While Armstrong was learning to fly by reaction controls, the X-15’s design was frozen. A full-scale wood and soft metal mockup painted black was hidden behind a walled-off area marked SECRET. For the men who had brought it to life, the sight of the mockup filled them with an overwhelming sense of pride. Everything fit, and the weight was within acceptable limits. To the untrained eye, the mockup was so precise it looked like it was ready to fly.
When Walt Williams, Scott Crossfield’s former boss from the High Speed Flight Station, arrived at the Los Angeles factory to inspect the mockup on behalf of the NACA, he was as anxious to get his hands on the research aircraft as Crossfield was to take it for a test flight. Poking his head into the cockpit and touring around the fuselage, Williams fired questions at Crossfield, who knew the aircraft in such intimate detail that he could answer every one without hesitation. An air force officer also inspecting the mockup challenged Crossfield as to why there was no landing gear position indicator in the cockpit. Crossfield explained that when the X-15 was coming in for a landing at two hundred miles per hour with no engine power to make a second attempt, it wouldn’t matter whether the landing gear was down or not; it was going to land. The wiring and cockpit indicator light simply wasn’t worth the extra five pounds. The X-15 passed this first inspection with about a hundred requested changes, far fewer than the team had anticipated. The hypersonic aircraft could finally move into the construction stage.
By the end of the year, the next generation of flight research was on the cusp of taking to the skies with Armstrong training with space-age reaction controls and the X-15 coming to life. For the NACA, the air force, and North American Aviation alike, the aircraft couldn’t start flying soon enough. Mel Apt’s death not only highlighted the unknowns that continued to stand in the way of aircraft giving way to spacecraft, the loss of the X-2 marked the loss of the most advanced rocket aircraft. The X-15 was needed to fill this new void in research vehicles. But there was one question the X-15 couldn’t answer and that was what would happen to men at near-space altitudes over a prolonged time frame because follow-up vehicles would take men higher into space for longer stretches of time, exposing the human body to radiation from space and a host of unknown problems. The X-15’s flights would be too short to really probe the biomedical questions of what a human could tolerate on a high-altitude flight. But elsewhere in the country experts were devising ways to gather the human data the rocket plane couldn’t.
CHAPTER TEN
The Floating Astronaut
Hardly anyone knew who John Paul Stapp was when he arrived at Muroc Air Base in the spring of 1947. The U.S. Air Force flight surgeon kept largely to himself, working closely with a skeleton crew of civilians he had brought with him from the Northrop Corporation out of Los Angeles. Stapp quickly gained a reputation for operating something of a black market on the base. With barely any funding or resources to bring their project to fruition, Stapp bartered, trading medical advice and examinations for the parts and equipment his team needed. However nontraditional Stapp’s method, there was nothing nefarious about his actions. His project was sanctioned by the air force, albeit at such a cripplingly low level of bureaucracy that he was left painfully underfunded. The silver lining was that his low priority kept him off the radar of the higher levels, the men Stapp envisioned spending their lives safely behind large mahogany desks, men who he knew would penalize his failure but take credit for his success. Operating under their radar made him solely responsible for either outcome, but also afforded him great freedom.
Gradually and discreetly, Stapp’s team built a sled reminiscent of a soapbox racer though this one was made of spare aluminum pieces bolted together rather than a wooden crate. It had a seat for a pilot and, appropriately for Muroc at the time but untraditionally for soapbox racers, a bank of rockets strapped to its back. The sled sat at one end of a two-thousand-foot-long track. At the other end was a braking system designed to stop the sled instantly, the sudden deceleration subjecting its unlucky occupant to a sudden high load of g-forces. This was the unorthodox contraption’s purpose, to simulate what a pilot would experience in a high-speed crash. Textbooks said the limit of human tolerance was 18 g’s, or eighteen times the force of gravity. Stapp’s research was dedicated to determining whether, as he suspected, man could tolerate far more. The first step in his human deceleration research was this soapbox racer sled nicknamed the Gee-Whizz.
