Boeing P2B-1S, Bu. No. 84029, at Edwards AFB, 22 March 1956. (NASA)
22 March 1956: While carrying the U.S. Navy’s Douglas D-558-II Skyrocket, problems developed aboard both the research rocketplane and the “mothership.” The modified four-engine heavy bomber, a U.S. Air Force Boeing B-29-95-BW Superfortress 45-21787 (which had been transferred to the U.S. Navy 5 May 1947 and redesignated P2B-1S Superfortress), had a runaway propeller on the Number 4 engine, outboard on the right wing. The propeller broke apart from excessive rotational speed, slicing through the Number 3 engine, the fuselage, and striking the Number 2 engine.
Douglas D-558-II Skyrocket, Bu. No., 37974, NACA 144, is dropped from the Boeing P2B-1S Superfortress, Bu. No. 84029, NACA 137. (NASA)
NACA research test pilot John Barron (“Jack”) MacKay, in the cockpit of the Skyrocket, had called “No drop!” because of problems with the rocketplane, but he was jettisoned so that the mothership could maintain flight and make an emergency landing.
McKay dumped the Skyrocket’s propellants and glided to the lake bed.
John Barron McKay, NACA/NASA Research Test Pilot. (NASA)
“Each rocket-plane pilot had worked out, in conjunction with the pilot of the mother ship, a procedure to follow if any emergency developed in either plane. Jack McKay, who had developed into a very able test pilot, and I had agreed with Butchart that if something went wrong after either of us had entered the cockpit of the Skyrocket and had closed the canopy, he would immediately jettison the rocket plane, leaving the rocket-plane pilot to look after his own hide. As a matter of fact, McKay and Butchart later ran into such an emergency. One day something went haywire in a propeller on the B-29 mother plane. As agreed, Butchart instantly cut loose the Skyrocket. A split second later the B-29 prop tore loose and cartwheeled through the space the Skyrocket had just vacated. McKay landed without difficulty; but had Butchart not cut the parasite plane loose, the prop would have ripped into its fuel tanks, causing an explosion that would have killed everyone, including McKay.”
— 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 21 at Pages 201–202.
The Superfortress pilots, Stanley Paul Butchart and Neil Alden Armstrong, landed the plane safely on the lake bed at Edwards Air Force Base.
Neil Armstrong would land on The Moon 13 years later.
The P2B-1S is jacked up inside a hangar at Edwards AFB so the the Douglas D-558-II Skyrocket can be loaded aboard. (NASA)
The National Advisory Committee for Aeronautics took over P2B-1S Bu. No. 84029 from the U.S. Navy 27 August 1951, and designated it NACA 137. It was retired and placed in storage at NAS Litchfield Park, Arizona, 5 August 1959. NACA sold it to Allied Aircraft Sales, and it received the civilian registration N91329. It was next sold to Ralph W. and Stephen Johnson’s American Air Museum in Oakland, California. The bomber was restored to the B-29 configuration, including gun turrets. It is now in the Kermit Weeks’ Fantasy of Flight collection near Polk City, Florida, with FAA registration N29KW.
William Barton Bridgeman (Boris Artzybasheff/TIME Magazine)
15 August 1951: Just 8 days after he set an unofficial world speed record of Mach 1.88 (1,245 miles per hour; 2,033.63 kilometers per hour), Douglas Aircraft Company test pilot William Barton (“Bill”) Bridgeman flew the rocket-powered United States Navy/National Advisory Committee on Aeronautics (NACA) Douglas D-558-II Skyrocket, Bu. No. 37974, to a world record altitude at Edwards Air Force Base in the high desert of Southern California.
The Skyrocket was airdropped at 34,000 feet (10,363 meters) from a highly-modified U.S. Navy P2B-1S Superfortress, Bu. No. 84029. The mother ship was a U.S. Air Force Boeing B-29-95-BW Superfortress, 45-21787, transferred to the Navy and flown by another Douglas test pilot, George R. Jansen.
