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"Faster Than Sound"

PBS Airdate: October 14, 1997
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ANNOUNCER: Tonight on NOVA, great machines.

DE BEELER: Well, there are a lot of people that said it was impossible. And that's why they talked about the sonic wall. That means like a brick wall.

ANNOUNCER: Even greater heros...

CAPT. ROBERT S. JOHNSON: It was an uncontrollable situation once you hit that certain speed.

ANNOUNCER: ...who risked it all to make aviation history.

BRIG. GEN. CHUCK YEAGER: It was a very important secret and it paid off.

ANNOUNCER: Now, get the real story behind the race to fly Faster Than Sound.

Major funding for NOVA is provided by the Park Foundation. Dedicated to education and quality television.

... by the Corporation for Public Broadcasting, and viewers like you.

SIR PETER MASEFIELD: There was a feeling that this was a barrier. It couldn't be overcome, because airplanes would go out of control and nothing could be done to bring them in.

DE BEELER: Well, there were a lot of people that said it was impossible. And that's why they talked about the sonic wall. That means like a brick wall. And a lot of people accepted that.

STACY KEACH (NARRATOR): The day that a plane first flew faster than sound was a milestone in the history of aviation. Many thought it couldn't be done. But great risks were taken, and lives were lost to prove the skeptics wrong.

CAPT. ERIC BROWN: There was a huge amount of vibration juddering through the aircraft. As you got closer to the speed of sound, each bite beyond a certain limit was fraught with the possibility of disaster.

STACY KEACH (NARRATOR): In the quest the break the sound barrier, Britain came up with this bullet-shaped design. But the aircraft was mysteriously canceled before it ever got off the ground. It was the United States that would be first. And the key to its success was a closely guarded secret.

BRIG. GEN. CHUCK YEAGER: It took the rest of the world five years to find out how we flew above the speed of sound. Had we blabbed our mouth, you know, they'd have known it at that time.

STACY KEACH (NARRATOR): It was during World War II that pilots first experienced the problem of flying too close to the speed of sound. It happened when fighter planes went into steep attacking dives. Some went so fast they were buffeted by forces they could not control. This occurred as planes approached the speed of sound itself: 760 miles an hour at sea level. John Golley, a British pilot, accidentally flew into trouble during a raid over occupied France.

JOHN GOLLEY: Well, I was flying the Typhoon, which was really a seven ton brute. It was a big, big chap, three times the size of a Spitfire, twice the size of a Hurricane. It was physically hard to handle when you threw it around, but it was fast. We had no indication that we might be approaching the speed of sound. Well, definitely, we had no idea. None whatsoever. Now, I found that first dive that I did was fairly horrific. The speed built up enormously. We were going way over 500 miles an hour, and one had tremendous vibration. It was frightening in the sense that one was fighting to control the aircraft, and one's hands were on the spade grip of the control column, which was getting stiffer and stiffer. All we knew was that we had to get the bloody things out of the dive, to survive, and it took a lot of effort.

STACY KEACH (NARRATOR): No one knew what happened to planes as they approached the speed of sound. For some reason, they began to behave unpredictably. Pilots began to speak of an impenetrable wall to high speed flight, a sound barrier. No official records were kept, but some wartime pilots simply disappeared during high speed dives.

JOHN GOLLEY: Guys were missing, and we didn't know. We didn't know what happened to them, whatever. Their controls could have locked up for some reason or another, which we never knew. We never discussed it. All we knew was that if a guy didn't come back, he'd had it.

STACY KEACH (NARRATOR): American pilots faced similar problems. Twenty-eight German planes were shot down by flying ace Robert Johnson. But he nearly died when his Thunderbolt flew too close to the speed of sound.

CAPT. ROBERT S. JOHNSON: Well, it looked a little bit like an elephant going into combat, compared to the Spitfires and those type airplanes. But it was very—It was the fastest prop driven airplane that we had. I was like everybody else. I was wanting to see how fast I could go.

STACY KEACH (NARRATOR): Johnson took the plane up to about 30,000 feet, and turned it into a steep dive.

CAPT. ROBERT S. JOHNSON: My nose, which I thought was straight down, suddenly tucked under. And my controls locked, and you could not budge the controls, no matter how hard you wanted to. And believe me, your mind was going like this—What to do, what to do, what to do? Well, you were so frightened that you tried everything, and of course, then, at the bottom of the dive, as it pulled out, you'd black out, so you didn't come to until you're back up to about 19,000 feet.

