_Minor Miracles_
The year 1959 was a shake-down ride for the X-15. In her first
year at Edwards the ship was carried aloft fifteen times. Two of
these trips were planned captive flights with no intent to launch.
The other thirteen were serious attempts to fly. On nine of these
thirteen trips some part of the X-15 failed and the attempt was
called off. Of the remaining four trips one was the first glide
test. The other three were rocket-powered flights. Of the three
rocket-powered flights only one was completely successful. The other
two began or ended in serious emergencies, traceable to the “proven”
X-1-type rocket engine. Moreover, a fire on the ground during a
routine grooming gutted the engine of one airplane. One X-15 cracked
and split open on landing.
These failures, heartbreaking as they are, are common to all new
high-performance airplanes. In the case of the X-15 we, as old hands,
had long since learned to live with them. They laid the foundation
for a razzle-dazzle success story which immediately followed in 1960.
The X-15 suddenly came out of the mire, flexed her wings, and took
off with a speed and reliability that startled even us. We more than
doubled her flight-test rate and at the same time almost eliminated
all aborts. From January to late May--less than six months--the X-15
was carried aloft sixteen times. Of these sixteen tries only three
were canceled. The remaining thirteen flights were rocket-powered
runs, with only minor technical difficulties or none at all. On one
of these flights our bird flew faster than any other plane in history.
For a little while, though, in early 1960 it looked as if we would
never get off the ground. Both number one and number two X-15s had
been repaired. New and stronger landing gear was installed. The birds
were tuned to perfection, as were the two B-52 mother planes. But
heavy rains flooded the Edwards dry lakes. For a time we believed
the lakes might be closed for several months. Impatient to roll, we
investigated the possibility of launching at a distant lake near
Tonopah, Nevada. For some reason this lake seemed immune to the
capricious desert weather. It was dry as a bone. We moved some of the
X-15 ground crew and communications team to Tonopah. When the rain at
Edwards fell off and the lakes began to dry, we canceled the Tonopah
emergency plan.
On our first flight in 1960--January 23--we took off very late in the
afternoon, having been delayed several hours by an airplane which
crashed and tied up the main runway. I was riding X-15 number one,
which I had yet to fly under power. The launch--at 45,000 feet--was
rough. I rolled hard right and then left and was slow lighting the
engine. But once I got it going, the ship took off like a jack
rabbit, pushed along by a hundred-mile-an-hour tailwind. The airplane
felt cranky and ill at ease. I kept a tight grip on both control
sticks to hold her steady. Even so, she flew like the wind. Tracing
a huge circle of rocket exhaust over the Edwards base, I performed
some special maneuvers laid out in the flight plan. She pushed up
to Mach 2.6--1700 miles an hour--and the chase lost me completely.
Only Everest and Apt had flown faster and we were reigning even with
low-powered engines.
I was exhilarated. Seventy-nine days had passed since my last
previous X-15 powered flight. The ground crews felt happy, too, I
knew, because the strict radio-circuit discipline was observed by
no one. I keyed my mike in flight and _sang_: “Back in the saddle
again!” Letting down on final, I radioed Q. C. Harvey and asked
him if he’d like me to drive the X-15 up on the NASA ramp. When he
replied, “Sure,” someone else cut in on the circuit and said: “You’d
better get someone to open the hangar door!” A friendly needler,
recalling my near-disaster with the F-100, cracked: “Yes, at both
ends.” The landing was the best I’d ever made. I came in at 220 miles
an hour with a 7½ degree nose-up angle. Because of the delays, I had
spent eight hours in the pressure suit. In more ways than one, it was
a relief to shuck it.
Only the unusual, uneasy feel of the airplane marred the flight, and
not even this dampened our customer’s eagerness to take possession of
the airplane. On investigation we found that the problem was caused
by a minor maladjustment of the SAS system. This was quickly fixed,
and at NASA’s request after this single powered flight we formally
turned X-15 number one over to the customer--lagging five months on
a five-year-old schedule. Captain Richardson forgot my martini that
day, but NASA director Paul Bikle made up for it. At the post-flight
briefing he presented me with a fifth of Old Taylor. Everybody was
quite happy. The time had come to put the black bird to work.
The North American flight-test team then turned its complete
attention to X-15 number two, the plane I had cracked on the November
5 landing. Under our contract terms we had to perform a series of
required demonstration points with the airplane. We would show that
the ship was capable of withstanding heavy G forces in a turn,
pull-up or roll. I would dive the ship from extreme altitude to prove
that it would recover satisfactorily. We would test the ballistic
control system, the jet nozzles on the nose and wing which would be
used later to steer the ship in airless space.
Our first attempt with X-15 number two on February 4 was a dismal
failure, perhaps attributable to “hangar fever.” The plane had not
been in the air for ninety-one days. Everything seemed to go wrong.
