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Murphy's Law: Whatever Possibly Can Go Wrong, Will

Few know that this famous precept began with USAF engineer, Capt. Ed Murphy. In 1949, he was working at the Aero Medical Research Lab at Wright-Patterson AFB, Ohio, in support of Col. John P. Stapp's expermimental crash research testing at Edwards AFB, California. Frustrated with a malfunctioning piece of equipment, Murphy remarked concerning a technician who had wired it, "If there is any way to do it wrong, he will." The term "Murphy's Law" soon was assigned to the statement.

German Jet Aircraft

Technological advances, many of which were pioneered during WWII, ushered in a new age in the late 1940's despite limited funding for research and development. To take advantage of German scientific advances made during the war, scientists and engineers were recruited from Germany and brought to the United States to work with their American counterparts. In addition, the Rand Corporation, a nonprofit organization, was created to assist the Air Force in selecting the most promising development programs; research projects were awarded to leading educational institutions; an Air Force Scientific Advisory Board was created; and new or existing test facilities were built or improved.

Among the most significant of advances was the continued development of jet-propelled aircraft. However, research in other areas expanded knowledge and developmental capability in many fields including aerial refueling and other new flight techniques, the discovery or creation of new or improved materials, solar observation, nuclear weapons testing, weather studies, and high altitude research. Such efforts also prompted the introduction of a variety of experimental aircraft developed to explore new frontiers in aerodynamics, materials, and expanded performance realms. Research and development activities extended into nearly every aspect of science.

America's first jet aircraft was the Bell P-59 Airacomet, powered by two anemic General Electric engines. Also known as the "Lead Sled," it was no faster than most piston fighters but provided much-needed experience with new engine technology. Security surrounding the P-59 program was such that a fake four-bladed propeller was affixed to the jet's nose when it was towed from the hangar.

Based on original research and European data, the United States began fielding a stable of more capable jet fighters. The first useful design was Lockheed's P-80 Shooting Star, followed by Republic's P/F-84 Thunderjet. Although generally underpowered, they offered a significant combat capability that shortly would be tested in Asian skies.

Between 1949 and 1951, the Air Force test pilot school was moved from Dayton, Ohio, to Edwards Air Force Base, partly because California offered excellent weather year-round. Although the name of the organization changed frequently (it was the Air Materiel Command Test Pilot School in 1949), its mission remained consistent: to provide skilled pilots capable of evaluating new designs and techniques in the military aviation and aerospace fields.

Those were heady days in the high desert, with exciting experimental concepts to be tested as well as a succession of new fighters and other types. The challenge and satisfaction of mastering complex, often dangerous, equipment attracted many of the finest pilots in the Air Force.

The dean of test pilots was Colonel (later Major General) Albert Boyd, an extremely capable flier and leader who oversaw most Air Force test functions during the 1940s and beyond. It was said that from 1945 to 1957, the AAF and U.S. Air Force (USAF) never bought an airplane without his endorsement. Boyd was known as a stern taskmaster but he was also acknowledged as the complete master of his field. The Tennessean had been at Pearl Harbor in 1941 and already enjoyed a reputation as a "can-do" maintenance and engineering officer. Rated in an incredible 25 aircraft types simultaneously, in June 1947 he returned the world speed record to America for the first time in 24 years. Piloting a modified P-80, he recorded a respectable 623 miles per hour in June 1947. When Major General Boyd retired, he had logged an awesome 23,000 military flight hours in hundreds of aircraft types.

In 1947, the Navy and AAF both had progressive flight test programs, "pushing the envelope" of jet- and rocket-powered aircraft. The high desert of Southern California provided a natural airfield, the miles-long Muroc Dry Lake, which seemed designed for high-speed airplanes. A variety of experimental designs was tested at Muroc, which later became part of the complex for Edwards Air Force Base, named for Captain Glenn Edwards, who died testing Northrop's innovative YB-49 "Flying Wing" in 1948. By tradition, AAF and USAF bases were named for dead airmen, leading Brigadier General Chuck Yeager to explain his longevity: "I never let a pathologist examine me and I never let them name an air base after me." They did, however, make an exception and name a street for him.

The Navy's lead program was built around two sexy red Douglas D-558 Skystreaks. They were turbine-powered machines able to take off under their own power, and in August 1947 they established back-to-back speed records of 640 and 650 miles per hour. The program was ready to attempt a Mach One record, but the Navy declined, balking at the $50,000 price per flight.

That left the field wide open to the Air Force. Like the D-558, the Bell X-1 was a straight-wing design, but any similarity ended there. The orange rocket's fuselage was based on the shape of a .50-caliber bullet, and the machine had to be air-launched from a B-29. Nevertheless, it demonstrated excellent potential with a four-chamber, liquid-fuel engine.

Bell began unpowered flights in 1946 with the first use of rocket power before year's end. The AAF took over the project in July 1947 with progressively faster speeds being recorded. The X-1's mission was to explore compressibility effects beyond a conventional jet's Mach .85, pushing ever closer to the "sound barrier." Despite initial doubts that the straight-wing design could punch through the Mach, some pilots and engineers believed it possible. Among them was 24-year-old Captain Charles E. Yeager, previously a Mustang ace, who achieved lasting fame when he flew Glamorous Glennis to 700 miles per hour on October 14, 1947.

