I had about 3 months to prepare for my first flight. One of the first things I had to do was to be measured for a new pressure suit. The X-15 pressure suits were custom made for each pilot by the David Clark Company located in Worcester, Massachusetts. We had to make several trips to David Clark to be measured, fitted, and checked out in the suit. Once we got the suit, we could then be fitted into the X-15 cockpit.
The X-15 ejection seat was not adjustable. Consequently, each pilot had to have his personal seat pad, back pad, and armrest pad to position him properly in the ejection seat and the cockpit with respect to the windows, the various control levers and switches, and the side arm controller. We had to reach all of these controls and switches whether the suit was pressurized or unpressurized, so we had to check their accessibility both ways. It really was tough to reach some of the controls and switches when the suit was pressurized since mobility was significantly restricted. It was, however, interesting to note that the pilots did not complain about the lack of mobility when the suit occasionally pressurized in flight. Apparently, the abundance of adrenaline flowing during a flight allowed the pilot to easily overpower the resistance of the pressure suit. This same phenomenon was evident in a pilot’s evaluation of control forces. On the ground, the pilots often complained that the control forces were too high. In flight, they seldom noticed the forces. You obviously can move mountains when you have to and occasionally during a flight a mountain might get in the way in the form of an emergency.
The aeromedical doctors measured various physiological measurements on the pilots during flight such as heart rate, blood pressure, and breathing rate. They were quite amazed to find that the pilot’s heart rates peaked as high as 200 beats per minute during various portions of the flight. This was some of the first medical evidence of these seemingly excessive heart rates. These high heart rates did not really surprise the pilots. We needed that high heart rate to keep the old adrenaline flowing.
After being properly fitted into the cockpit, I spent many hours sitting there memorizing the location of all the controls, switches, circuit breakers, instruments, and escape system components. We learned to identify and actuate everything blindfolded. I spent many hours learning the details of the aircraft and its systems during classroom type presentations by the experts on each portion of the aircraft. I also listened to the experts on stability and control, performance, structures, flutter, aerodynamics, aerothermal heating, and energy management. I became an instant expert in all of these disciplines.
I averaged 2 or 3 hours a day in the simulator during the 2 months before my first flight, practicing the planned flight and practicing various emergency procedures. The planned flight was just over 6 minutes in duration, so I could practice it 10 times each hour. I estimated that I practiced that flight over 500 times before I flew it. I practiced every emergency condition that the flight planner could conceive. When I had finished my simulator training, I could predict the altitude, velocity, rate of climb, and dynamic pressure for each second of the flight.
During simulation, I was also exposed to all of the unique or unusual flying characteristics of the airplane. I learned about the poor lateral-directional characteristics of the aircraft at high angles of attack in the unaugmented control modes. I learned about all of the airplane’s minor handling qualities faults and abnormal response traits. I became a handling qualities expert on hypersonic airplanes.
I spent the remainder of my time before my first flight practicing unpowered approaches and landings, or “hurling myself at the ground,” as Bill Dana used to say when he described X-15 landing approaches. For 2 months, I flew an F-104 at every opportunity to practice approaches to the various lakebeds involved in my first flight. My launch lake was to be Hidden Hills, a long narrow lakebed just across the Nevada border. It was 130 nautical miles from Edwards. Hidden Hills was about 3.5 miles long and about 1 mile wide. Because of this narrow shape, there was room for only one runway. The lake was in a valley between two ridges but the ridges didn’t obstruct the approach path. All in all it was a good emergency lakebed.
My intermediate lakebeds were the Three Sisters Lakes and Cuddeback Lake. Two of the Three Sisters Lakes were large enough for X-15 runways but just barely. They were round lakes about 2 miles in diameter. They were about 60 miles from Edwards. No one really wanted to put the X-15 into Three Sisters. Cuddeback was a much better lakebed. It was long and narrow like Hidden Hills, about 3.5 by 1 mile. It also had only one runway oriented north and south. It was 35 miles from Edwards. The only obstacle near Cuddeback was a small mountain to the north that partially obstructed a right-hand pattern from the northwest.