The Gee-Whizz first raced down its track with a 185-pound humanoid dummy in its seat. In December, after thirty-five test runs, Stapp took the dummy’s place. One rocket was fired on the first manned test of his program, sending Stapp tearing down the two-thousand-foot-long track at a relatively easy ninety miles per hour. The next day, he was back in the Gee-Whizz when three rockets were fired, more than doubling his speed to two hundred miles per hour. Every time the sled came to a halt Stapp was exposed to a punishing load of negative g-forces when he slammed against the harness keeping him in place. The heavy bruising he sustained, along with abrasions, broken ribs, concussions, and even lost fillings, didn’t deter Stapp. The tests left him battered but invigorated. Riding the Gee-Whizz, he survived a maximum load of 35 g’s, thirty-five times the force of gravity, proving that men can withstand far higher forces of deceleration than anyone had previously thought.
News that Stapp was using himself as a test subject eventually made its way to his home laboratory, the Aeromedical Laboratory at Wright Field outside of Dayton, Ohio, though it was hardly a surprise. Stapp had a reputation for using himself as a test subject. He had once flown to forty-seven thousand feet in an unheated, unpressurized cabin just to experience the painful effects of the bends firsthand. It was a line of research that led to Stapp’s discovery that a pilot could avoid the bends by breathing pure oxygen for a half hour before takeoff. But the rocket sled runs were too much for his horrified superiors at the Wright Field and, fearing he might kill himself, Stapp was ordered to cease sending humans flying down the track in his sled and use chimpanzees instead.
The NACA contingent at Edwards, however, was very interested in Stapp’s human research. Being in the business of high-performance aircraft poised to push inexorably toward space, the NACA was interested in the human element of spaceflight, particularly the acceleration and sudden deceleration a pilot would experience when launching on a rocket. This interest prompted Stapp to defy his orders and reclaim his seat in the Gee-Whizz for the sake of the NACA’s research.
By June 1951, volunteers had made seventy-four runs in the Gee-Whizz’s nearly four years of operation, Stapp himself being its most frequent rider. But the sled at Edwards wasn’t enough for the flight surgeon who wanted to reach faster speeds for more violent decelerations. Stapp’s opportunity for a new phase of research came with his transfer to the Holloman Air Force Base in New Mexico, the site adjacent to the White Sands Proving Ground. Stapp arrived in New Mexico in 1953 and, still working with engineers from Northrop, built a far more powerful rocket sled called Sonic Wind No. 1. This sled featured a replica of a jet pilot’s seat, a full propulsion section at its back end, and a simple but effective water brake system at the far end of the track. A scoop attached to the underside of the sled would dig into a series of dams between the track’s rails. Resistance from the scoops digging into the water would stop the sled almost instantaneously for the hard deceleration Stapp wanted.
As was his way, Stapp used himself as the first human subject for the Sonic Wind’s speed run. In March 1954, just six of the nine rear-mounted rockets ignited to propel the sled to the brief top speed of 421 miles an hour. It was a land speed record, and when the sled stopped Stapp was subjected to 22 g’s. Unsatisfied, Stapp added more rockets and more aims to the program. Because the sled had no windshield, the faster runs were also a way to gather data on human tolerance to wind blasts, something else pilots would experience in high speed ejections. And he remained the test subject.
On December 10, almost seven years after his first rock
et sled run in the Gee-Whizz, Stapp was strapped into the seat of Sonic Wind No. 1 as it sat at the end of its track at Holloman. His arms and legs were secured to stop them from flailing. He wore a helmet, which was strapped to his headrest to protect him from whiplash. He had a bite guard in his mouth to protect his teeth. He also had a crew spread around the desert. Technicians running the test were on hand and photographers were ready to capture image data of the test, specifically the final deceleration. In the sky, air force pilot Joe Kittinger was waiting in a T-33 jet, prepared to fly over the end of the track at the moment of deceleration so the photographer seated behind him could capture the test from above. The timing for everyone was crucial, as were clear skies for the sake of images. Behind the sled’s seat that morning was a cluster of nine solid fuel rockets that together produced forty thousand pounds of thrust. Stapp was only going to subject himself to this high-speed run once. Everything had to be perfect.