Brigadier General Charles E. "Chuck" Yeager (1922- ) Among the most significant airmen of all time, Chuck Yeager seemed to define the indefinable mystique of "the right stuff." He gained notice as an 8th Air Force P-51 pilot in 1943 through 1944, not only as a double ace but as one of the few who bagged a German jet. Although lacking formal education, by persistence and innate ability he established himself in the postwar Air Force as a knowledgeable, analytical test pilot. In 1947, he flew the Bell X-1 to Mach 1, proving the viability of supersonic flight and ensuring his place in history. Six years later he reached Mach 2 as well. During the Vietnam War, Yeager commanded the 405th Fighter Wing, a composite unit flying a variety of aircraft from bases in South Vietnam, Thailand, and Taiwan. Subsequently he served as U.S. Defense Representative to Pakistan, where he used a helicopter to count wrecks of downed aircraft during the 1971 war with India. Yeager continued flying until retirement in 1975, but kept current in tactical jets as a consultant at Edwards Air Force Base. On October 14, 1997, he went supersonic in an F-15 Eagle, half a century after his historic flight in Glamorous Glennis.

Like most military pilots, Chuck Yeager knew how to have a good time. The night before his flight into history, he had taken a nasty spill while horse racing with his wife, wrenching a shoulder and cracking two ribs. However, he was not about to let such inconvenient developments keep him out of the X-1. A doctor taped his ribs, so "the pain was at least manageable."

Before takeoff Yeager confided in his fellow test pilot, Jack Ridley, concerned that his injuries would prevent him from closing the high-tension lock on the X-1s canopy. Ridley's solution was inspired. He sawed off a broom handle and suggested that Yeager use it as a lever for more mechanical advantage on the canopy. It worked like a charm.

After release from the B-29, Yeager rode the rocket to 42,000 feet, indicating .96 Mach with three chambers firing. He found that the faster he flew, the smoother the ride. "Suddenly the Mach needle began to fluctuate," he related. "It went up to .965 Mach - then tipped right off the scale. I thought I was seeing things! We were flying supersonic! It was as smooth as a baby's bottom: Grandma could be sitting up there sipping lemonade." He maintained supersonic speed for about 20 seconds, and then raised the nose to decelerate.

Yeager radioed Jack Ridley, saying that the meter had been pegged. Ridley replied that Yeager must be seeing things. Characteristically unconcerned, Yeager allowed that he was still wearing his ears, and nothing fell off the airplane. On the ground, the National Advisory Council on Aeronautics (NACA) monitoring crew reported distant thunder. It was the sound of the future: a man-made sonic boom. Data showed that Yeager had pushed Glrrvnoi-ous Glennis to 1.07 times the speed of sound.

Yeager's feat was kept secret for a time, but word leaked out and the Air Force publicly acknowledged the record. Eventually, the X-1 achieved 967 miles per hour and reached 73,000 feet.

In late 1953, Yeager flew the upgraded X-1A to 1,650 miles per hour, becoming the first pilot to achieve Mach 2 as well. Neither X-1 variant had an ejection seat, and at typical speeds a conventional bailout was almost impossible-proof of the courage and dedication of the test pilots involved.

Other X planes followed through the 1950s into the 1960s. The X-2 further "pushed the envelope" of supersonic flight, gaining additional knowledge of structures, materials and heat, flight control, and propulsion. Among the record setters was Captain Frank "Pete" Everest, an erstwhile P-40 pilot, who logged Mach 2.87 (1,900 miles per hour) in July 1956.

After a breakfast of eggnog and toast, Everest climbed into the B-50 mother ship and rode it to 33,000 feet. There he eased himself into the X-2's cramped cockpit, completed his checklist, and waited while the Boeing gained speed in a 3,000-foot descent. Then the rocket plane was dropped.

Everest fired both chambers of the rocket engine, which ignited with such force that he was slammed back against his seat, his helmet striking the cockpit wall. He shook his head to clear the shock of sudden acceleration, and then slowly pulled the stick back to begin his climb for more altitude. Trying to maintain his planned climb schedule, Everest found the X-2 seemingly running away from him. Fighting the controls, struggling to hold a steady flight path, he was already supersonic.

Pete Everest watched the Mach meter climb to a speed that he knew had never been seen before. Still in level flight, the rocket continued the astonishing momentum of its climb. Telemetry proved that his top speed was more than 1,900 miles per hour. Subsequently, Everest wrote that he felt like an explorer, like Columbus and Magellan. He felt "both awed and proud." Eventually the X-2 became the first plane to achieve Mach 3 (2,094 miles per hour).

The Air Force and the National Air and Space Administration (NASA) combined on the ultimate X plane, the X-15, which (in Star Trek terms) literally went where no man had gone before. With a design specification of 4,000 miles per hour and more than 50 miles altitude, it was unlike anything else. The builder, North American, teamed with the Air Force, Navy, and NASA to produce a succession of spectacular flights during 1961, increasing speed from Mach 4 to Mach 6 that year alone. Air Force Captain Pete Knight capped the program with his October 1967 record of 6.7 times the speed of sound.

Walter J. Boyne, USAF (ret.) Series Editor, Barrett Tillman. The Jet Age. Alpha Bravo Delta Guide to the U.S. Air Force. Alpha Books. 2003.

Hypersonic! The Story of the North American X-15 Nineteen years before Space Shuttle, the small, black, rocket-powered, bullet-shaped X-15 showed it was possible to fly into - and out of - space. At the dawn of the 21st Century there seem to be a great interest in hypersonic flight. For the most part this is related to a new generation of missiles - air-to-air and air-to-surface - that are being proposed as the next logical increment in weapons, although the designers of the forever-in-development replacement for the Space Shuttle also have a vested interest in hypersonic research.

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