The Army Air Force’s idea of what this high speed research aircraft should look like differed from what Stack had initially imagined. The most notable difference was the proposed power plant. While Stack wanted the research aircraft to be jet powered, Kotcher was sure the only way to break the sound barrier was to swap the jet engine for a rocket engine. In 1943 he had worked as a project officer on the proposed Northrop XP-79 rocket-propelled interceptor. During his tenure with the program he had learned that the U.S. Army knew that the German Luftwaffe was developing a rocket-propelled interceptor as well, the Messerschmitt ME-163. With contemporary turbojet engines unable to push an aircraft faster than sound, using a rocket engine like the Germans was an obvious solution. The Army Air Force ultimately agreed with Kotcher, and the military specifications for the research plane emerged quite different from the NACA’s initial design.
The Army Air Force wanted to launch the rocket-powered plane from underneath a high-altitude bomber to conserve its fuel for the short but explosive powered flight, and it didn’t want to take a measured approach. The AAF wanted to make its assault on the sound barrier early in the test program. Because the military was footing the bill, naysayers against a piloted research vehicle didn’t carry much weight. The aircraft was given the name XS-1 for Experimental Supersonic, which was eventually shortened to X-1. Its rocket engine would be built by Reaction Motors, the same company building the engine for the Army Air Force’s Project MX-774 missile.
With the basic design of the X-1 set by the Army Air Force, it fell to Bell Aircraft to figure out the specifics of the aircraft. For inspiration, engineers looked to a .50 caliber bullet, which they knew left the barrel of a gun at supersonic speeds and flew stably to its target. If a bullet could break the sound barrier in level flight, a bullet-shaped aircraft would be able to as well. The NACA stepped in to help fill gaps in Bell Aircraft’s research left by missing wind tunnel data. NACA engineers ran drop-body tests wherein winged, bomb-like missiles were released from a B-29 bomber at thirty thousand feet in a rough replication of the X-1’s air launch profile. The data was limited but was enough to help inform the design of a supersonic aircraft. Another stopgap test method the NACA brought to the X-1 program was the wing-flow method pioneered by Robert R. Gilruth, chief of the Flight Research Section. He figured that by mounting a model airplane perpendicular to and at the right location above the wing of a P-51D, the air flowing over the wing would be supersonic in a dive. It was far less precise than a wind tunnel, but it nevertheless gathered high speed flow data. The NACA also ran rocket-model tests wherein models were mounted on rockets that were then fired from the launch facility at Wallops Island on the coast of Virginia. The data from all these tests combined with the existing core of compressibility data the NACA had obtained over the previous twenty years became the basis of the scientific and engineering material Bell Aircraft used to design the X-1, breaking from the Army Air Force’s blueprint where necessary.
It was exactly this type of creative aerodynamic problem solving and flight data monitoring that the NACA was known for. Created to improve America’s offensive air power, the agency was originally led by a committee of twelve volunteers representing government, military, and industry acting in an advisory capacity reporting directly to the president. Initially tasked with coordinating existing aviation programs, the NACA soon grew large enough that it needed its own research centers. The first had been the Langley Memorial Laboratory, established in Virginia in 1917 and formally dedicated three years later with a ceremony that included an aerial display with a twenty-five-plane formation. The center quickly gained a reputation for finding practical solutions to difficult aeronautical problems, a reputation that spread. Management never had to recruit the best minds in the field; the best minds came to Langley on their own and the workforce expanded rapidly.
By 1925, there were more than one hundred employees working at the Langley Laboratory. Part of what made the site so successful was its facilities, which included some of the best wind tunnels in the world, including a pressurized, or variable density, tunnel. Unlike traditional open wind tunnels, this closed tunnel pioneered the use of compressed air to replicate different atmospheric environments. Running parallel to the early successful tests with the wind tunnels were Langley’s full-scale flight test programs. These helped set enduring guidelines and promoted a deeper understanding of the instrumentation needed for acquiring accurate data that could then be correlated with wind tunnel data.