STACY KEACH (NARRATOR): Johnson was lucky. His controls began to work again when dense air slowed the plane down as it descended. One of the few women test pilots in the 40's also accidentally flew too close to the sound barrier. Ann Carl was doing some aerobatic flying in a Thunderbolt when she dived into danger.

ANN B. CARL: Funny things began to happen inside the cockpit. Dust was flying around. The stick would bang over against my leg, and I tried various things. It was certainly not a pleasant feeling to have the plane out of control. We were just going so fast that I didn't think I could probably get out.

STACY KEACH (NARRATOR): Like Johnson, Carl also regained control of her plane just in time.

ANN B. CARL: As we were coming out of the dive, I wondered why I was saved, as a matter of fact. I thought it was an experience that I would certainly not forget.

STACY KEACH (NARRATOR): But some pilots who flew too near the barrier didn't survive.

CAPT. ROBERT S. JOHNSON: I was just standing out there watching, waiting to take off, and I saw these two airplanes just come screaming down, straight down. And there wasn't much else to watch, except they went in, into the water. We didn't know what had happened. We assumed that they just plain old dived in. And they did plain old dive in. But we didn't know that they could not get out of it. It was an uncontrollable situation once you hit that certain speed.

STACY KEACH (NARRATOR): It was the threat of Germany's rapid advances in aviation that finally inspired both America and Britain to look further into the problems of high speed flight. In 1942, a German fighter plane, the Focke Wulf 190, became known to the Allied Forces. Its speed and maneuverability were an unwelcome surprise.

SIR PETER MASEFIELD: The Focke Wulf 190 certainly provided an additional spur to the British designers and test flyers to get the edge on the 190. But we were on the edge all the time, of having to push, push, push to get that little bit of extra which would make the difference between life and death in some of these dog fights and fighter sweeps which were going on at the time. But this was a very difficult period, because we were approaching the speed of sound. And airplanes were becoming uncontrollable, because it wasn't realized what the problem was. This was something quite new. The so-called sound barrier was beginning to be approached.

STACY KEACH (NARRATOR): In the 1940s, wind tunnels were of little value in the effort to understand why pilots were losing control. At the critical speeds just above and below the speed of sound, shock waves in the tunnel would choke off the airflow around the model.

SIR PETER MASEFIELD: The problems of trying to face up to the control difficulties as we approached the speed of sound, was that we couldn't reproduce these in wind tunnels. No wind tunnel could give us the speed of flow over a model airplane, which would reproduce what we were experiencing in the real airplane going at close to the speed of sound. So, the only way to approach this was in full scale testing of actual airplanes flying at actual speeds.

STACY KEACH (NARRATOR): In Britain, a select group of pilots was asked to risk their lives to get the answers. One of them was Eric Brown, a member of a government high speed test unit. His assignment was to deliberately fly a Spitfire into this dangerous region.

CAPT. ERIC BROWN: Of course, when you're young and you're in a job like a research test pilot, you are very keen to try and beat this so-called barrier. There is always that feeling you have—a ridiculous feeling the young will have—of immortality. And I think this is what allows you to press on.

STACY KEACH (NARRATOR): The plan was to approach the sound barrier in stages, to minimize the chance of disaster. But it meant flying a plane faster than it had ever been done before.

CAPT. ERIC BROWN: I took the aircraft up to a high altitude of the order of 40,000 feet. There, we would have a flat-out run at full throttle for about five minutes to build up the maximum steady speed we could. I pushed the aircraft over into a dive off the order of 30 to 40 degrees. At that particular angle, you could begin to feel a huge amount of vibration juddering through the aircraft, a lot of noise around the cockpit.

STACY KEACH (NARRATOR): Most frightening of all, it became harder and harder to pull the Spitfire out of its dive. The elevator, the movable part of the tail that changes the angle of the dive, wouldn't work, no matter how hard the pilot pulled back on the control stick.

CAPT. ERIC BROWN: I was certainly of the opinion that I was getting to my limit. There is always the risk that your muscles will not hold out in this situation, and you will relax your grip on the stick. And then, that will allow the aircraft, of course, to go steeper and steeper, with the end result probably fatal.

STACY KEACH (NARRATOR): Another member of the team, Tony Martindale, barely survived a crash. The engine on his Spitfire exploded as he approached the speed of sound. Its propeller came off. He escaped with a broken back. Others weren't so lucky. Four of the six test pilots from the high speed unit died at Farnborough doing these tests.