Once the morning clouds broke, the countdown for the test started. With a thunderous roar, the nine rockets came to life and in five seconds Sonic Wind reached its top speed of 632 miles per hour. Stapp was thrown against the back of his seat with the burst of speed, briefly losing consciousness. Overhead, Kittinger watched as the sled flew across the desert floor faster than his T-33 jet. Then the scoops dug into the water trenches, sapping the sled’s energy and stopping it cold in just 1.4 seconds. The sudden deceleration subjected Stapp to 46.2 g’s. He momentarily felt his body weigh sixty-eight hundred pounds as he slammed forward against his restraints with the same force as if he had smashed into a brick wall while driving his car at 120 miles per hour. And then the sled was still.
Immobilized by his restrains, Stapp felt unbearable pain. He was struggling to breathe. As emergency personnel removed him from the Sonic Wind’s seat, he mumbled that he couldn’t see, that he had somehow gone blind. Stapp was rushed to the hospital for a thorough medical examination, but amazingly the doctors found that he had sustained no critical injuries. He had cracked ribs, two broken wrists, burst blood vessels in his eyes, and minor damage to his circulatory and respiratory systems, but he was otherwise fine. After an hour in the hospital, Stapp had regained his eyesight and was eating a hearty lunch. Stapp wanted to push his rocket sleds further. Before he had fully recovered, he was already planning to add more rockets to Sonic Wind No. 1 with the goal of reaching one thousand miles per hour, fast enough to break the speed of sound. But the air force stepped in and grounded him from any more rocket sled runs for his own safety.
Though banned from further rocket sled tests, Stapp had other outlets for his curiosity. Wright Field was home to the Materiel Division of the U.S. Army Air Corps, the branch responsible for developing advanced aircraft, equipment, and accessories. This branch’s activities made the Ohio site’s name synonymous with developments in aeronautical engineering and innovative research. Not long after Stapp arrived in 1946, he had witnessed one such test on a warm day in June. Three men sat on the grass wrestling a crash-test dummy outfitted in a standard flight suit and cap into a simple seat. Once they had it strapped in tight, the dummy and seat were hoisted by a crane and lowered into the uncovered cockpit of an aircraft parked nearby. Six technicians ensured everything was in the right place before tying a rope to the back of the seat. The end of the rope was in the hand of another man who also sat crouching in the grass. The crowd of onlookers moved a safe distance from the aircraft, which in this case was just feet away. Then the man in the grass pulled the rope. In an instant, the seat carrying the dummy shot up and backward, tracing a high arc over the aircraft’s tail. Both landed separately, the dummy in a net and the seat nearby on the ground. The landing was irrelevant; it was the explosive ejection that mattered, a novel concept pioneered by the Luftwaffe during the Second World War that was fast becoming a fundamental part of American aviation.
The test underscored something interesting for Stapp. The state of the art of aviation was advancing as rockets propelled aircraft higher and faster, but human pilots weren’t getting any more robust. The disparity between increasingly powerful aircraft and human frailty became a research niche for Stapp. Deceleration tests were a part of the subsequent investigation, but tests of human tolerance to extreme environments was another pathway. Higher flights meant men would soon be visiting the upper reaches of the atmosphere, a poorly understood region particularly where human factors were concerned. These men would be dealing with radiation from space, exposure to a near vacuum, and undoubtedly psychological challenges.
Aircraft, Stapp knew, wouldn’t be a suitable means to investigate the human factors of spaceflight. For all their technological complexity and sophistication, the rocket planes streaking through the skies over Edwards Air Force Base gave the pilot only brief exposure to upper atmospheric conditions before falling back toward the dry lake bed. Even the X-15’s highest altitude flights would only expose the pilot to space radiation for a few minutes. The pilot would need a specialized flight suit, but he could essentially ignore issues of radiation. Balloons would put the pilot in the exact opposite situation. Rising to altitude slowly as the lifting gas in the cavernous envelope expanded, a balloon could theoretically stay at altitude for an extended period, exposing the pilot to space radiation long enough to gather data. Stapp earmarked balloons as the ideal test bed for this line of research. He imagined a balloon large enough to carry a pressurized high-altitude capsule beneath it that could serve as a floating laboratory. When Stapp arrived at Holloman in 1953, he established and assumed responsibility for the Aeromedical Field Laboratory, a major goal of which was to understand the hazards to humans in the upper atmosphere. Foremost were questions of cosmic rays coming from deep space and radiation exposure, and specifically cosmic ray bombardment of living tissue.