The X-1 made its first ten unpowered gliding flights at the Pinecastle Army Air Field just south of Orlando, Florida, in the first months of 1945. These flights were designed to test the aircraft’s airworthiness, handling characteristics, and the process by which it would be air launched, all without firing the rocket engine. Bell Aircraft pilot P. V. “Jack” Woolams flew the plane on behalf of its manufacturer while a small NACA team led by Walter C. Williams collected and analyzed the flight data. With these tests complete, the aircraft was unveiled to the public during an open-house exhibition at Wright Field on May 17, 1946. Painted bright orange so it could be seen in the sky and strongly reminiscent of a bullet, the streamlined plane looked every bit the exotic and futuristic aircraft that could break the sound barrier. Just thirty-one feet long, the X-1 was compact with a small, barebones cockpit toward its nose. Straight, stubby wings jutted out from the sides of its fuselage, which housed two propellant tanks, twelve nitrogen spheres, three regulators for pressurization, and retractable landing gear. Though it housed a state-of-the-art rocket engine, the X-1’s complexity was kept to a minimum to eliminate as many variables from its already demanding flight plan.
The second production X-1 was the first to be fitted with a rocket engine in September 1946. It was around this time that operations for the program moved to Muroc; both Army Air Force personnel and a small ground crew from the NACA with Williams in the lead moved to the desert site in anticipation of the first rocket-powered flights.
On December 9, twenty-three-year-old test pilot Chalmers “Slick” Goodlin was nestled in the cockpit of the rocket plane as the B-29 mother ship took off from the Rogers dry lake bed. A former Royal Canadian Air Force and U.S. Navy test pilot, Goodlin had left the service and joined Bell Aircraft as a civilian research pilot in December 1943. He was rumored to be making a small fortune flying the experimental aircraft, and Bell was touting him as a hero, the inevitable first man to break through the sound barrier. Goodlin was among a new breed of pilots that emerged alongside experimental aircraft in the wake of the Second World War. It wasn’t enough for a pilot to fly a new type of aircraft, not when there were engineers needing data from each flight. These new aircraft demanded test pilots, men who combined the skill of a flying ace with the fearlessness to fly through dangerous and unknown environments without sacrificing the engineering goals of the flight.
That December morning, at twenty-seven thousand feet, the orange plane fell away and quickly lost altitude before the rocket engine kicked in, propelling the aircraft forward as flame exploded from its tail end. Goodlin was forced backward in his seat as he watched the B-29 falling away behind him. Inside the cockpit, the rocket engine’s roar was incredibly quiet. He gingerly tested the controls and paid attention to exactly how the X-1 handled under rocket power. Aware of the immense engine firing behind his seat, he maneuvered his controls with the gentle precision of a surgeon, hitting a top speed of 550 miles per hour before running out of fuel. Now without power, he skillfully brought the X-1 to a gliding landing on the lake bed at Muroc. He came down from that flight knowing what the airplane could do. He was sure it could fly a thousand miles an hour, and was sure that he would be the one to make that flight.
But Bell’s public celebration of Goodlin proved premature when the pilot began disputing his fee. Goodlin’s original contract with Bell stipulated that he take the X-1 up to Mach 0.8 as phase one of the program. He’d completed this goal. But for phase two, the phase that would see Goodlin push be
yond Mach 1, he wanted additional financial compensation in light of the risk he was taking. In renegotiating his contract Goodlin asked for a bonus of $150,000 paid over five years to avoid high taxes. Bell Aircraft’s lawyers rejected Goodlin’s proposal, and the pilot refused to fly until the issue was resolved.
Fed up with the delays this stalemate over Goodlin’s contract was causing, the Army Air Force decided to take over the X-1 program earlier than expected in June of 1947, the same month Goodlin’s contract with Bell was canceled. By then, the two airplanes together had made twenty-three powered flights and fourteen glide flights, demonstrating its structural integrity to a top speed of Mach 0.82. The rocket engine had been finicky, but overall proved itself as safe and reliable. The hitch with the X-1’s takeover by the Army Air Force was that the plane was suddenly without a pilot.