SIR PETER MASEFIELD: Yes, test pilots had always a difficult time, but at no time more difficult than when they were being sent up to try and approach the speed of sound with under control responses from airplanes. Baling out at those sort of speeds—There weren't ejector seats in those days—into nearly a 500-mile-an-hour slipstream was a thing which was only just survivable, and in many cases not survivable. Several test pilots, sadly, were lost because the airplane went uncontrollable.

CAPT. ERIC BROWN: Very early on, we had a young Canadian pilot, and he was sent to us in the high speed unit, and he was in a dive, and he must have let things go a little too far. And it steepened all the way, and he went straight into the ground at very high speed indeed.

STACY KEACH (NARRATOR): But the risks and sacrifice helped reveal why these World War II fighter planes were going out of control. At slow speeds, the air flowed smoothly over the thick wings. But near the speed of sound, air traveled so fast that it formed shock waves, causing it to break away from the wing surface. The air would become turbulent, disrupting the wing and tail controls. Worse still, the lift generated by the air moved backwards, tipping the plane into an uncontrollable dive.

SIR PETER MASEFIELD: What was happening, the central pressure on the wing was changing, and firstly lateral control, the sideways tilt of the airplane was going beyond anything that could be coped with. The nose would drop, speed would increase, and then a sudden pitch up would occur as the breakaway of the air flow over the wings took place. And all this was new, so we were really in a difficult era at that time.

STACY KEACH (NARRATOR): By flying planes with different wing thicknesses, it was discovered that the thinner the wing, the less the air flowing over the top is speeded up. This prevents it from breaking away from the wing surface, allowing the controls to keep the plane in level flight.

CAPT. ERIC BROWN: Well, we were learning quite a lot about the wings of the aircraft. We realized that thinness was essential if you were going to really get high speeds. So, there were structural problems for the designers.

STACY KEACH (NARRATOR): A second lesson was learned as well. The sound barrier could not be broken in the propellerdriven plane. At very high speeds, shock waves also begin to form on the spinning propeller blades. So, the faster it goes, the less efficient the propeller becomes.

CAPT. ERIC BROWN: Fundamentally, the drag of the propeller was so high that it would never allow the aircraft to attain those speeds without running into virtually a brick wall. And we just had to wait until something better came along.

STACY KEACH (NARRATOR): By the early 1940s, there was a promising new engine in development. It had been invented by Frank Whittle, an officer in the British Royal Airforce. Whittle's invention was simple but revolutionary, with few moving parts, a spinning turbine and compressor that fed air to fuel burners. It was the jet engine.

SIR PETER MASEFIELD: The way that the jet was able to outpace, and eventually surpass and replace the piston engine was that it could be developed with fairly unsophisticated fuels like paraffin, kerosine, to give much greater powers and much greater thrust to push airplanes forward that could be achieved through the rather primitive thing of a large, whirring propeller. What the jet engine did was provide a simple solution to how to push the airplane forward by squirting a jet out of the back, faster than the speed of sound, and therefore, the airplane had to respond by going faster than the speed of sound itself.

STACY KEACH (NARRATOR): But the performance of Whittle's early designs was far from supersonic. Invented in 1929, the engine was hard to build, and required new heat-resistant metals. The British government thought the difficulties were insurmountable, and ignored Whittle for eight years. Germany took the lead in jet technology, flying the world's first jet powered plane in August, 1939. Called the HE 178, it was the brainchild of Ernst Heinkel, a forward-thinking aircraft manufacturer. He made use of the talents of a young engineer, Hans von Ohain, who invented the jet that powered the 178.

HANS von OHAIN: The 178 was not built really for very high speed. It was an experimental aircraft. Heinkel envisioned from the success of the 178 to go to a next airplane which is much faster and possibly go beyond the speed of sound. He said to all of us, "This is the beginning of a new time of higher and higher speed." That is what he said.

STACY KEACH (NARRATOR): By 1942, Germany possessed aircraft that could fly nearer to the speed of sound than those of any other country. One of them, the Messerschmitt 262, a jet fighter, could travel at 540 miles an hour. Some wrongly claimed it had broken the sound barrier. Heinrich Beauvais was a German test pilot who flew the plane many times.

HEINRICH BEAUVAIS: One pilot, a man called Mutke, thought he had passed the speed of sound. But the plane had problems at high speed. It was damaged by buffeting. The rivets popped out and the skin on the fuselage buckled. So, I don't believe it, and neither did the experts.

