That wasn't the end of the release problem, either. In late November, the damned safety pin stuck again. Once again, I sat in there, dangling. This time, one of the crew, a big red-headed sergeant, came down the ladder with a hammer. That dedicated nut stood on the fuselage of the X-1, pounding on the safety pin stuck in the shackle release. He wore a chute and an oxygen mask, but if he did knock out the pin, we were going to drop as a team. I watched him from the cockpit window, thinking, "Man, that guy is pure guts."
On one of those shackle problem flights, I was dropped in a stall, fought it successfully, only to discover that none of my rocket chambers would ignite! I thought, "My God, what next?" I finally got two chambers lit and we rocketed up. One chamber never did fire; nevertheless, I flew out to 1.07 Mach that day. In between these problems, I had already flown out to 1.35 Mach at 48,600 feet-about 890 mph, or twice as fast as I had ever flown in a conventional Mustang during the war. The myth of a sonic barrier was destroyed, but many questions about aircraft stability and control remained. Flying supersonic was becoming almost routine with similar flight characteristics revealed on every mission: light buffet and instability between .88 and .91 Mach, decrease in elevator effectiveness between .94 and .97 Mach, and a single sharp bump, similar to flying through "prop wash," while accelerating through .98 Mach. Decelerating from supersonic speed, I would experience all of these effects in reverse. Meanwhile, we were gaining invaluable data. I was flying the X-1 twice a week, while in between doing all kinds of flight and service testing on other airplanes.
By January 1948, I was outfitted in a pressure suit and began to resemble a spaceman. The plan was now to drop me at 30,000 feet, instead of 20,000 feet, giving me more fuel for higher climbs to 50,000 feet and beyond. Until now, most of our problems had been peripheral to the ship itself. But that quickly changed.
Toward the end of January, I was at 38,000 feet having just leveled off after achieving 1.10 Mach, when I heard an unusual noise in back. It sounded like an oil stove burning too much fuel. A high frequency vibration began shaking me in the cockpit. I glanced at the instrument panel and noticed smoke hanging in the still air. Even though there was no fire warning light, I quickly turned off the engine, dumped remaining fuel, and landed. Fire is the pilot's terror, especially in the X-1. I sat in the nose just waiting to be blown to pieces because I couldn't see what was happening in the back. After I landed, the crew found a small fire had burnt insulation in the engine compartment. I was shaken. On the next flight, while I was climbing to altitude, I turned on chamber number four and saw the pressures climb too high. I turned it off immediately, but the fire warning light came on, and I quickly aborted the mission. The crew found that the motor cowling on number four was badly burned. I was really worried now. And the following flight, I not only suffered another fire warning light, but the cabin filled with dark smoke.
You're sitting on volatile fuel and if it goes-pooh, you're gone with it in a flash. But there was nothing I could do to save myself, except sit there and sweat it out. The fire warning light glaring from my instrument panel means I'm burning back there. If I hit the jettison fuel switch, I've got to worry that my fuel lines are burnt out, so I may be dumping all that fuel directly into an engine fire. So you sweat helplessly, knowing there's a critical point where you've got to make your move to dump fuel. Your engines are shut off and you're losing altitude fast. The chase planes are far below and can't tell you what's pouring out of your engine. You're all alone and nobody is in the position to help you decide what to do. I know more about what's happening up there than Ridley or Frost. Finally, when you can't wait a moment longer, you hit that jettison switch and tense.
Nothing happens. You breathe again. You start setting up your landing pattern and speed. You watch your nitrogen gas pressure because if you use it up there's nothing left to force out the fuel or blow down the flaps and landing gear. You land soaked in sweat. After three straight flights like this, I marched on Jack Russell, our crew chief. "Hey, Jack," I said "goddamn, man, fix this thing before I blow to pieces."
This went on flight after flight, through February and March, seven or eight flights in all. Every time I started up an engine, the fire warning light would flash, and the cabin filled with smoke. The problem made no sense. I began to wonder whether or not the X-1 was really designed to do the kind of high-speed, high-altitude testing we were attempting. Frankly, I didn't know what to think, and neither did Jack Russell. He and his crew broke down that engine piece by piece, ground tested it, then Jack stuck his head inside the engine and poked around with a flashlight. He couldn't find anything wrong.
Meanwhile, the problem was really getting to me. I never showed any emotion, and I always stayed cool in these emergencies, so not even Jack Ridley understood what I was really feeling inside. I was scared. I crawled into the X-1 feeling like a condemned man. And I began having really bad nightmares, dreaming I was being burned alive inside the X-1, only to have Glennis shake me awake just as I was trying to jump out of our bedroom window that was shaped like the X-1 door. She would get me calmed down, but she was shaken, too. Until that point, I had never brought my apprehensions home. Seeing me so afraid scared her, even though I purposely didn't tell her what it was all about. Maybe if Andy were around, I would've confided in him. Ridley was worried enough, and I didn't want to add to his burdens. But I was miserable in secret.
Finally, Bell's engine designer came out and discovered the cause of the problem: the wrong gaskets were installed during one of the engine overhauls. I flew the X-1 a couple of times more, and after my twenty-third powered flight, during which none of the engines ignited because of a short in a cut-off switch, Colonel Boyd thought I'd had enough for a while and ordered me to take a break. I didn't argue. Two other Air Force test pilots flew the X-1 missions for a Couple of months. Pard Hoover was out, he broke both legs bailing out of his burning Thunderjet when the air stream slammed him into the ship's tail.
Over the next year, a half-dozen test pilots achieved Mach I or better while flying the X-1, and because I knew the systems so well, I flew chase for many of them. Jack Ridley finally got his chance to fly the orange beast, too. I was right behind him in a Shooting Star when he was dropped. He fired up his rockets and smoke appeared around his instrument panel. "Hey, Yeager, I got a fire warning light." I told him, "Hell, Jack, you're in a pure nitrogen environment. Nothing in that cockpit can burn." He replied: "The hell there isn't. I'm in here."
He decided to go for it anyway, and off he streaked, achieving 1.23 Mach. He landed like a little kid who had soloed for the first time on a two-wheeler. He said to me, "You son of a bitch, you made it all look so easy, especially the landings. That lakebed is treacherous."
It was true. Pilots complained about sun glare that blinded them from seeing the instrument panel, and a couple of them dinged the X-1 trying to land it. One pilot dinged it twice. Another had his door fly off as he was gliding in. Still another had his windshield blow out-a very hairy moment. Bad luck and maybe a lack of feel for machinery caused several of these tense moments. And while few of them would ever say so, I think that those who actually flew the X-1 realized that piloting the orange beast was a lot tougher than I had made it appear. Even Colonel Boyd admitted that. The old man came out to fly it. I suggested that maybe he'd want to start with an unpowered glide flight to get a feel for the ship, but he said, "No, I don't have time to waste. We'll go for a powered flight. I want to go as fast as that thing will fly." We developed a flight profile where I would chase him in an F-86 and be in constant communication, positioning myself to be at his side for the lakebed landing.