One afternoon in May before the aircraft’s transfer was finalized, all the fighter pilots at Wright Field were called in to a meeting and asked who among them would be willing to fly the experimental rocket plane. Among the eight or so volunteers was Captain Chuck Yeager, who hadn’t heard various flight test engineers refer to the X-1 as a death trap owing to the unknowns of supersonic flight. A few days later, Colonel Albert Boyd called Yeager into his office. Boyd, chief of the Flight Test Division, asked the young pilot why he’d volunteered to fly the experimental aircraft. Yeager responded honestly that it sounded like an interesting program, something interesting to fly. Boyd impressed upon the young pilot that the X-1 wasn’t just an airplane, it was the airplane that would change aviation. There were airplanes on the drawing board that would fly five times the speed of sound, airplanes that would take pilots into space, and they all hinged on the X-1 breaking the sound barrier.
Though he was one of the most junior fliers at Wright Field, Boyd considered Yeager to be the most naturally instinctive pilot he had ever seen, a pilot who could fly with extreme precision without sacrificing rock-solid stability in the air. Flying the X-1 supersonically would demand these traits, and not only did Yeager have them all in spades, he also had the right personality to remain extraordinarily calm and focused when faced with a stressful situation. In June, Yeager went to Bell Aircraft’s facilities to check out the X-1 in person. He crawled around the cockpit and was invited to fire the rocket engine while it was safely held to the ground. The sound accompanying the burst of flame that shot twenty feet from the tail end of the aircraft was so shocking and loud Yeager covered his ears with his hands. It was incredible. He wanted to fly the rocket plane, and Colonel Boyd told Yeager it was his.
Before Yeager’s selection as the X-1’s new pilot was made public, news that Goodlin would not fly the X-1 supersonically had trickled through the aviation industry and into the academic sphere. It reached Scott Crossfield, a young pilot turned engineer who was pursuing his bachelor’s degree in aeronautical engineering at the University of Washington. He wrote a letter to Bell Aircraft to volunteer to fly the research airplane through the sound barrier himself, highlighting his relevant career experience. He was a licensed private pilot and graduate of a civilian aviation school who had withdrawn from university to work for the Boeing Aircraft Company before joining the Army Air Force. He had then returned to Boeing briefly before joining the navy as an aviator. After finishing his flight training, he had served as a fighter and gunnery instructor and maintenance officer before spending six months overseas during the Second World War during which he never saw combat. Home from the war, he had returned to university under the G.I. Bill and joined a naval air reserve unit at Sand Point Naval Air Station, maintaining his proficiency by flying fighter aircraft on weekends. Though Crossfield was just twenty-six, his résumé spoke to his readiness to take on a new challenge like flying a rocket-powered aircraft.
If Crossfield’s letter reached Bell Aircraft, it fell on deaf ears and likely landed in a wastepaper basket. Not long after he mailed his appeal, Crossfield read in the newspaper that Yeager would be replacing Goodlin. That he wouldn’t have a chance to fly the X-1 didn’t dissuade Crossfield. Instead, it strengthened his resolve. He threw his energies into his studies, progressing directly into a master’s degree program after finishing his bachelor’s, all the while maintaining his unwavering passion for flying. He was sure that his time in the aviation world was yet to come.
The X-1 was just the beginning of a shift in the landscape of aviation. The NACA was changing, too. In September, while Yeager was preparing for his assault on the sound barrier, Hugh Dryden resigned from the Bureau of Standards to take on the role of Director of Aeronautical Research at the NACA. Under the direction of a man who had spent a career investigating phenomena on the cutting edge of aviation, the new leadership promised changes. It was that month that the air force became a separate service branch as well.
An hour before sunrise on Tuesday, October 14, 1947, Muroc Air Force Base was buzzing with activity. Technicians were busily readying the X-1 for a powered flight, fueling the orange aircraft with ethyl alcohol cut with water and liquid oxygen before carefully installing it in the bomb bay of a B-29 bomber. When the Sun finally rose four minutes before seven, the day was revealed as bright and clear with only the occasional scattered clouds. After hours of preparation, the bomber finally took off at ten o’clock into welcoming skies.