STACY KEACH (NARRATOR): The 262's airframe and engines were never designed for supersonic flight. But its mere existence, and that of other advanced German aircraft, helped spark the race to build a plane that could fly faster than sound. The first comprehensive evidence of the German lead in high speed jets came in a top secret intelligence report delivered to the British prime minister in 1943. At the time, Britain only had one functional jet plane in the air—an experimental aircraft. The classified briefing contained reconnaissance photos of German airfields that showed just how far the allies were lagging behind.

SIR PETER MASEFIELD: The things one could see were scorch marks on grass airfields, and this gave evidence of jet engines before we knew anything more about them. And what were we doing about it? And we were doing jolly little, in fact, apart from desultory help to Whittle. So, there's no doubt that these intelligence reports did spur on the air ministry to produce really fast jet airplanes which could possibly, if the war went on significantly further, have an influence in the actual front-line battles.

STACY KEACH (NARRATOR): There was a second spur as well. A British agent's report of a German plan for a supersonic jet. It was only a design study, but Germany's technological know-how had to be taken seriously.

SIR PETER MASEFIELD: It was thought that it was about time we looked to see whether we should go towards flying faster than the speed of sound—a new concept altogether—although there had been, even before the war, thoughts that one day we might be going faster than sound. But how it would be done, nobody had the foggiest idea.

STACY KEACH (NARRATOR): In 1943, the British government asked a small plane manufacturer called Miles Aircraft to design and construct the world's first supersonic plane. Miles built training planes—not high speed aircraft. But the company had a reputation for innovative design. The engineers faced a daunting task: to build a plane capable of flying at 1,000 miles an hour—almost twice as fast as any aircraft had ever flown before.

DENNIS BANCROFT: We were a little bit shaken, of course, because up till that time, we had thought that the speed of sound was something in the distance which we couldn't approach. I mean, we would make airplanes go faster and faster, but the speed of sound was so far ahead we just couldn't get through the solid barrier. The ministry required us to make the airplane and get it flying at 1,000 miles an hour in nine months, which even at that time we thought was a bit much. But of course we thought we could do it. We'd make anything fly.

STACY KEACH (NARRATOR): What they came up with was the M-52: a totally new concept in aircraft design.

DENNIS BANCROFT: The only object that we have information on going faster than speed of sound—That was bullets, so that we went for the information on bullets and used that information for the fuselage. The thinner the wing, the faster it will go. So, you had to have a very thin wing. So anyway, we chose a thin wing and then had to test it.

STACY KEACH (NARRATOR): Much of the testing and construction of Britain's supersonic plane was recorded by a Miles Aircraft camera team. The footage has not been shown before.

DENNIS BANCROFT: The wing was put onto an ordinary 200 horse power Miles Aircraft, and it was flown, and it behaved very well. But we were quite confident that the tests we did would work, because we checked them as we went along the line.

STACY KEACH (NARRATOR): Just two months after the British team began work, the United States entered the race to break the sound barrier. The decision was made at a wartime gathering of some of the country's top aviation experts. They were worried about America falling behind Nazi Germany. The country did have a new jet fighter, and those present watched a film of the plane being put through its paces. The XP-59A, as it was called, relied on the Whittle jet engine, a gift from the British. But despite its jet power, the XP-59 did not perform any better than propeller-driven planes.

ANN B. CARL: The P-59A didn't go through the speed of sound quite, but it did go faster than present fighters, a little bit. And so, the feeling was in the Air Force that this was a step ahead. But there were many steps still to go.

STACY KEACH (NARRATOR): What the country needed, it was decided, was its own supersonic plane. The United States had been exploring the feasibility of high speed flight for more than a decade. But it was clear that unless its research efforts were stepped up, the country would fall seriously behind. So, the Bell Aircraft Corporation, as it was called in the 1940s, was enlisted to build America's first supersonic plane. Its founder, Larry Bell, had a reputation for getting things done fast and on budget. But outside Bell, many doubted his chance of success.

DE BEELER: There were considerable bouts of pessimism. That was the environment at that present time. And this fed down to the designers even, themselves—"How strong do I have to build the airplane? What do I have to build the airplane to accommodate?" And these were unknowns and big questions at that time. Well, there were a lot of people that said it was impossible. And that's when they talked about the sonic wall. The sonic wall, that means like a brick wall. And a lot of people accepted that. My personal feeling is that, let's go step by step and use all the tools and knowledge in Europe, anywhere we could find it, and put it together and see what we would come up with.

STACY KEACH (NARRATOR): It is unclear just how much information was exchanged between the British and American teams. But for some across the Atlantic, the memory of the collaboration remains a bitter one.

