Rocketplane | This Day in Aviation

Scott Crossfield prepares for a flight in the North American Aviation X-15A.

8 June 1959: At Edwards Air Force Base, California, North American Aviation’s Chief Engineering Test Pilot, A. Scott Crossfield, made the first flight of the X-15A hypersonic research rocketplane.

56-6670 was the first of three X-15s built for the U.S. Air Force and NASA. It was airdropped from a Boeing NB-52A Stratofortress, 52-003, at 37,550 feet (11,445 meters) over Rosamond Dry Lake at 08:38:40 a.m, Pacific Daylight Time.

This was an unpowered glide flight to check the flying characteristics and aircraft systems, so there were no propellants or oxidizers aboard, other than hydrogen peroxide which powered the pumps and generators.

The aircraft reached 0.79 Mach (522 miles per hour, 840 kilometers per hour) during the 4 minute, 56.6 second flight.

North American Aviation Chief Engineering Test Pilot Albert Scott Crossfield in the cockpit of X-15A 56-670 before a flight. (NASA) — North American Aviation Chief Engineering Test Pilot Albert Scott Crossfield in the cockpit of an X-15 before a flight. (LIFE Magazine via Jet Pilot Overseas)

In his autobiography, Scott Crossfield described the first flight:

“Three” . . . “Two” . . . “One” . . .

“DROP”

Inside the streamlined pylon, a hydraulic ram disengaged the three heavy shackles from the upper fuselage of the X-15. They were so arranged that all released simultaneously, and if one failed they all failed. The impact of the release was clearly audible in the X-15 cockpit. I heard a loud “kerchunk.”

X-15A 56-6670 under the wing of NB-52A 52-003 at high altitude. Scott Crossfield is in the cockpit of the rocketplane. Air Force Flight Test Center History Office, U.S. Air Force) — X-15A 56-6670 under the wing of NB-52A 52-003 at high altitude. Scott Crossfield is in the cockpit of the rocketplane. (Air Force Flight Test Center History Office, U.S. Air Force)

The X-15 hung in its familiar place beneath the pylon for a split second. Then the nose dipped sharply down and to the right more rapidly than I had anticipated. The B-52, so long my constant companion, was gone. The X-15 and I were alone in the air and flying 500 miles an hour. In less than five minutes I would be on the ground. . . .

There was much to do in the first hundred seconds of flight. First I had to get the “feel” of the airplane, to make certain it was trimmed out for landing just as any pilot trims an airplane after take-off or . . . when dwindling fuel shifts the center of gravity. Then I had to pull the nose up, with and without flaps, to feel out the stall characteristics, so that I would know how she might behave at touchdown speeds . . . My altimeter unwound dizzily: from 24,000 to 13,000 feet in less than forty seconds. . . .

X-15A 56-6670 drops from the wing of the B-52 mothership. This is a glide flight as there is no frost from cryogenic propellants showing of the fuselage. The vapor trail is from hydrogen peroxide that powers the aircraft power systems. Note the roll to the right as the X-15 drops from the pylon. (NASA) — X-15A 56-6670 drops from the wing of the B-52 mothership, 8 June 1959. The vapor trail is from venting hydrogen peroxide used to power the aircraft pumps and generators. Note the roll to the right as the X-15 drops away from the Stratofortress. (NASA)

The desert was coming up fast. At 600 feet altitude I flared out. . . .

In the next second without warning the nose of the X-15 pitched up sharply. It was a maneuver that had not been predicted by the computers, an uncharted area which the X-15 was designed to explore. I was frankly caught off guard. Quickly I applied corrective elevator control.

The nose went down sharply. But instead of leveling out, it tucked down. I applied reverse control. The nose came up but much too far. Now the nose was rising and falling like a skiff in a heavy sea. Although I was putting in maximum control I could not subdue the motions. The X-15 was porpoising wildly, sinking toward the desert at 200 miles an hour. I would have to land at the bottom of an oscillation, timed perfectly; otherwise, I knew, I would break the bird. I lowered the flaps and the gear. . . .

. . . With the next dip I had one last chance and flared again to ease the descent. At that moment the rear skids caught on the desert floor and the nose slammed over, cushioned by the nose wheel. The X-15 skidded 5,000 feet across the lake, throwing up an enormous rooster tail of dust. . . .