Douglas D-558-II Skyrocket, Bu. No., 37974, NACA 144, is dropped from the Boeing P2B-1S Superfortress, Bu. No. 84029, NACA 137. (NASA)
The flight plan was for Bridgeman to fire the rocket engine and allow the Skyrocket to accelerate to 0.85 Mach while climbing. The Skyrocket was powered by a Reaction Motors LR8-RM-6 engine, which produced 6,000 pounds of thrust. As the rocketplane continued to accelerate to Mach 1.12, the test pilot was to pull up, increasing the angle of climb while holding an acceleration rate of 1.2 Gs. This would result in a constantly increasing angle of climb. When it reached 50°, Bridgeman was to maintain that, climbing and accelerating, until the rocket engine ran out of fuel.
Initially, the plan was to continue climbing after engine shutdown until the D-558-II was approaching stall at the highest altitude it could reach while on a ballistic trajectory. There were differing expert opinions as to how it would behave in the ever thinner atmosphere. On the morning of the flight, Douglas’ Chief Engineer, Ed Heinemann, ordered that Bridgeman push over immediately when the engine stopped.
Bill Bridgeman stuck to the engineers’ flight plan. As the Skyrocket accelerated through 63,000 feet (19,200 meters), it started to roll to the left. He countered with aileron input, but control was diminishing in the thin air. The next time it began there was no response to the ailerons. Bridgeman found that he had to lower the Skyrocket’s nose until it responded, then he was able to increase the pitch angle again. At 70,000 feet (21,336 meters), travelling Mach 1.4, he decided he had to decrease the pitch angle or lose control. Finally at 76,000 feet (23,165 meters), the engine stopped. Following Heinemann’s order, Bridgeman pushed the nose down and the D-558-II went over the top of its arc at just 0.5 G.
Bill Bridgeman. (Unattributed)
“In the arc she picks up a couple of thousand feet. The altimeter stops its steady reeling and swings sickly around 80,000 feet. The altitude is too extreme for the instrument to function.
“Eighty thousand feet. It is intensely bright outside; the contrast of the dark shadows in the cockpit is extreme and strange. It is so dark lower in the cockpit that I cannot read the instruments sunk low on the panel. The dials on top, in the light, are vividly apparent. There seems to be no reflection. It is all black or white, apparent or non-apparent. No half-tones. It is a pure, immaculate world here.
“She levels off silently. I roll right and there it is. Out of the tiny windows slits there is the earth, wiped clean of civilization, a vast relief map with papier-mâché mountains and mirrored lakes and seas. . . .
“It is as if I am the only living thing connected to this totally strange, uninhabited planet 15 miles below me. The plane that carries me and I are one and alone.”
—The Lonely Sky,William Bridgeman with Jacqueline Hazard, Castle and Company LTD, London, 1956, Chapter XXII at Page 268.
After the data was analyzed, it was determined that William Bridgeman and the Douglas Skyrocket had climbed to 79,494 feet (24,230 meters), higher than any man had gone before. This was the last flight that would be made with a Douglas test pilot. The rocketplane was turned over to NACA, which would assign it the number NACA 144.
A Douglas D-558-II Skyrocket, Bu. No. 37974, glides back toward Rogers Dry Lake at Edwards Air Force Base. A North American Aviation F-86E-1-NA Sabre, 50-606, flies chase. Lieutenant Colonel Frank K. “Pete” Everest and Major Charles E. “Chuck” Yeager frequently flew as chase pilots for both Bill Bridgeman and Scott Crossfield. (NASA)
Bill Bridgeman had been a Naval Aviator during World War II, flying the Consolidated PBY Catalina and PB4Y (B-24) Liberator long range bombers with Bombing Squadron 109 (VB-109), “The Reluctant Raiders.” Bridgeman stayed in the Navy for two years after the war, then he flew for Trans-Pacific Air Lines in the Hawaiian Islands and Pacific Southwest Airlines in San Francisco, before joining Douglas Aircraft Co. as a production test pilot, testing new AD Skyraiders as they came off the assembly line at El Segundo, California. He soon was asked to take over test flying the D-558-2 Skyrocket test program at Muroc Air Force Base.
The D-558-II Skyrocket was Phase II of a planned three phase experimental flight program. It was designed to investigate flight in the transonic and supersonic range. It was 46 feet, 9 inches (14.249 meters) long with a 25 foot (7.62 meter) wing span. The wings were swept back to a 35° angle. The Skyrocket was powered by a Westinghouse J34-WE-40 11-stage axial-flow turbojet engine, producing 3,000 pounds of thrust, and a Reaction Motors LR8-RM-6 four-chamber rocket engine, which produced 6,000 pounds of thrust. The rocket engine burned alcohol and liquid oxygen.