DENNIS BANCROFT: The idea was that they had decided that it was a good idea to make a supersonic airplane, and they had heard that we were making one. So, they came over to England with the idea that they would have all the information that we had accumulated, the idea being that a fortnight later, we would go to America and they would give us all the information the Americans had got. But after the Americans had got the information, take the drawings away within a fortnight. When we were trying to arrange the visit, they just said, "Sorry. Secrecy. The Pentagon says you can't."

STACY KEACH (NARRATOR): But the real threat was Germany. If America was months behind the British, it was even further behind the Germans. By 1944, Germany already had a vehicle that could travel faster than sound: the V2 rocket, a weapon of terror unprecedented in modern warfare.

SIR PETER MASEFIELD: Because it was supersonic, the V2 arrived before you heard it coming. You heard it coming after it had gone off—bang!—on the ground. And it was pretty disturbing to the populace. The Germans had what in effect was interplanetary missiles when nothing else had been thought in that line before.

STACY KEACH (NARRATOR): And a missile like the V2 was aerodynamically much simpler than a supersonic aircraft. By early 1945, the Miles engineers in Britain were constructing a full scale mock-up of their plane. They were confident it would work. But they did have plans to cope with a disaster.

DENNIS BANCROFT: The cockpit was held on by four or five metal bars. Those had explosive charges around them, and if he had to get out, he would explode those, and the whole cockpit would leave the airplane, and then he would be in a capsule which would be completely safe. It was really a modern ejector seat, so we were doing what they are now doing 50 years ago.

CAPT. ERIC BROWN: The cockpit was exceptionally small. Therefore, the pilot had to be of small stature. You were almost supine in the aircraft. And the nose wheel, when it retracted, was lying straight between the pilot's legs. So, it was going to be somebody pretty well with my stature. I am of the order of five feet seven, and you couldn't really get anybody bigger in there.

DENNIS BANCROFT: The pilots themselves, they thought it was a jolly fine idea. They all wanted to have a go. Oh yes, they thought it was absolutely an excellent idea to have a go. There was no suggestion that it was an unfair risk in any context at all.

STACY KEACH (NARRATOR): By the end of the war, no country had built a plane that could fly faster than sound. But the Germans had come fairly close. Just how close they came became clear when the Allies got their hands on the Messerschmitt 163, a rocket-powered plane. It flew to the very edge of the sound barrier, but its wings were not suitable for supersonic flight.

SIR PETER MASEFIELD: The ME 163 was the first really genuine flying rocket airplane with an endurance of only about ten minutes of flight at full power but getting on for the speed of sound about 90% up towards it, and pretty formidable, but also killed a lot of its very brave test pilots. It was dangerous because firstly, it was going faster than anyone had encountered before, and therefore going out of control on occasion. And secondly, because these rocket fuels blew up, and blew everything to smithereens.

STACY KEACH (NARRATOR): And there were other dangers to high speed flight. The bell engineers were worried about the stresses the plane would encounter. So, they designed it to withstand loads up to 18 times the force of gravity, far beyond what was needed. Equally problematic was the choice of engines. Rocket motors were prone to explosions, but they could deliver enormous thrust. Others believed the more reliable jet engine was the answer. But jets of the day lacked the power to reach supersonic speed, except in steep and risky dives. After much debate, it was the rocket engine that finally won U.S. approval. But the choice was not without controversy.

DE BEELER: Personally, I had some reservations about a rocket, when you see them operate, because it's like a small explosion. But it would get you to the area of interest a heck of a lot quicker, and I'm not sure that we knew that much about a jet engine, the time to get there, and all the aerodynamic problems of getting the air to the engine. The rocket appeared to be the simplest.

STACY KEACH (NARRATOR): Britain had a good reason for not following the American lead.

DENNIS BANCROFT: Whittle had made a special engine, being six or seven times the thrust of any propeller-driven or jet engine at that time, and with such a tremendous increase in power, the sky was the limit. But we were expecting to fly at about six months time into that stage, and for the test flights.

STACY KEACH (NARRATOR): But early in 1946, Miles Aircraft received a letter from the Ministry of Aircraft Production canceling the project.

DENNIS BANCROFT: We were all extremely surprised. All the problems almost, we thought, were over. We got a sound airplane, and everybody agreed it was going to be a success. So, when you've got a success, such an advance compared with anybody else in the world, and you just get a memo, "Please stop," one is shaken, to say the least of it. If somebody had given us a reasonable reason for this cancellation, we wouldn't have been—You know, we wouldn't have been too worried. We'd just accept it. But not giving a reason for it, just cutting out a successful—It's like sort of getting an airplane onto the airfield, ready for test flight, and then somebody saying, "Oh, don't bother. Throw it away." It's—I mean, just, it's out of this world. You can't believe such a thing can be happening.