A dirt road ran across the lakebed in an east-west direction from Randsburg mining town to a bombing range on the east side of the lakebed. This road was built up slightly above the level of the lakebed to make it usable when the lake was wet. Thus, the road reduced the usable lakebed to less than 3 miles by cutting off the northern portion of the lakebed. The bombing range to the east of the lakebed was heavily used by aircraft from George AFB. We had to restrict its use during X-15 flights to eliminate any potential traffic problems if we had to use the lake in an emergency. During our practice landings, however, we had to dodge traffic just like everyone else.
Typically on an X-15 practice flight, I would head uprange to the launch lake right after takeoff. By the time I got to the launch lake, I would have burned off enough fuel to allow me to make touch and go landings as soon as I arrived. At the launch lake, I would simulate two different type approaches, no engine light approaches and premature shutdown approaches. The no engine light approaches could get a little sticky because a pilot could lose quite a bit of altitude during the initial engine light attempt and the relight attempt. Only then could he turn toward the launch lake and begin the emergency landing checklist. He would therefore be low on altitude when he started his approach. A major concern in a no engine light situation was getting rid of all the propellant. By starting the jettison late, after the relight attempt, the pilot was marginal on getting it all out before landing.
The premature shutdown approaches were also occasionally dicey since the pilot had to get the airplane turned around and headed back to the launch lake. Depending on when the engine quit, he could get back to the launch lake with a lot of energy or he could get back with just enough to make a minimum energy approach. I would normally make two or three practice approaches at the launch lake varying my initial energy conditions and then head down range to the Three Sisters lakebeds. I would make a couple of approaches at Three Sisters from different directions and then head for Cuddeback. At Cuddeback, I would make a couple more approaches, and then climb out and accelerate toward Edwards to arrive with a lot of excess energy, usually supersonic above 45,000 feet. After making the initial high energy approach at Edwards, I would use up the remainder of my gas approaching from different initial energy conditions including some straight-in approaches.
We normally used the north-south runway on the northern portion of the Edwards lakebed. This runway was our prime runway and we normally landed heading south. Our alternate runway was zero-five, two-three also on the north lakebed. We used this one when we had high winds which were usually out of the southwest. All of the other Edwards lakebed runways were usable in case of unforeseen problems, but we very rarely used any other runway. Most of the Edwards lakebed runways were a minimum of 4 miles long and one runway was over 7 miles long. Now that is a REAL runway.
At Edwards, we normally made 360-degree overhead approaches into runway one-eight. High-key altitude was nominally 35,000 feet and low-key altitude was 18,000 to 20,000 feet. Airspeed in the pattern varied with each individual pilot, but usually ranged between 240 and 300 knots. We rolled out on final at about 8,000 to 10,000 feet, ideally at 300 knots in roughly an 18- to 20-degree glide angle. We maintained the steep final approach until about 1,000 feet above the ground and then initiated the flare for landing. The aim point during the final approach
was roughly half a mile short of the runway, which would result in a touchdown about a mile down the runway. The length of runway one-eight was 4.5 miles, so we had 3.5 miles remaining to slide out. I made this same practice flight at least four times a week for 2 months prior to my first flight.
On the day of my first flight I got up early and made a final practice flight before suiting up for my X-15 flight. As I remember it, the day of my first flight was a typical beautiful fall day in the desert. I felt good. I had gotten a good night’s sleep and I had had a light breakfast before my practice flight in the F-104. Roger Barnicki, our personal equipment specialist, met me after my practice flight and escorted me to a carryall vehicle for the trip down to the X-15 servicing area.
