Chapter 36: ►

_The Reluctant Dragon_

At 0730 on April 1, I climbed into the X-15 cockpit, ready for a second “captive” flight. Although we had learned a great deal on the first, none of us felt the ship was quite ready for a free glide to earth. First, we would make another dry run, to be sure. In the intervening two weeks we had made many improvements on the X-15. The temperamental APUs had been pulled out, rebuilt, and tested in repeated “runs” on the ground. We had removed the canopy and baked it in a hot oven for hours to purge it of the water trapped in the insulation, and then waterproofed it. As a further precaution against windshield icing, the nitrogen defogging gas was routinely turned on three hours prior to take-off. By Stormy’s edict, we had installed a radio intercom between the X-15 and B-52, which would, in theory, keep a line of communication open to me, if the single X-15 radio transmitter conked out at a crucial moment.

As usual, there were some pre-take-off delays. The men swarmed about the fuselage of the X-15, pulling wires and making last-minute repairs which were checked and rechecked by the ground service cart operators. The X-15 panel was alive. I sat staring at the lights and gauges looking for signs of trouble. By that time I had spent at least three hundred hours in that cockpit and I could sense a fault or impending crisis almost subconsciously.

At 0812 Oscar Freeman and Pete Barker slammed the X-15 canopy shut. Charlie Bock and Jack Allavie wheeled the giant mother plane to the take-off runway and cobbed the engines. At 0844 the wheels left the ground and we were airborne for the second time. I tested the new intercom (unsatisfactory) and droned off the gauge readings, making a “data burst” every five minutes. At 25,000 feet altitude the X-15 radio transmitter and receiver, perhaps because of the intercom modification, faded drastically. But the windshield remained clear. The chase moved in close and we droned skyward for a launch rehearsal.

At 25,000 feet altitude, I could faintly hear Q. C. Harvey come on the radio circuit: “I guess we’ll have to abort. I can’t hear Scotty. His radio is out.”

I already had the transmitter on, but the amplifiers were not putting out. Breaking a long-standing personal rule, I shouted as loud as I could over the radio mike: “No, Q.C. No. No. Don’t abort. No abort.”

“Okay, Scotty,” Q.C. replied. “I can just barely hear you, very faint and intermittent.” Determined that a simple radio malfunction would not stop the test, I shouted myself hoarse. Then Q.C. came up with an ingenious, spur-of-the-moment solution to our radio difficulty.

“I can hear your mike loud and clear when you key it, Scotty. But I can’t hear your voice. We’ll follow a system here. You key your mike in response to my questions. One dick means yes. Two clicks mean no. Okay?”

I keyed the mike one click.

Following this system, we worked through the thirty-page flight check-list with Q.C. in command on the ground. “Okay, Scott,” he would say. “We have completed item 10. Are you ready to go to item 11? Repeat, are you ready to go to item 11?” If I was satisfied, I responded with one click of the mike. If I did not think the ship was ready for the next item, I transmitted two clicks. Slowly we accumulated the necessary data, which included various severe maneuvers of the B-52, a carefully monitored speed run to check the X-15’s air-speed indicator, and finally the big item, the launch rehearsal. The APUs came on the line and held steady, purring like kittens.

Taking advantage of our good luck, we circled Edwards for well over an hour and a half. When I noted the coolant for the APU bearings was getting dangerously low, I waved my hand at the B-52, suggesting we return to base and land. Bill Berkowitz, the launch-panel operator, watching the X-15 through a closed-circuit television installation, caught the signal and relayed my request by radio to the ground. Q.C. came on the line:

“You want to land, Scott. Correct?”

I keyed the mike one dick, and Charlie Bock banked toward the Edwards runway. We dropped the X-15 gear for a routine test, and shortly thereafter Bock greased on, one hour and forty-four minutes after take-off.

* * * * *

Except for the simple radio failure, the X-15 had performed well on this flight. But the full-pressure suit had not. The seals were leaking, and the valves failing. In fact, in the post-flight report, I noted thirteen discrepancies in the suit and asked that the Clark company send a team to Edwards without delay to make the necessary modifications and adjustments. With all our tests on the ground and in the air, we were wearing the suit out. On one of the hundreds of ground tests I nearly killed myself.

It happened right in the X-15 cockpit while the canopy was open. Decked out in the suit and helmet, I was running a test which involved innumerable selections of oxygen supply, on, off, on B-52, on X-15, etc. I made an error and got out of sequence. I proceeded with the test, breathing not X-15 oxygen as I supposed, but the nitrogen gas suit coolant which was leaking into the helmet through a crack in a rubber seal. There were several ground crewmen working about the X-15, and Pete Barker was bending down in the cockpit helping me with the test. Nobody was aware of the developing crisis.

