; in fact the sled itself was wrecked.57
 
Meanwhile two members of the aircraft industry, Lockheed and Convair, have been making significant progress with improved ejection seats of unusual design. Each has been specially commissioned to do so, on behalf of the industry as a whole, by the Industry Crew Escape Systems Committee. The Lockheed seat, intended for downward ejection, uses a skip-flow generator somewhat resembling the small bug-deflecting devices often mounted on the hood of automobiles. In Colonel Stapp's words, this "ingeniously surrounds the escapee with an atmospheric capsule, and is an impressive device to extend the range of the ejection seat." In April 1957 this experimental Lockheed system was tested on the Holloman high-speed track, and it has also been tested (with anthropomorphic dummies) at Hurricane Mesa.58
 
The Convair "B" seat, which is designed for upward ejection, is chiefly distinguished by the telescoping booms that are extended during the ejection process and give the seat a remarkable stability in the air. It is lifted to a horizontal position atop the plane before being fired into the airstream; the pilot then rides feet-first, with knees tucked up and with the rounded bottom of the seat giving added protection. This seat, too, has been track-
 

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58] (MISSING PHOTO)
Test of Lockheed Ejection Seat on Holloman Track
(MISSING PHOTO)
Convair "B" Seat Mounted for Track Testing
 
[59] tested, at Hurricane Mesa and at Edwards Air Force Base. It is one of the most promising of all recent escape devices, although naturally the maneuver of raising the seat into position for firing from a crippled aircraft poses some rather complex problems. However, work toward solving these and other problems has been going ahead on several different fronts. One such front is the Aeromedical Field Laboratory, where tests on the Daisy Track have clearly established human tolerance for the predicted g-forces in the exact body position required for riding the Convair seat.59
 

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