The X-15 servicing area was to me a rather eerie scene particularly early in the morning. There were dozens of people moving in and out of the darkness into the glare of the floodlights around the B-52 and the X-15. Numerous trailers, carts and other servicing equipment were sitting under the wing of the B-52 next to the X-15, while various liquids and gases were being pumped into tanks in the X-15. Liquid oxygen vapor was drifting all around the area like a swirling fog. A strong pungent ammonia odor permeated the air. The whole scene looked like something out of a Frankenstein movie. I would not have been surprised to see a monster walk out of the center of all that activity. In that setting, the black X-15 reminded me of some ominous creature—a menacing black bull.
Figure 5. Map of Edwards lakebed, showing a typical approach pattern.
Figure 6. Map of X-15 servicing areas.
After a brief glance at all that activity, I entered the suit van and immediately stripped down to my long Johns to begin the suiting up process. The first items attached to me were some biomedical sensors to measure heart rate, blood pressure, and respiration rate. Next came the inner pressure suit garment which resembled a reinforced rubber body suit with many hoses, knobs, and other fittings attached to it including a big metal neck ring. Getting into that garment was a real chore. It was designed to enclose the entire body and yet, the design did not seem to provide a big enough opening to get into it without some real body contortions. I preferred to have my suit fit very tight to minimize the ballooning effect when it was pressurized. Excess ballooning severely restricted mobility. My suit fit like a full body girdle. Although my suit was extremely tight and uncomfortable in an unpressurized condition, it was worth enduring that to have good mobility in case I should lose cabin pressure and be forced to control the airplane while in an inflated suit.
Once the inner garment was all zipped up, I was then helped into the outer garment which was a silver-colored coverall made of a nylon-type material. This garment was simply intended to protect the inner garment from the effects of wind blast and aerodynamic heating in case the pilot ejected. Next came the boots, gloves, and finally, the helmet. A lengthy checkout of the suit followed. This involved pressurizing it and checking all the joints for integrity, leakage, and mobility. The whole process reminded me of movies that I have seen about warriors in ancient times being dressed for battle in their suits of armor.
The pressure suit was quite critical in X-15 flight operations since it was not uncommon to lose cabin pressure during a flight. In addition, it was the pilot’s only source of oxygen because the cockpit was filled with nitrogen. The pilot could not open his faceplate to breathe. The pressure suit was to be my cocoon for the next couple of hours.
When the suit was finally checked out, I had a few minutes to relax before the aircraft was ready for pilot entry. As I sat there relaxing, my thoughts drifted back in time to an earlier era of exploration.…
The early morning light revealed a small ship drifting idly on the calm sea off the shore of a barren land. At the stern of the ship a group of men were gathered around a young man seated on a small bench. The men were fastening armor to the young man’s body, carefully setting it in place and then adjusting the straps. They strapped other pieces of armor to his arms and legs and then some heavy leather boots on the young man’s feet. Gloves were then fitted to his hands and finally a helmet was lowered down over his head and the visor closed. The men helped the young man to his feet and escorted him up the deck of the ship to the bow.
At the bow of the ship another group of men had been fitting armor to the body of a huge, black bull. They had also placed a saddle on the bull’s back. The bull was restless and strained against his tethers and vapor rose from his body in the cool morning air. The young man climbed up a ladder next to the bull as the men assisted him into the saddle. They then strapped him to the saddle and fastened his feet in the stirrups. They slipped his sword into its scabbard on the saddle and handed him his shield and his spear. The crew of the ship then raised the sail and the ship began moving toward the shore.
As the ship approached the beach, an old man spoke to the young man on the bull. “We have provided you arms and armor to protect yourself. We have provided you a sturdy mount who will carry you safely on your journey. We have told you all we know about this strange land. Thus we have prepared you for this journey as thoroughly as we can. We have provided you protection from any danger that we could foresee. Now you must go and explore this strange land and then come back and tell us what you have learned. But before you go, one last word of caution: Beware of the bull. He will carry you safely anywhere that you have to go and he will protect you from any enemies. He is awesome in battle. However, if you lose control of him or fall off, he will kill you as quickly as he would kill your enemy.”