CAPT. ERIC BROWN: I really couldn't see the logic in the cancellation. Everything pointed to a good potential chance of success. And I was really quite hopping mad at the time when it was canceled.

STACY KEACH (NARRATOR): For 50 years, the cancellation of the M-52 has been the subject of argument and secrecy. Ben Lockspieser was the civil servant who abandoned the project. He said it was too dangerous. The reasons why he came to this decision are only now becoming clear. At the end of the war, Lockspieser accompanied a number of British and American scientists who visited a secret aircraft research laboratory near Munich in Germany. All that remains today is the blocked-up entrance. But some of Germany's most talented aircraft designers once worked here—on designs that convinced Lockspieser the M-52 would never break the sound barrier.

SIR PETER MASEFIELD: I had the opportunity just after the end of the war to fly into Germany to have a look at what they were doing, or had been doing. One of the eye-openers which certainly impressed Benny Lockspieser very much was the quite novel idea of highly swept back wings. And they had advanced swept back wings which enabled them to go much nearer to the speed of sound. Benny Lockspieser came back from Germany convinced that swept wings were the only solution, and so he canceled the Miles airplane on the grounds that if he allowed it to go forward, he would be putting test pilots at very grave risk of the airplane going out of control.

STACY KEACH (NARRATOR): In December, 1945, just days before Britain's hopes were ended, the United States rolled out its first test plane. Called the Bell X-1, American engineers had also designed a thin, straight wing for their supersonic hopeful. The Bell team had considered giving the X-1 swept back wings, because they delay the formation of shock waves, and so help to minimize the turbulence. But in 1945, the idea was untested, and the Americans realized swept wings weren't essential for supersonic flight. If the aim was to fly rapidly through the sound barrier, thin, straight wings could do the job just as well.

DE BEELER: Without question, we actually had more information on the straight wing. So, if you sized up the various advantages and disadvantages, we had the smallest degree of risk to enter an area that we didn't have all the answers for, to go with a straight, thin wing. Frankly, I was a little surprised that the British didn't go ahead, because I have a good feeling they could have made it. With all due respect to the people responsible for the cancellation, I think they made a mistake.

STACY KEACH (NARRATOR): Britain was not the first to break the sound barrier, but for a while at least, it did have the world's fastest plane. The Meteor broke the speed record in 1946, flying at 616 miles per hour. But it would never fly faster than sound. That same year, British test pilot Geoffrey de Havilland was also vying for the speed record with a different kind of aircraft. Called the DH 108 Swallow, it was designed to study the high speed performance of swept wings. On the even of its speed record attempt, de Havilland took the plane out for a final test flight. He was never seen alive again. The Swallow had disintegrated during a high speed dive. Like so many before him, de Havilland fell victim to the destructive force of shock waves as he approached the speed of sound. The U.S. was now alone in the quest to break the sound barrier. In 1947, the Bell X-1 was handed over to the Air Force to test the plane's high speed potential. The pilot chosen to attempt the sound barrier was Captain Chuck Yeager.

BRIG. GEN. CHUCK YEAGER: I came up as number one, because number one, I could fly airplanes. I had been to the test pilot school. And I understood machinery. And because the X-1 would blow up on you real easy if you didn't know the system, and consequently, I knew the system. A lot of the systems in the X-1 were systems that my dad used in the natural gas fields in West Virginia. And I used to work on the diaphragms and the pressure regulators that were in the X-1 or similar. And so, it was easy for me.

DE BEELER: He had a mind of his own. And that's good. He listened to you, if you couldn't pull anything over on him. I mean, you couldn't sneak in something, "Hey, how about you try this?" Because he wouldn't buy it. He's a pretty savvy, practical individual.

STACY KEACH (NARRATOR): The Bell X-1 was taken to Muroc Flight Test Center in California for its record-breaking attempt. In order to conserve fuel for the flight, the X-1 did not take off from the ground. Instead it was flown up to its launch height strapped underneath a B-29 bomber.

DE BEELER: It was built extremely strong, like a battleship, for a purpose, in case we had problems near the speed of sound. And it was built about twice the strength of a normal fighter airplane at that time. And that corresponds to being able to carry its weight—about 16 times its weight. So, that means that a pilot can maneuver the airplane up to 16 times his weight and the airplane's weight before the wings would fail.