Nitrogen gas is an insidious suffocant. Man cannot long survive breathing only nitrogen. Quite soon I began to feel its effect. The instrument panel facing me seemed to be floating away. I gazed in wonder at this phenomenon for several seconds, too stupefied to realize my predicament, then I drifted off into unconsciousness. Barker, working with me on the test, still had no inkling of the danger.

By the grace of God I suddenly snapped back into momentary consciousness. Bewildered, I sought to escape from my slow suffocation. Not knowing what caused the blackout and dizziness, and unable to think clearly, I was desperate. I clawed helplessly at the fittings of my helmet, and then cast up my arms in one final protest and, as I recall it dimly, probably yelled.

Luckily for me, Barker saw me raise my hands and sensed trouble. He jerked off the helmet in the nick of time. I feel I owe my life to his quick response.

* * * * *

On the evening before an X-15 flight was scheduled, Stormy always came up to the desert for a last-minute look-see. He checked in at the North American hangar, talked to the X-15 mechanics, and toured the mating area, where the men were working to attach the X-15 to the mother plane and to check out the systems. When Stormy was satisfied, the two of us slipped away and drove far down the desert to a remote roadside restaurant, where we could lay plans during dinner without interruption. On April 13, the eve of the third flight, Stormy was restless and quietly angry. He was involved in a tight poker game with high stakes. Like all the rest of us, he wanted to see the X-15 fly--and the sooner the better. But we knew that if we pushed too hard and fast and something catastrophic happened, the country would suffer a black eye and we and the company would be severely criticized. At the same time, if we didn’t show more promise, we would be chided for dragging our feet. Thus Stormy--all of us in fact--was seeking to strike a balance between fast action and sound technical advance. Ridiculously petty items were sabotaging us: APU regulators, radio intercom wiring, two-dollar valves--horseshoe nails that could conceivably lose us a kingdom. Each time we aborted a flight we lost two weeks, the time it took to “turn around” the X-15 or prepare it for a new trip into the air.

Stormy is one of the few men I have met in my life whom I sincerely admire. I like his approach to building airplanes. He is not only enthusiastic and eloquent in presenting his case for this or that airplane, but also he is more technically honest than any engineer I have ever known. If something doesn’t work, it doesn’t work, and it is discarded. He doesn’t prolong it, building an empire of paper-pushers. He knows how to take on a job and do it right. And once he begins, he is completely objective and ruthless about it.

“We’ll play it like this,” Stormy said. “Tomorrow we’ll go through rehearsal. If the APUs look okay, go through another rehearsal. If everything seems to be going well, then we’ll drop. But wait for the word from me. The final decision to drop, of course, is yours.”

* * * * *

Just after dawn the following morning I climbed in the X-15 cockpit and droned the gauge readings into my portable tape recorder: “Liquid nitrogen source 3700. Number one hydraulic temperature 18 degrees. Number two hydraulic temperature 5 degrees. Number one APU source pressure 3500. Number two APU source pressure 3500....” As far as the X-15 was concerned, everything was near-normal. Except for a radio line in the helmet, which was snagging on the neck seal, the Clark suit was working well. It had been completely overhauled in the past ten days by Clark’s experts.

After reading the gauges I stared at the instrument panel, waiting for the ground crews to seal up. Stormy, wearing a gabardine topcoat, was huddled with Q. C. Harvey and Sam Richter next to the communications van.

At 0823 Charlie Bock released the B-52 brakes and we rolled down the runway to begin the third X-15 flight. When the B-52’s wheels lifted off, the three circling chase planes squeezed in close and climbed out toward what I hoped would be, by Stormy’s decision, our first launch. I was anxious and eager. By then we had been grooming the airplane for five months. To gain added X-15 performance, the launch altitude was raised from 38,000 to 45,000 feet. It took almost an hour to reach peak altitude.

After the usual checks of the pressure suit, the X-15 cabin pressurization, and some special B-52 speed-tests and maneuvers to feel out the “mating” at that extreme height, we proceeded to the first launch rehearsal. Everything worked perfectly--almost. Radio communications were good, and the APUs came on the line with no trouble, although we expected trouble at higher altitude where the temperature is colder. I deliberately opened the ram-air door to try to fog the windshield. It remained clear. We simulated a drop and closed down. Then Bock wheeled the B-52 through a gigantic ten-mile turn high in the sky to repeat the rehearsal. The chase planes, hanging in the thin air at reduced speed, struggled to keep position. Our path through the sky was marked by seven white contrails.