—Always Another Dawn: The Story of a Rocket Test Pilot, by A. Scott Crossfield and Clay Blair, Jr., The World Publishing Company, Cleveland and New York, 1960, Chapter 37 at Pages 338–342.

This photograph shows the second North American Aviation X-15A, 56-6671, flaring to land on Rogers Dry Lake, Edwards Air Force Base, California The rear skids are just touching down. The white patches on the aircraft's belly is frost from residual cryogenic propellants remaining in its tanks. (U.S. Air Force) — This photograph shows the second North American Aviation X-15A, 56-6671, flaring to land on Rogers Dry Lake, Edwards Air Force Base, California. The rear skids are just touching down. The white patches on the aircraft’s belly are frost from residual cryogenic propellants remaining in its tanks after a powered flight. (U.S. Air Force)

Before the drop, it was discovered that the aircraft’s Stability Augmentation System was inoperative in pitch mode. During the flight it was found that the hydraulic-assisted flight control system was responding too slowly to Crossfield’s inputs. Engineers analyzed the problem and increased the hydraulic system pressure. The problem never recurred.

Scott Crossfield was the world’s most experienced rocketplane pilot with 82 rocketplane flights before the X-15 program. “. . . he was intimately involved in the design of the aircraft and contributed immensely to the success of the design.”

—At The Edge Of Space, by Milton O. Thompson, Smithsonian Institution Press, 1992, Introduction, at Page 3.

North American Aviation X-15A 56-6670 made the first glide flight and the first and last powered flights of the X-15 Program. It made a total of 82 of the 199 X-15 flights. 56-6670 is in the collection of National Air and Space Museum at Washington, D.C.

A. Scott Crossfield, wearing a David Clark Co. XMC-2 full-pressure suit, which he helped to design and test, with the first of three North American X-15s, 56-6670. (North American Aviation, Inc.)

Major Arthur Warren "Kit" Murray, U.S. Air Force, with the Bell X-1A at Edwards AFB, 20 July 1954. Major Murray is wearing a David Clark Co. T-1 capstan-type partial-pressure suit with a K-1 helmet. (NASA) — Major Arthur Warren “Kit” Murray, U.S. Air Force, with the Bell X-1A at Edwards AFB, 20 July 1954. Major Murray is wearing a David Clark Co. T-1 capstan-type partial-pressure suit with a K-1 helmet. (NASA)

4 June 1954: at Edwards Air Force Base, California, Major Arthur W. “Kit” Murray flew the experimental Bell X-1A research rocketplane to an altitude of 89,810 feet (27,374 meters). He flew high enough that the sky darkened and he was able to see the curvature of the Earth. Newspapers called him “America’s first space pilot.”

The X-1A reached Mach 1.97. Encountering the same inertial coupling instability as had Chuck Yeager, 20 November 1953, though at a lower speed, the X-1A tumbled out of control. The rocket plane lost over 20,000 feet (6,100 meters) altitude before Murray could regain control. For this accomplishment, Major Murray was awarded the Distinguished Flying Cross.

One week earlier, 28 May 1954, Murray had flown the X-1A to an unofficial world record altitude of 90,440 feet (27,566 meters).

Arthur Warren Murray was born at Cresson, Cambria County, Pennsylvania, 26 December 1918. He was the first of two children of Charles Chester Murray, a clerk, and Elsie Espy Murray.

Arthur Murray attended Huntingdon High School, Huntingdon, Pennsylvania, graduating 4 June 1936, and then studied Juniata College, also in Huntingdon, 1937–1938.

Arthur Murray, 1938. (The Nineteen Thirty-Seven Alfarata)

Kit Murray enlisted in the Field Artillery, Pennsylvania National Guard, 17 November 1939. (Some sources state that he served in the U.S. Cavalry.) Murray had brown hair and blue eyes, was 5 feet, 10 inches (1.78 meters) tall and weighed 150 pounds (68 kilograms). Following the United States’ entry into World War II, Sergeant Murray requested to be trained as a pilot. He was appointed a flight officer (a warrant officer rank), Army of the United States, on 5 December 1942. On 15 October 1943 Flight Officer Murray received a battlefield promotion to the commissioned rank of second lieutenant, A.U.S.