As the old man finished talking, the ship slid to a gentle stop on the sandy beach. A gangplank was lowered and the young man rode the bull down onto the beach.
Like the warrior, I too had a sturdy mount, the X-15. I had also been painstakingly prepared for my journey. I had been indoctrinated into the unexplored world of hypersonics, a region of strong shock waves and intense heating. The aerodynamicists explained the rationale for the aircraft configuration, the benefits of the wedge-shaped vertical fins, and the theoretical performance of the aircraft. The structures engineers described the structural design philosophy and identified the critical load conditions. The aerothermodynamicists explained the effects of aerodynamic heating and the resultant temperature environment on the surface of the aircraft. The stability and control experts defined in minute detail the predicted flight characteristics of the aircraft at every conceivable flight condition.
The systems engineers inundated me with schematic drawings showing the components and the mode of operation of each subsystem. I became an expert on APUs, inertial platforms, ballistic controls, ball noses, nitrogen cooling systems, rocket engines, pressure suits, and instrumentation systems. I had huge binders full of notes taken during lectures on the aircraft, the environment, and the protection provided me in case of an unpredicted problem. I hoped not to encounter any surprises or lose control of the aircraft.
A call for pilot entry brought me quickly back to reality. Pilot entry took on the aura of a ritualistic ceremony. Two of the personal equipment specialists walked along with the pilot and carried the portable liquid oxygen cooling system and other equipment in a manner similar to the squires who served the knights and warriors of ancient times. The servicing crew and the aircraft crew were generally waiting for the pilot, standing along his pathway out to the aircraft and on the ramp up to the cockpit. It appeared as though the pilot was walking the final steps to the altar to be offered up to the gods. This very dramatic pilot entry made it tough for the pilot to back out of flying that mission. Everyone could see that he voluntarily walked out to the airplane and climbed in under his own power. He could not say that he was coerced or forced into flying the mission. He was like the Kamikaze pilot. He had drunk the wine and had accepted the sword. He could not turn back. He had to fly the mission.
Luckily, the pilot was rather busy once he got in the cockpit. He did not have a lot of time to worry about whether he was going to live or die. In fact, the tempo picked up as it g
ot closer to launch. The pilot was, in effect, too busy to think about aborting the flight until after launch, and then it was too late. He could not turn back. He did not have a reset button like he had in the simulator to stop the flight and return him to the starting conditions. That is a nice button to have. If we saw that we were going to crash in the simulator, we just hit the reset button and we were back to our starting conditions. Every airplane should have a reset button.
The pilot had a lot of help getting into the cockpit and getting all of the lines, hoses, and straps hooked up. Following all that activity, he again went through a pressure suit checkout and then began the cockpit checkout. During this process, he went through a detailed checklist with an aircraft inspector assisting him in verifying the status of all the aircraft systems and the position of every switch, lever, and circuit breaker in the cockpit. He verified that he had good X-15 systems, as well as good system support from the B-52 bomber.
While attached to the B-52, the X-15 was supplied several expendables through various lines and an umbilical cord. One of these was liquid oxygen to top off the X-15 liquid oxygen tank. Boiloff of the liquid oxygen in the X-15 was quite rapid. The B-52 routinely transferred 600 to 800 gallons of liquid oxygen to the X-15 during captive flight before launch. The B-52 carried about 1,200 gallons of LOX for this purpose. In addition to LOX, the B-52 also provided breathing oxygen for the X-15 pilot, electrical power, radio and intercom communications, and data to align the X-15 inertial platform. The only thing they did not provide was window washing and restroom facilities. Restroom facilities would have made a tidy profit for the B-52 crew. Every once in a while, the X-15 pilot had to spend as much as 3 to 4 hours in the cockpit due to various delays on the ground or in flight before launch. It was touch and go on a number of occasions.
At the Edge of Space Page 21