For the second time on that flight we moved in to a launch rehearsal. I started the APUs again, anxiously awaiting the key words from Stormy on the ground. But Stormy, who was watching and listening at Sam Richter’s truck out on the lake bed, didn’t say a word on the radio. His intuition told him the time was not ripe. With no positive word from him we continued the launch rehearsal and at one minute before drop time aborted the flight. I was quite disappointed.

As a matter of routine, after launch rehearsal on the descent to Edwards, I kept the APUs on, so that the X-15 would have power in the unlikely event that an emergency arose and Charlie Bock had to cut me loose in a hurry. The APUs were still running as we descended through 42,000 feet. At 41,000 feet both APU generators suddenly dropped off the line. I recycled number one and got it back on, but number two refused to connect. I reported this by radio.

A few seconds later I became aware of an ominous, heavy vibration somewhere in the after end of the X-15. Something was quite wrong. My eyes automatically swept across the gauges; my ears tuned to the growing rumbling. Number two APU had failed. I was not aware of the full extent of the malfunction then, but I knew it was serious. Later we discovered that the unit had seized and shaken completely off the mounts. This severe wrench also disturbed the second APU. I shut both units off, thankful then that Stormy’s intuition was working. A minute later I noted a wisp of smoke in the cockpit.

This time there was no connection between the APU failure and the smoke. A wire in one of the cabin blowers simply overheated and caused the insulation to smolder. I was tempted to ignore the smoke because nothing strikes fear in the hearts of the ground people quite so rapidly and decisively as smoke or fire in a rocket airplane. But one of my duties as test pilot was to report _every_ routine and non-routine event in the X-15 cockpit. Reluctantly I passed the word on the radio circuit and, as expected, there was quite a bit of excitement on the ground. But the smoke diminished and by the time we reached the ground, an hour and nineteen minutes after take-off, it had disappeared altogether.

When we parked in the mating area, the ground mechanics opened the doors on the APU access compartment almost immediately. Charlie Feltz, Stormy, and I peered in at the shambles of metal that had once been two highly refined, critical pieces of X-15 machinery. The APUs at that point had been under laboratory and field test for a whole year, yet they were still obviously a long way from being reliable. Sick with disappointment, Stormy hurried off to Los Angeles to set in motion words and action that soon solved the X-15 APU problem. I don’t know how much money and time were spent in the extensive APU rebuilding and testing that followed in the next few weeks, but I do know that with one exception in the year that followed we had no more APU trouble.

These APU problems, which I probably have dwelt upon at too great length, were not confined exclusively to the X-15 rocket airplane. Other companies were having much the same kind of trouble in ballistic missiles. At Cape Canaveral scores of multi-million-dollar birds blew up on the pads or in flight because of APU failure. This is one part of the price of progress, of probing into the unknown. The big advantage in the X-15 was that we did not lose our bird. With a pilot at the controls we were able to detect and avert fatal trouble, and save the ship for another flight. We could bring the broken APUs back to earth in one piece--or sometimes in one piece--for engineering analysis. The fixes we made, I hope, were passed on to the missiles at Cape Canaveral. Thus in one sense the X-15 was already beginning to pay its way as a research tool.

After the flight Captain Richardson was waiting in the 16th Physiological Training Unit van with the usual martini. It tasted weak. I commented on this while squirming out of the pressure suit.

“It’s watered down,” Richardson said.

“What?”

“That’s right. If you can’t pull off a full-blown flight, you don’t get a full-blown martini.”

Ribbing of this kind was directed toward us from many official sources. Our tiger was gaining a reputation for being a Reluctant Dragon. This hurt in more ways than I can remember.

* * * * *

21 May, 1959. Thirty-one weeks had flown by since we trucked X-15 number one to the Edwards test base. Seventy-two days since our first shaky captive flight in the airplane. Forty-one days since captive flight number three. NASA and the Air Force were becoming increasingly anxious and no longer hiding it. Our saga of troubles had stung the X-15 flight-test team badly. Every man felt a personal responsibility. Each worked with an intensity and devotion that no amount of money could buy, and at last we were ready to go into the air once again. This time there was no talk of a drop. Our sole objective was to stage a completely successful captive test, to prove that all the machinery of the X-15 would perform as designed under flight conditions.