Between 6 January and 22 October 1943, Murray flew over 50 combat missions in the Curtiss-Wright P-40 Warhawk across North Africa. After about ten months in the Mediterranean Theater, he returned to the United States, assigned as an instructor flying the Republic P-47 Thunderbolt fighter bomber, stationed at Bradley Field, Hartford, Connecticut.

Republic P-47 Thunderbolts at Bradley Field, Connecticut, 9 September 1944. (U.S. Air Force)

Lieutenant Murray married Miss Elizabeth Anne Strelic, who had immigrated from Czechoslovakia with her family as an infant, at Atlantic City, New Jersey, 29 December 1943. They would have six children, and foster a seventh. They later divorced. (Mrs. Murray died in 1980.)

Lieutenant and Mrs. Arthur W. Murray, 1943. (Murray Family Collection)

Murray was promoted to 1st lieutenant, A.U.S., 8 August 1944. His next assignment was as a maintenance officer. He was sent to Maintenance Engineering School at Chanute Field, Rantoul, Illinois, and from there to the Flight Test School at Wright Field, Dayton, Ohio.

Murray was the first test pilot to be permanently assigned to Muroc Army Air Field (later, Edwards Air Force Base). Other test pilots, such as Captain Chuck Yeager, were assigned to Wright Field and traveled to Muroc as necessary.

Murray’s A.U.S. commission was converted to first lieutenant, Air Corps, United States Army, on 19 June 1947, with date of rank retroactive to 15 October 1946. The U.S. Air Force became a separate military service in 1947, and Lieutenant Murray became an officer in the new service.

Major Arthur Warren (“Kit”) Murray, United States Air Force, with a Northrop F-89 Scorpion interceptor, 1954. (The New York Times)

Murray was involved in testing new Air Force fighters such as the Bell P-59 Airacomet, Lockheed P-80 Shooting Star, Republic P-84 Thunderjet, McDonnell XF-88 Voodoo; and the Douglas XB-43 Jetmaster and North American Aviation B-45 Tornado jet bombers. He also flew the experimental aircraft such as the X-1A, X-1B, X-4 and X-5. Murray spent six years at Edwards before going on to other assignments.

Colonel Arthur Warren (“Kit”) Murray, U.S. Air Force.

Later, 1958–1960, Major Murray was the U.S. Air Force project officer for the North American Aviation X-15 hypersonic research rocketplane at Wright Field.

Colonel Murray retired from the U.S. Air Force in 1961. He next worked for Boeing in Seattle, Washington, from 1961 to 1969, and then Bell Helicopter in Texas.

On 4 April 1975, Kit Murray married his second wife, Ms. Ann Tackitt Humphreys, an interior decorator, in Tarrant County, Texas.

Colonel Arthur Warren Murray, United States Air Force (Retired), died at West, Texas, 25 July 2011, at the age of 92 years.

NASA 800, a highly modified Boeing B-29 Superfortress, carries the Bell X-1A to altitude over Edwards AFB. (NASA) — A highly modified Boeing B-29 Superfortress carries the Bell X-1A to altitude over Edwards AFB. (U.S. Air Force)

The Bell X-1A was a follow-on project to the earlier X-1. It was designed and built by the Bell Aircraft Corporation at Buffalo, New York, to investigate speeds above Mach 2 and altitudes above 90,000 feet (27,432 meters). It was carried to altitude by a modified Boeing B-29 Superfortress, then dropped for the research flight.

The rocketplane was 35 feet, 7 inches (10.846 meters) long with a wingspan of 28 feet (8.534 meters) and overall height of 10 feet, 8 inches (3.251 meters). It had an empty weight of 6,880 pounds (3,120.7 kilograms) and gross weight of 16,487 pounds (7,478.3 kilograms).

The X-1A was powered by a Reaction Motors XLR-11-RM-5 four-chamber rocket engine which produced 6,000 pounds of thrust. It had a maximum speed of Mach 2.44 (Yeager) and reached an altitude of 90,440 feet (27,566.1 meters) (Murray).

The X-1A was destroyed by an internal explosion, 20 July 1955.

This Day in Aviation

Important Dates in Aviation History

Tag Archives: Rocketplane

8 June 1959, 16:38:40 GMT

4 June 1954