The cabin would not pressurize. My radio went out. An APU failed for
the first time in almost a year. The Walc tank-pressure sagged. Even
the jettison was feeble. We landed--the X-15 in its nest under the
B-52 wing--with a great deal of the Lox, Walc, and hydrogen peroxide
still on board.
After one week of intense fixing we got back into the air again on
February 11. We loitered at altitude, simulating the long ride to the
ultimate Utah launch point. The countdown revealed no malfunctions
and, as still another test, I launched myself from the B-52. The
eight barrels of the engine blazed and I zoomed easily to 90,000
feet, almost eighteen miles into the sky. I leveled out, rockets
still blazing, to about 2.5 Mach. At burnout I pushed the ship into a
very steep powerless dive, simulating a re-entry from space to earth.
On Murray’s 1954 altitude flight, the X-1-A had tumbled wildly at
this crucial point, but the X-15 held stable. In the dive my speed
held at Mach 2.0, or 1320 miles an hour. At that speed the desert
floor comes up mighty fast. It took me only twenty seconds to dive
from 90,000 to 55,000 feet--almost seven miles. The ship was a little
slow in the dive recovery. Although I pumped in full “up” stabilizer,
she did not pull out until I reached about 50,000 feet.
Following the dive recovery I made several highly technical
demonstration points. Then because I was curious I popped the dive
brakes at Mach .9. The effect was startling, like hitting a brick
wall. Inadvertently I said “Wow!” over the radio. This set off
Charlie Feltz: “Wha’d he say? Wha’d he say?” On the landing not many
seconds later I caused a little more excitement. I had forgotten to
arm the ballistic charge in the ventral fin. When I pushed the switch
to blow the ventral at 6,000 feet on final, nothing happened. We all
had visions of “the world’s fastest plow” digging a furrow in the
lake bed. I quickly noted my oversight, armed the charge, and blew
the fin before touchdown. On downwind leg before landing, the oxygen
regulator failed and it became extremely difficult to breathe. By the
time the ship stopped I was not able to suck any oxygen at all. But
this was no great emergency. I simply opened the ram-air door and the
visor on my helmet. This flight was considered a whopping success.
We were rolling hard now, and it is difficult to recall the high
points of the individual flights. On February 17 the upper rocket
engine unaccountably shut down halfway through the run and I finished
the demonstration on one engine. We lost a little ground. But on
the March 17 flight I doubled the number of in-flight data points
and regained what we had lost. The ship flew beautifully, so well
that I exclaimed on the radio: “The _best_ airplane I ever flew.” On
the landing I felt so happy that I did a side-slip to lose a little
excess altitude. This well-known maneuver is not recommended in
modern high-performance airplanes, especially in one like the X-15,
but it indicated our complete confidence in the black bird.
Our ground turn-around time was now amazingly brief. In fact on
the very next day, March 18, the crew had the airplane ready again
for flight. About ten seconds before I was to cut myself loose (by
then self-launching was adopted as standard procedure in the North
American operation), my chase pilot, Al White--bless him--noticed a
faint trickle of alcohol pouring out of a drain from the engine bay.
He called out, and I instantly canceled the drop. Alcohol spilling in
the engine bay spelled real potential trouble. If I had dropped and
lighted off the engine, it would probably have exploded. The alcohol
leak was traced to a cracked fitting in the maze of engine plumbing.
On March 25, sixty-two days after we turned X-15 number one over to
NASA, test pilot Joe Walker made his first flight. This time the old
pro, feeling oddly misplaced, flew in a chase plane. Joe took his
time for his first launch. The B-52 made several circles while Joe
held the countdown. But then he cut away cleanly for a brief run.
During the long delay my chase plane ran low on fuel and I had to
return to base. So I missed seeing another man land the X-15 for the
first time. Walker danced a jig on the lake bed to show his elation.
In the next fifty-five days Walker and Air Force pilot Bob White
made five additional powered flights in X-15 number one. This was an
average of about one flight every ten days, a sustained turn-around
time that beat most previous NASA records, except those we had
established with the Skyrocket in the old days. Bob White experienced
little difficulty in his first rocket-powered flight. He did a
beautiful job, in my opinion. On his third flight, May 19, he zoomed
to an altitude of 107,000 feet. Later, on August 12, he reached
136,500 feet.
Walker made additional flights. On his third, May 12, he left all
the rocket barrels on for the entire flight and added half a Mach
number to the highest speed I had achieved in the plane. He reached
almost the limit with the small engines, Mach 3.2, or about 2,110
miles an hour, a world’s speed record. Later, on August 4, he flew
the ship Mach 3.3, 2,196 miles an hour, breaking his own record.
X-15 number one was performing like the champion she was bred to be.