There were three D-558-2 Skyrockets. Between 4 February 1948 and 28 August 1956, they made a total of 313 flights. Bill Bridgeman’s speed and altitude record-setting Skyrocket, Bu. No. 37974, NACA 144, is in the collection of the Smithsonian Institution National Air and Space Museum.
Douglas D-558-2 Skyrocket, Bu. No. 37974, NACA 144. (NASA)
William Barton Bridgeman. (Boris Artzybasheff/TIME Magazine)
7 August 1951: Douglas Aircraft Company test pilot William Barton Bridgeman flew the rocket-powered U.S. Navy/NACA/Douglas D-558-2 Skyrocket, Bu. No. 37974 (NACA 144), to a record speed of Mach 1.88 (1,245 miles per hour/2,034 kilometers per hour) at Muroc Dry Lake (later Edwards Air Force Base) in the high desert of southern California.
The D-558-2 was airdropped at 34,000 feet (10,363 meters) from a Navy P2B-1S Superfortress, Bu. No. 84029 (a U.S. Air Force Boeing B-29-95-BW Superfortress, 45-21787, transferred to the Navy and heavily modified as a drop ship) flown by another Douglas test pilot, George Jansen.
Douglas D-558-II Skyrocket, Bu. No., 37974, NACA 144, is dropped from the Boeing P2B-1S Superfortress, Bu. No. 84029, NACA 137. (NASA)
In his autobiography, Bridgeman described the flight:
We are at 34,000 feet. My cue. Ten cold minutes preparing the ship for flight. The trap door springs and releases the captive Skyrocket swollen with explosive propellants. She blasts into flight.
Thirty seconds and I am supersonic. Sixty-eight thousand feet and this is it. Over the rim. Easy. The electrically controlled stabilizer flies her now. It takes over for me. At .6 G I push over just enough to get my speed. I am on the ragged edge between .6 G and .8 G. It is working! Everything is going according to my plan. It is so easy this time. Surely I cannot be breaking my last record without having to pay for it. The Machmeter is moving up, fluttering toward the Number 2. . . the rockets sputter and the fuel is gone. That’s all she wrote.
Late that afternoon the official speed attained by the Skyrocket reduced from data and film came out of the aerodynamicists’ office. Mach 1.88.
—The Lonely Sky, William Bridgeman, Castle and Company LTD, London, 1956, Chapter XXII at Page 260.
NACA 144, a Douglas D-558-II Skyrocket, Bu. No. 37974, parked on Muroc Dry Lake. (NACA E-1441)
Bill Bridgeman had been a Naval Aviator during World War II, flying the Consolidated PBY Catalina and PB4Y (B-24) Liberator long range bombers with Bombing Squadron 109 (VB-109), “The Reluctant Raiders.” Bridgeman stayed in the Navy for two years after the end of the war, then he flew for Trans-Pacific Air Lines in the Hawaiian Islands and Southwest Airlines in San Francisco, before joining the Douglas Aircraft Company as a production test pilot. He flew new AD Skyraiders as they came off the assembly line at El Segundo, California. Bridgeman soon was asked to take over test flying the D-558-2 Skyrocket test program at Muroc Air Force Base.
The D-558-II Skyrocket was Phase II of a planned three phase experimental flight program. It was designed to investigate flight in the transonic and supersonic range. It was 46 feet, 9 inches (14.249 meters) long with a 25 foot (7.62 meter) wing span. The wings were swept back to a 35° angle. The Skyrocket was powered by a Westinghouse J34-WE-40 11-stage axial-flow turbojet engine, producing 3,000 pounds of thrust, and a Reaction Motors LR8-RM-6 four-chamber rocket engine, which produced 6,000 pounds of thrust. The rocket engine burned alcohol and liquid oxygen.
There were three D-558-2 Skyrockets. Between 4 February 1948 and 28 August 1956, they made a total of 313 flights. The Skyrocket flown by Bill Bridgeman to Mach 1.88 is in the collection of the Smithsonian Institution National Air and Space Museum.
NACA 144, a Douglas D-558-II Skyrocket, on display at the National Mall Building, Smithsonian Institution. (NASM)