STACY KEACH (NARRATOR): The rocket engine in the X-1 did not inspire the same confidence. The dangerous and unforgiving nature of rocket operations was a constant source of worry.

DE BEELER: I went one time in the B-29 and watched the operation to check out the rocket engine. To me, I felt the whole risk of the program at that time with those speeds we had reached—our problems may have been around the rocket engine or the fuel or something that someone's goofed up mechanically.

STACY KEACH (NARRATOR): But on October 10th, the rocket motor behaved perfectly. Yeager reached 658 miles an hour. But at the edge of the barrier, he hit the very problem that had foiled everyone else.

BRIG. GEN. CHUCK YEAGER: When we got the airplane up to 94% of the speed of sound, and I'm sitting out there, and I decided to turn the airplane—I pulled back on the control column. Nothing happened. The airplane just went the way it was headed, and I said, "Man, we've got a problem." So, I raked the rockets off and jettisoned the liquid oxygen and alcohol, and came down and landed, and got the engineers together and we had a little heart-to-heart talk. I said, "We've got a problem, and because the airplane may pitch up or pitch down, I've lost the ability to control it."

STACY KEACH (NARRATOR): The X-1 would need more than a rocket engine and thin wings to break the speed of sound. Fortunately, the engineers thought they had the answer: a new all-moving tail. Other planes could only move a small portion of the tail. On the X-1, the entire assembly could move. It hadn't been used before, but they thought it might stabilize the plane. First, it had to be checked out.

BRIG. GEN. CHUCK YEAGER: And it's really interesting. See, being a mechanic, all we did was take the cowling off and squirt 3-in-one oil on it and run it up and down, up and down, until it worked.

STACY KEACH (NARRATOR): On October 14, 1947, they tried the new tail out for the first time.

DE BEELER: In fact, all the mechanics and everybody was around the radar truck, because that's where you had our communication coming in. And we stood there, waiting, listening.

BRIG. GEN. CHUCK YEAGER: When you get up to around 12,000 feet, you've got a sheet-type parachute on. You get on a ladder. It lets you down until you're opposite the door, and you slide in feet-first.

STACY KEACH (NARRATOR): Yeager was in considerable pain. On the eve of the flight, he had fallen off a horse and broken his ribs.

BRIG. GEN. CHUCK YEAGER: You're in a very dark hole under the B-29, and when you drop clear of the B-29, you're in bright sunlight. When I got above 94% of the speed of sound, the nose begins to come up on the airplane. I just cranked the leading edge up on the horizontal stabilizer to keep the nose down. When we went a little faster, the mach meter went off the scale and when it did, all the buffeting smoothed out, because the supersonic flow went over the whole airplane. And even I knew we had gotten above the speed of sound.

DE BEELER: At about that time, on the ground around the radar truck, we heard the sonic boom. And we had a satisfying feeling that we had gone beyond the speed of sound, that the unknowns that were suspected—Why, Chuck removed them. That's it.

BRIG. GEN. CHUCK YEAGER: The big thing that came out of the whole program was that we found out, in order to control the airplane through Mach 1, we had to have a flying tail on it. That was the first time we had experimented with this flying tail on the X-1. That really was the answer to flying at supersonic speed.

STACY KEACH (NARRATOR): At last, there was something to celebrate. But instead of a party, the Air Force ordered a news black-out. The flying tail and other details of the plane had to be kept secret. It lasted two months. In December, the story of the flight was on all the front pages. The Air Force was furious, and tracked down the news editor of an aviation magazine that had broken the story. The military considered it a breach of national security and called in the FBI.

ROBERT B. HOTZ: I thought it was ridiculous. The Air Force had had a press conference in July, in which they had unveiled the X-1 and released all of the technical specifications of its performance. There is no technical information in our story that hadn't been released six months before.

STACY KEACH (NARRATOR): The all-moving tail wasn't even mentioned in the article. The FBI investigation was quietly dropped. But with the Cold War beginning, the need for secrecy remained.

BRIG. GEN. CHUCK YEAGER: It was a very important secret. You know, I'd been in the military long enough, and I'd fought in wars and understood security. And it paid off. And it took the British and the French and the Soviet Union five years to find out that little trick that we found out with the X-1. It gave us a quantum jump on the rest of the world in aerodynamics. Had we blabbed our mouth, you know, they'd have known it at that time.

STACY KEACH (NARRATOR): During the Korean War, Chuck Yeager saw evidence that the all-moving tail was kept secret from the Soviet Union. But it seems the Miles team knew all along.