On this climactic day, when they placed their mechanical stethoscopes to “listen” for signs of trouble in the X-15, the ground crews were more meticulous than ever before. They checked every system three times over, and then once again. Although I knew we couldn’t possibly take off before 0900, I climbed into the X-15 cockpit, fully rigged in the pressure suit, about 0700. I did this mainly for morale-building purposes. I wanted the ground crews to know that I had confidence in the airplane and that I was ready--eager--to get into the air. It was an uncomfortably long wait, yet a necessary one, I believed.

It was 0922 by the time Bock and Allavie lifted the B-52 off the runway. We were late but the X-15 was tuned to a fine pitch. A few minor items cropped up, as usual--a screeching in my radio receiver, an insufficient flow of nitrogen coolant in the lower half of the pressure suit--but during the familiar launch rehearsal the X-15 ran a jeweled watch. We circled Edwards for an hour and fifteen minutes, starting and stopping the APUs with no difficulty. The APU bearings, cooled by nitrogen gas, held to a normal temperature range: about 115 degrees Fahrenheit.

It was clear now that we were over the big hurdle. We would have stayed aloft longer that day, but the supply of APU nitrogen gas coolant, designed to last only for a normal X-15 flight of about half an hour, was dwindling rapidly, and as I have said before we preferred to land with APUs operating in case Bock had to cut me loose in emergency.

During the gradual descent the APU bearing temperatures began to climb. Number one reached 245 degrees; number two moved up to 200 degrees. I was not unduly concerned. The bearings, G.E. had calculated, could reach 400 degrees without seizing. Certainly we could keep below that figure. To decrease the drain on the single nitrogen gas supply, I turned off the windshield defogging and pressure-suit ventilation. But the diminishing supply of nitrogen gas to the APUs was not sufficient. Number one crept up to 295 degrees. I watched the gauge closely. If it got much hotter, I intended to shut it down and make the descent on one APU.

At 15,000 feet number one APU had inched ahead to 350 degrees. Since it was approaching a danger point, I reported the fact by radio to Q. C. Harvey. After consulting his panel of X-15 experts, gathered near his mike in the NASA tower, Q.C. responded:

“Scotty. Q.C. We suggest you shut down number one APU if the bearing temperature reaches 395 degrees.”

“Okay, Q.C.,” I replied. “That’s what I was going to do. Number one bearing temperature is now 376 degrees.”

My eyes were glued on the number one APU bearing gauge. It moved steadily ahead: 376 ... 380 ... 390 ... 395. I reached for a switch on the instrument panel and turned it, reporting by radio:

“Number one APU 395 degrees. Shut down.”

My eyes remained on the gauge. I expected it to “coast” still higher for a moment or so and then drop off rapidly. The gauge swung to 400 ... 416 ... 430. Number two APU, which was then getting all the nitrogen gas coolant, leveled out at about 200 degrees, as expected.

I snapped into my mike:

“Q.C., this damned number one is up to 450.”

“You can expect it to peak a little bit and then fall off, Scotty,” Q.C. replied.

“Yeah,” I said. “I know. But it isn’t falling off. It’s now up to 460 and climbing. Number two is okay, steady at 200 degrees.”

When the temperature of number one APU reached 475 degrees, I heard a familiar rumbling in the rear of the X-15. The unit had seized and vibrated to a stop. But why? Then in a flash I realized I had made a dreadful error. I had not shut down number one APU at all. Instead, I had shut down number two.

“Holy smoke,” I muttered on the radio circuit.

My spontaneous comment touched off a tremendous flurry of excitement on the ground. Sam Richter came on the radio instantly.

“Scotty. Did you say smoke? Repeat. Do you have smoke in the cockpit?” (I later learned that Charlie Feltz, who was in Sam’s van, and whose ear was not then attuned to airplane radio circuits, leaped from his chair and said: “Wha’d he say? Wha’d he say?” And thereafter “Wha’d he say?” became a very big joke on the X-15 team.)

“No. No. Sorry,” I replied. “No smoke in the cockpit. I just goofed. I shut down number two APU by mistake. Number one was running all the time. It blew.”

It took only the thinnest imagination to conjure up the disbelieving expressions which spread over the faces of the people on the ground. After six agonizing months of APU difficulties, we had finally made a successful airborne demonstration. Then at its climax I had stupidly blown an APU because I turned the wrong switch. Short of losing the airplane altogether, no mistake I might have made in the air that day could have stung our team deeper. They could not have been more depressed. I felt like a fool, and of course I assumed full responsibility for the blooper.

The APU failure was properly judged pilot error. Since everything, including APUs, was considered satisfactory, all hands agreed the ship was fit for her next great test, the first glide flight to earth.