Walker’s speed run was made on X-15 number one’s seventh consecutive
powered flight with no intervening aborts. No experimental airplane
in history--for that matter, very few conventional airplanes--have
operated so well so soon after delivery from the manufacturer. This
pleased us greatly and almost compensated for the year of frustration
we had been through.
On March 29, four days after Joe Walker’s first flight, I took X-15
number two into the air again for additional demonstrations. Most
of these are too complicated to describe in detail. In essence I
subjected the ship to severe strain in a variety of positions and
angles of attack to prove that she would hold together in flight even
under extraordinary circumstances. One of these maneuvers was an
abrupt pull-up which put about six G’s on the ship. The newspapers
made a lot of this flight--the fact that by pulling six G’s I weighed
six times my normal weight, or almost half a ton--but a six-G
maneuver is routine for a fighter pilot. Two days later, on March 31,
I repeated these maneuvers and performed others.
During April we delayed our flight program temporarily to install and
ground-test the ballistic control system. In principle, the little
hydrogen-peroxide jets are quite simple. However, the installation
is complicated. Both the jets and the APUs use the same source of
hydrogen peroxide. Thus it was necessary to establish a careful
balance between the two--meaning more regulator valves and other
devices which leak. Ultimately this installation and test spun into
another around-the-clock routine, with Stormy prodding us to the
limit. By May 5 we were ready.
All the difficulties we feared, plus a few more, took place--just
like the early days. At fifteen minutes to drop I operated the
ballistic-control-system lever with my left hand. When I pushed
the lever to the “up” and “down” positions, the hydrogen peroxide
squirted through the jets in the nose. The system was not designed
for operation at low altitude while the X-15 is cold. Thus when the
undecomposed peroxide from the nose jets sprayed back and struck
the windshield, a thick coating of ice was formed. I was sealed in
blind. No amount of defogging gas helped. During the launch rehearsal
an APU turned erratic and shut itself off. We had not yet achieved
the necessary delicate balance in combining all the systems. This
abortive flight touched off another night-and-day work regime that
went on for about three weeks. We were ready again on May 26.
We took off on schedule. Jack Allavie was flying in the left seat
of the B-52. Fitz Fulton, who had made most of the drops in 1960
as co-pilot, was replaced by Charlie Bock, back for his first
mother-plane flight in seven months. I was in a flippant, cocky mood.
It was my twenty-fifth flight in the X-15. I had never added the
figures but I suppose by then I had spent some forty hours in the air
under the B-52 wing.
I had some additional equipment in the X-15 cockpit that day, a
so-called “physiological package,” the type that will be sent aloft
with the Project Mercury Astronauts when and if they orbit the earth.
I was wired like a chimpanzee, with devices to measure my skin
temperature, rate of breathing, heartbeat, blood pressure--everything
but a “rectal probe,” for reference temperature, and _that_ I
refused to buy. All these devices telemetered a constant flow of
physiological data to a group of aero-medical officers on the
ground. I consider this information rather personal, and it seemed
an indignity to have it broadcast so freely. Besides, I question
its usefulness. The roots of capability are in a man’s spirit--a
difficult measurement to get.
So while we loitered at altitude waiting to launch, I cooked up a
plot to tease the aero-medical officers. For a period of about thirty
seconds I breathed at a heavy rate and wriggled violently in the
cockpit, driving their gauges almost to the limit, I’m sure. Then I
sat rigid--almost yogi-like--and held my breath for a full minute,
during which time the gauges should have sagged to zero. In theory,
I was dead. The aero-medical officers flashed no warning, a subtle
proof that their faith lies in the man, not the equipment. A fine
point can be made here.
A second trick occurred to me. I knew from long experience in
altitude chambers with aero-medical devices that if I flexed my
muscles violently for a few moments it would drive my EKG (heartwave
trace) right through the ceiling. I planned to do this and then
to pull the plug on the “physiological package” telemetering. The
reading on their gauges would be a rapid heart acceleration and then
a total, mysterious blank. I changed my mind about this at the last
minute because I was afraid I might give Charlie Feltz real heart
failure.
The launch--my eleventh in the X-15--was beautiful. For the tenth
time my left hand flicked across the rocket-barrel toggles. My right
hand gripped the sidearm control, which I intended to use throughout
the flight and on the landing. I had not used this control on landing
since the first glide flight. During the early stages I was concerned
that if anything dire happened on landing, it would probably be
blamed on that very fine, but new and controversial, piece of
equipment.
The X-15 zoomed toward the heavens, all eight barrels going wide
open. At 42,000 feet I kicked the rudder and the ship yawed
severely--another demonstration maneuver. I recovered easily and
roared about the sky, turning, twisting, rolling, and spinning like
a bullet, subjecting the plane to unusually heavy strains. My speed
climbed up to Mach 2.7, considerably beyond my Mach 2.0 restriction.