Painted on the X-1’s side that morning were the words Glamorous Glennis in honor of Yeager’s wife, who had not been happy when she dropped him off at Muroc that morning. Yeager had been thrown from a horse a couple of days earlier and refused to see a doctor about the two ribs he’d broken; he wasn’t going to let anything keep him from flying the X-1. By this time, he had flown eight powered flights in the rocket aircraft and knew its quirks. It was designed to withstand three times the stress Yeager could, and the only way to prove it could fly supersonically was to fly it supersonically. Yeager was getting tired of these incremental flights approaching Mach 1. If the flight that morning went off without a hitch, he privately promised, he would push the airplane through the sound barrier on the very next run whether the air force thought he was ready or not.
Once the bomber was airborne, Yeager gingerly climbed down the ladder from the mother ship, settled himself in the X-1’s cockpit, and closed the hatch with the help of a sawed-off broomstick handle Captain Jack Ridley, the B-29’s pilot that morning, had left for him. Only Ridley knew about Yeager’s broken ribs. He’d left the broomstick to give Yeager enough leverage to close the hatch without hurting his injured side. Just before ten-thirty, twenty-thousand feet in the air, the X-1 fell away from the B-29. Yeager dropped five hundred feet before getting the aircraft into a nose-down orientation, but once he did he lit the four barrels of his rocket engine in rapid sequence. A trailing exhaust jet of shock diamonds appeared behind the aircraft as it accelerated to Mach 0.88 and began to climb. Now in the little understood transonic realm, Yeager shut down two of his rocket barrels and tested the aircraft’s controls as the Mach meter showed the X-1 was still accelerating. Invisible shock waves buffeted over the wings as the aircraft reached forty thousand feet and Yeager relit one of his rocket barrels. Still monitoring his instruments, Yeager watched in shock as the needle on the Mach meter moved smoothly from 0.98 to 1.02 before jumping to 1.06. Yeager was flying supersonically and he hadn’t felt a thing. He called to Ridley in the B-29 that his Mach meter must be screwy because he’d apparently gone right through the sound barrier without his ears or anything else falling off.
It had been exactly as the engineers predicted. The sound barrier wasn’t a wall to break through, it was an engineering challenge, and the expertly designed X-1 was stable after passing through the transonic range without serious problems. For Yeager, finally going supersonic after all the anticipation and worry was a bit of a letdown, but the implications for aviation were significant. The flight marked the beginning of a new phase in aviation and the beginning of a split in Muroc’s personality. Evaluation flights of new aircraft would always have a place at the desert outpo
st, but now experimental aircraft would be flying alongside them.
CHAPTER SEVEN
A New War, a New Missile, and a New Leader
In December 1949, Muroc Air Force Base was named Edwards Air Force Base in honor of Captain Glen Edwards who was killed flying a prototype Northrop YB-49 Flying Wing. Predominantly owned and run by the air force, the NACA did retain a presence. In November 1949, the organization had set up a site there called the Muroc Flight Test Unit. The nearly one hundred employees fell under the direction of Walt Williams, chief of the station. The NACA, too, had a new leader in Hugh Dryden, the organization’s first ever director. As its senior full-time officer, Dryden managed from headquarters in Washington the activities of the Langley, Lewis, and Ames laboratories, as well as the new Muroc Flight Test Unit that operated under Langley’s direction. And as he had done each time he had been promoted within the Bureau of Standards, Dryden used his position to shift the NACA’s research efforts toward his own interest in supersonic and hypersonic flight.
As the NACA began a shift toward increased supersonic flight research, Scott Crossfield was completing his master’s degree and researching various career paths. Being a research test pilot was his dream career, and the NACA’s Ames Laboratory in California was his dream employer. Established in 1939 as the NACA’s second field site, Ames was known for its sophisticated wind tunnels, research aircraft, and the academic approach to theoretical aerodynamics its engineers and scientists applied to the leading aeronautical problems of the day. Ames, more than any other NACA site, was ensconced in the academic tradition Crossfield was comfortable with, and its activities appealed to his own academic interests in the field. He submitted his application but the reply came back with an order for him to report to the Muroc Test Flight Unit at Edwards Air Force Base instead. Crossfield was disappointed. This smallest NACA center had just two small research pilot groups with two or three pilots apiece and a handful of engineers, and he knew the base was primarily an air force site, not a research site.
Breaking the Chains of Gravity Page 12