David Simons saw the same shortcomings in small, suborbital sounding rockets that Stapp saw in rocket aircraft flights. Not only did Simons want a longer exposure to the upper altitude, he needed a more reliable way to recover the biological specimens. The Alberts monkeys stood as a prime example. The first primates in space launched under Simons’s guidance had fared horribly in the nose cones of their V-2 Blossom rockets. In seeking a means to study the effects of high-altitude flight on living beings, Simons also saw balloons as the best option.
Balloon flights had changed dramatically in the nearly two centuries since Joseph-Michel and Jacques-Ètienne Montgolfier launched a sheep, a duck, and a rooster in the open basket of a hot air balloon over southern France in 1783. And it was due in large part to Otto Winzen. After spending a large portion of the Second World War in an internment camp, the German-born aeronautical engineer was hired as the chief engineer at the Minnesota Tool and Manufacturing Corporation. It was here that Winzen was introduced to the world of ballooning. In late 1945, he was recruited by Swiss balloonist Jean Piccard to work on Project Helios, a joint program by the U.S. Navy, the National Science Foundation, and General Mills that would see a man launched up into the stratosphere. Winzen was ultimately recruited by General Mills to work on balloon development and establish the company’s Aeronautical Laboratories, a branch whose usefulness persisted after Helios was canceled.
At General Mills, Winzen helped advance the science of ballooning. He developed a way of heat sealing plastic gores together and developed a load-bearing tape to seal these joints such that the weight of a balloon’s payload was evenly distributed over its entire surface so the material was less likely to tear. He also developed a polyethylene balloon that soon took the place of rubberized ones. Though typically just one or two thousandths of an inch thick, the exceptionally strong plastic was resistant to expansion once the balloon was fully inflated, decreasing the likelihood of it bursting at altitude. Winzen’s polyethylene balloons were also able to take advantage of a gas’s expansion. A small amount of a lighter-than-air lifting gas could be pumped into the balloon on the ground. As it rose, the Sun’s heat combined with the lower atmospheric pressure would cause the gas to expand t
o fill the balloon’s full volume. Winzen launched the first balloon of his own design in September 1947. The next year he left General Mills to start his own balloon manufacturing company, Winzen Research, Inc., based in Minneapolis. The startup money came from his in-laws; his wife, Vera Habrecht, was the wealthy daughter of a society photographer from Detroit. It was Winzen Research that pioneered the use of polyethylene resin for plastic balloons that were opening doors for high altitude research at Holloman.
The first polyethylene balloon had been launched at Holloman on July 3, 1947, twenty days before the first missiles took to the skies over the military base. The years that followed saw balloons carry cosmic ray track plates to altitude to measure radiation. There were also flights using mice to determine the effects of cosmic radiation on living beings. The mice flights presented an interesting challenge for Simons, namely how to keep his animals alive in a pressurized capsule for longer flights than the Alberts’ on V-2 Blossoms. Using the mouse as a yardstick, he developed a system wherein one “mouse unit” was the amount of heat produced by a mouse. From there, he could scale up his capsule designs for other payloads, for a menagerie of small animals rather than a large number of mice.
One day, Stapp walked into Simons’s office wondering how many mouse units a man produced and whether it would be possible to launch a human in a scale-up version of his animal capsules. Simons thought over the question and did some basic calculations. The idea didn’t immediately raise red flags for Simons. A five-hundred-mouse unit capsule should be able to carry a man into the upper atmosphere, he told Stapp, and keep him aloft long enough to gather data about the environment. Both men agreed that a human flight would not only be useful for biomedical research but necessary. Animal passengers couldn’t do anything but breathe, and, if the mood struck them, also eat, urinate, and defecate during a high-altitude flight. Only a human could describe the experience, run tests, and serve as a subject for research into the psychological aspects of high-altitude flight and shed light on the thoughts and feelings future space travelers might have to leaving the Earth. It was an invaluable data set Stapp and Simons knew they couldn’t get any other way. Besides, there was an increasing need not only to understand the upper atmospheric environment but to develop the capsules and self-contained pressurized environments that pilots would need in high altitude aircraft and space travelers would need outside the atmosphere. For the moment, a manned balloon flight was the best way to simulate the space environment in a controlled and sustained manner.
Breaking the Chains of Gravity Page 18