© 1998 Antelope Valley Press, Palmdale, California, USA (805) 273-2700
What he didn't know as the aircraft sped to 1,291 mph was that he and the Skyrocket pilots who followed were setting speed benchmarks that would still stand for military and civilian aircraft four decades later.
Crossfield, Stanley P. Butchart, Robert A. Champine, and John Griffith, all pilots of both the D558 I Skystreak and the doublesonic D-558 II Skyrocket, recalled their experiences in a symposium at the Lancaster Performing Arts Center Tuesday.
The event commemorated the 50th anniversary of the first flight of the D-558 aircraft series by Douglas Aircraft Inc. test pilot John Martin.
Joining the four pilots were Air Force historian Richard Hallion, and moderator and NASA Dryden Flight Research Center SR-71 research pilot Ed Schneider.
More than 175 people attended the event sponsored by Dryden. NASA's predecessor, the National Advisory Committee for Aeronautics, and the Navy handled flight research on the D-558 I Skystreak and D-558 II Skyrocket at Edwards AFB.
"I never thought Mach 2 would be so big," Butchart said.
Champine said he just enjoyed the ride:
"Each day was more fun. I was glad to be there and be smart enough to do the job without killing myself," he said.
Crossfield said he was too busy to think about the accomplishment until his later design, construction and test work on the X-15.
The climate
The 1940s were a complex era in aviation, explained Air Force Historian Richard Hallion.
Turbojet engines were pushing aircraft to about 500 mph, but knowledge was limited on causes of breakup when aircraft approached Mach 1.
Flight research also became vitally important to serve growing national security needs as the transition began from World War II to the Cold War, Hallion said.
After then-Capt. Chuck Yeager broke the sound barrier in Oct. 14, 1947, in the Bell X-1, the Douglas D-558 I Skystreak complemented the research. The X-1 was exploring the supersonic region and the Skystreak had superior cruise speeds and handling in the transonic region approaching Mach 1.
Tight fit
D-558 series aircraft flew well, but Champine said at high speeds the aircraft shook violently and the cockpit was small.
"It was such a tight fit, the paint on the helmet would rub off on the Plexiglas," he said.
The paint-transfer interfered with the pilot's vision and no one realized immediately why streaks appeared on the canopy.
"After landing, the only thing I could do was make a helmet cover with a chamois cloth. It worked," he said.
Butchart agreed the experimental aircraft was confined.
"It was like a kiddie-car. It was 22 inches wide, and if you turned to look at the tail, you could get your helmet stuck," he said. "There isn't a one of us that could fit in it now."
Hallion said Douglas nicknamed the jet-propelled dash-one model "the crimson test tube" because engineers took the smallest plane possible and wrapped it around the biggest engine - the TG-180 that evolved into the J-35.
Approaching Mach 1
The goal of Mach 1 was to defeat air compressibility on the aircraft that was causing breakups of many planes as pilots approached the dreaded sound barrier.
"I saw a P-51 go into a dive and it hit the ground so hard it buried the engine 30 feet in the ground," Griffith said.
He also felt the compressibility factors when he flew.
"I was in a P-40 at 32,000 and the stick felt like it was in two feet of concrete," he said.
D-558 research
Both the Bell X-1 and the Douglas D-558-I started in 1944.
Bell was committed to a straight wing for the X-1 and designers also didn't want any other variables on the aircraft designed to break the sound barrier, Hallion said.
Meanwhile, Douglas and the Navy decided to end the D-558 I Skystreak at three models and make three more with swept wings, called the D-558 II Skyrocket.
The Skystreak defined flight in the realms just above and below the speed of sound. But the faster Skyrocket helped to write the book on what was known about swept wings at the time, Hallion said.
Skyrockets were designed for 1.5 Mach, but by using certain flying techniques, it was possible to exceed Mach 2 without the instabilities some pilots encountered at about Mach 1.5, Crossfield said.
Hallion said although the D-558 II was conceived as a land-based aircraft, researchers learned it would have greater flight safety and an ability to achieve higher Mach numbers if launched from the air.
Crossfield said another contribution of the D-558 II program was the infancy of full-pressure flight suits that later evolved for the X15 and space program.
"One of the parts was a sevendollar Gas Company gauge. The government would never allow that part to be used today," he said.
Control
Comparing flight research sophistication then and now, Butchart said the equivalent of today's mission control room full of people was, at that time, basically the guys in B-29s calling the shots.
Once a green light flashed on the bomber flight deck, the B-29 pilot knew the D-558 II pilot was ready. Sometimes it would take an hour after the green light to get to altitude, especially when Crossfield flew because he asked the pilot to reach the highest possible altitude, Butchart said.
If anything went wrong, higher was safer. And sometimes things went wrong.
Butchart recalled the day in March 1956 when the D-558 II and its pilot narrowly escaped disaster.
The B-29, flying at 31,000 feet with the Skyrocket nestled in its belly, had an engine failure. And it got worse. A second engine exploded, sending shrapnel into the hull of the B-29 and into the space where the Skyrocket was suspended just moments before the explosion.
Fortunately, test pilot Jack McKay released the Skyrocket from the mother ship just prior to the explosion. Otherwise, both he and the D-558 II would have likely perished.
Rough day
Butchart recalled that when he first arrived in 1951, he didn't have experience flying twin-engine aircraft. He then flew a C-45 cargo aircraft and several months later he flew a B-29. After a few more flights, Butchart was told he was a B-29 pilot.
"The B-29 was a miserable airplane. No respectable fighter pilot would fly it," Crossfield joked.
Crossfield said his worst day as a pilot was at the controls of a B-29 with Butchart.
The B-29 blew an engine and Crossfield executed a maneuver which flipped the aircraft on its back, causing an immediate screaming dive, he said.
After Crossfield recovered the aircraft from the potentially fatal dive, he asked Butchart, "Why did you let me do that maneuver?"
The reply: "You're flying."