DENNIS BANCROFT: We thought the ordinary controls wouldn't work above the speed of sound. So, we had to make an all-moving tail plane, because an ordinary elevator would literally not function at all. We would go up to the speed of sound, lose all air control, and the aircraft would crash.

STACY KEACH (NARRATOR): One year after the X-1's historic flight, Britain broke the sound barrier with a one-third scale model of the M-52. Although unmanned and radio-controlled, it did finally vindicate the worthiness of its supersonic design. The model also used a rocket engine—not a jet—to power it through. It would be six more years before the first jet-propelled plane would break the sound barrier in level flight. The Bell X-1 was the first of an entirely new generation of experimental aircraft. It forever changed America's approach to aviation research, combining the forces of industry, government, and the military to build what none of them could do alone. With the X-1's success came the needed funds to delve further into the limits of flight, generating a host of faster, more sophisticated military aircraft. The fastest, the X-15, flew at nearly seven times the speed of sound. The lessons learned ultimately made possible the dream of supersonic passenger travel.

SIR PETER MASEFIELD: Chuck Yeager, in the X-1, started the ball rolling down this road which will take us into hypersonic speeds in years to come in which the man in the street can fly right around the world in relatively few hours.

STACY KEACH (NARRATOR): Even space exploration owes much to the pioneers who, half a century ago, refused to take no for an answer. An entirely new era in military and civilian aviation has been opened as a result of the determination and bravery of pilots who risked all to achieve the impossible.

ANNOUNCER: Half a century later, what's the fastest plane in the sky? Boat in the water? Car on land? Log on to NOVA's website for Speed Machines, at

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ANNOUNCER: Next time on NOVA, an IRA bomb has been planted. Someone must defuse it—quickly, safely.

BOMB DISPOSAL SOLDIER: If there's a piece of fishing line dangling off one of the doors, you might be in trouble.

formER IRA BOMBER: It's the most incredible power I had ever seen unleashed. And all from striking a box of matches.

ANNOUNCER: Politics and science make an explosive mix in Bomb Squad.

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ANNOUNCER: Coming up on NOVA, he conquered Fermat's Theorem and made international headlines.

SCHOLAR: It was so indescribably beautiful.

ANNOUNCER: The world of mathematics will never be the same.

SCHOLAR: I was flabbergasted, excited, disturbed.

ANNOUNCER: How did this man solve an enigma that mystified the greatest minds for centuries? The Proof.


Faster Than Sound

Produced and Directed by
Tony Stark

Associate Producers
Brett Lodge
Stephen Sweigart

Stacy Keach

Marc Davies
Stephanie Munroe

Howard J. Davidson

Nick Plowright
Waren Harrison

David Hall

Max Cole

Tom D. Crouch
Bill Gunston
Dr. Richard P. Hallion
Von Hardesty

Online Editors
Bill Ogden
Mark Steele
Doug Martin

Sound Mixers
Richard Bock
Matt Skilton

Additional Directing
Ingrid Geser

Production Manager
Flora Gregory

Executive Producer,
Lauderdale Productions
Andrew Forrester

Archival Materials
RAF College Cranwell
The San Francisco Chronicle
Lockheed Martin
Federal Systems
Royal Air Force Museum, Hendon

Archival Materials
Imperial War Museum
The Matthew Nathan Collection
Karl-Ernst Heinkel

Archival Materials
Great American Stock
Smithsonian Air and Space Museum
Paramount Pictures

Special Thanks
DERA, Farnborough
Science Museum
Miles Blackwell
The Miles Aircraft Collection
Mark Tuttle

NOVA Series Graphics
National Ministry of Design

NOVA Theme
Mason Daring
Martin Brody

Closed Captioning
The Caption Center

Production Secretaries
Queene Coyne
Linda Callahan

Stella Giamassi
Paul Marotta
Lisa Cerqueira

Nancy Marshall

Post Production Associate
Sandra Rizkallah

Post Production Editor
Rebecca Nieto

Post Production Director
Alison M. White

Unit Managers
Laurie Cahalane
Amy Trahant

Business Manager
Carolyn Birmingham

Science Editor
Lauren S. Aguirre

Senior Producer
Coproductions and Aquisitions
Melanie Wallace

Series Producer
Beth Hoppe

Managing Director
Alan Ritsko

Executive Producer
Paula S. Apsell

A NOVA Production by Lauderdale Productions, Limited for Channel 4 and WGBH

© 1997 WGBH Educational Foundation
All rights reserved.


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