I had let the rocket engines burn a little longer because I needed
the extra power to reach the lake bed. Also the demonstration points
were safer to make at higher speed.
After engine burnout I coasted silently toward the desert lake,
testing the ballistic control system. I squirted the hydrogen
peroxide through the nose jets, calling “nose up” and “nose down”
on the radio. This was simply a test to see whether the system
functioned properly. In the thick atmosphere at 50,000 feet, where
I began the test, the weak nozzles have no effect whatsoever on the
X-15 flight attitude. The North American altitude restriction was
still in force. Thus I could not make the test above 100,000 feet
where a gentle squirt from the jets would considerably change the
airplane attitude. We had corrected the cause of the liquid bath, and
the windshield did not ice over.
I chose a runway and for the eleventh time brought the ship in for
a landing. I used the sidearm control all the way. It is a little
more sensitive than the center-control stick, but with practice I
believe pilots will find it superior to the old-fashioned “ax-handle”
control. The X-15 touched down smoothly, concluding the last flight
with the two smaller engines. It was time to take her to the “barn”
for the big-engine conversion.
With the conclusion of that flight, the box score on both
airplanes was a total of thirty-one flights. A little over half of
these--sixteen, to be precise--were made under rocket power, and one
was the first glide test. These were completed five years almost
to the day from the time Hugh Elkin and his Advanced Design group
at North American first submitted the X-15 conception. This time
was about one year less than it took to design, build, and fly the
Skyrocket, the most successful, after the X-1, of the early era
of rocket airplanes. It was about two years less than the time it
usually takes to design and build a modern jet fighter such as the
F-100. It was about three or four years less than the time it took
to build the hangar-loving X-3. It was five years less time than it
took to build and fly the jinxed X-2 in which Everest, Kincheloe,
and Apt set their world speed and altitude records. Considering that
the X-15 is not only the most advanced aircraft ever conceived by
man, but also a ship designed to fly into the fringes of space, I do
not believe it is immodest to claim that we had pulled off a minor
miracle. We did this in spite of the false starts, frustrations, and
malfunctions, those events that naturally cling to the memory and
upon which I have probably dwelt too long in this account.
* * * * *
About this time a second minor miracle took place in Washington, D.
C. The Congress and the new Secretary of Defense, Thomas S. Gates,
took another look at the gutted B-70 bomber program. Gates announced
publicly that he was ready to “reconsider” the craft as a weapons
system. Then the Congress voted $285 million to restore about half
the original program. There was, of course, no _direct_ connection
between this turnabout and the success of the X-15 flight-test
program. But perhaps in some indirect way the fact that the X-15
had flown like a champion at Mach 3--the B-70 cruising speed--and
routinely to the B-70 cruising altitude of 70,000 feet, influenced
some people to think twice. The restoration of the B-70 now made each
flight of the X-15 more meaningful. The data we collected from the
X-15 would be used to advantage on the B-70.
Actually, I believe, the decision to restore the B-70 was inevitable.
The United States simply could not abandon the manned aircraft
altogether and survive as the pillar of freedom in the West. Now
that wisdom prevailed, we hoped that the powers that be would take a
careful look at the total manned-aircraft spectrum. Our current fleet
of Air Force planes is approaching obsolescence. As yet there is
still no advanced fighter aircraft in the works. In fact, as we look
into the future, the B-70, which may be ready to fly a few years from
now, stands very much alone, a single piece of hardware. Between the
current, aging Air Force fleet and the B-70, amazingly enough, there
is only one craft in existence, the X-15, and only one Air Force
pilot, Bob White, who has ever flown it. Our United States Air Force
should have a thousand rocket pilots. By contrast, the Soviet Union
has never stopped building airplanes. Each year they turn up with
ever-faster fighters and bombers, as well as a force of missiles.
By default, the United States arrived at a point of imbalance that
would be ludicrous if it were not so potentially dangerous. The U. S.
_must_ produce manned aircraft to match the Soviet Union. Missiles
alone are not enough.
As I have said before, bad news usually comes with the good. The B-70
was restored but our efforts to persuade high circles in Washington
that we should capitalize on the X-15 concept and the vast experience
of our construction and flight-test teams for the exploration of
space fell on deaf ears. Within NASA the Project Mercury capsule
dominated. Within the Air Force there was still justifiably much
uncertainty about the use of a space craft for a military mission,
and the effort in that service was restricted largely to paper
studies. Firmly believing that in the conquest of space the nation
would ultimately swing to an X-15 concept--a craft that could go
into space and then return to earth to land with dignity--we pressed
on, proposing a two-seater version of the X-15, a trainer to check
out large numbers of Air Force pilots. We urged manned concepts in
the belief that to rely solely on automatic concepts presupposes a
mathematical certitude not found in war, peace, or the quests of men.
We made few converts.