4 August 1960: NASA research test pilot Joseph Albert Walker set an unofficial world speed record when he flew the number one North American Aviation X-15, 56-6670, to 2,195 miles per hour (3,532.5 kilometers per hour). This was the 18th flight of the X-15 Program. It was 56-6670’s eighth flight and Walker’s fourth X-15 flight. The purpose of this test was to gradually increase the rocket plane’s speed toward its design limit.
Airdropped from the Boeing NB-52A Stratofortress mothership, 52-003, over Silver Lake, near the California-Nevada border, at 08:59:13.0 a.m., PDT, Walker fired the X-15’s two Reaction Motors XLR11-RM-13 rocket engines for 264.2 seconds. The X-15 accelerated to Mach 3.31 and climbed to a peak altitude of 78,112 feet (23,809.5 meters). [The two XLR11s were used as an interim powerplant until the Reaction Motors XLR99 was ready. The combined thrust of both LR11s was only slightly more than the idle thrust of the XLR99.]
Walker touched down on Rogers Dry Lake at Edwards Air Force Base, California, after a flight of 10 minutes, 22.6 seconds.
4 August 1950: During the Battle of the Pusan Perimeter, wounded soldiers were evacuated from the battlefield by helicopter for the first time when a Sikorsky H-5F of Detachment F, 3rd Air Rescue Squadron, United States Air Force, flew out PFC Claude C. Crest, Jr., U.S. Army, from the Sengdang-ni area to an Army hospital. By the end of combat in 1953, 21,212 soldiers had been medevaced by helicopters.
Only the second military helicopter, the H-5 was frequently flown overloaded and outside of its center of gravity limits. The helicopter was not armed, though the pilot normally carried a .45-caliber automatic pistol and the crewman an M1 carbine.
Eleven civil Sikorsky S-51 helicopters had been purchased in 1947 and designated R-5F. This was later changed to H-5F. It was a four-place, single engine helicopter, operated by one pilot. The cabin was built of aluminum with Plexiglas windows. The fuselage was built of plastic-impregnated plywood, and the tail boom was wood monocoque construction. The main rotor consisted of three fully-articulated blades built of metal spars and plywood ribs and covered with two layers of fabric. (All metal blades soon became available.) The three bladed semi-articulated tail rotor was built of laminated wood. The main rotor turned counter-clockwise, as seen from above. (The advancing blade is on the helicopter’s right.) The tail rotor was mounted on the helicopter’s left side in a pusher configuration. It turned clockwise as seen from the helicopter’s left.
The helicopter’s fuselage was 41 feet, 7.5 inches (12.687 meters). The main rotor had a diameter of 48 feet (14.630 meters) and tail rotor diameter was 8 feet, 5 inches (2.2.565 meters) giving the helicopter an overall length of 57 feet, 1 inch (17.399 meters). It was 13 feet, 1.5 inches (4.001 meters) high. The landing gear tread was 12 feet (3.7 meters). The S-51 had an empty weight of 4,050 pounds (1,837.05 kilograms) and maximum takeoff weight of 5,500 pounds (2,494.76 kilograms). Fuel capacity was 100 gallons (378.5 liters).
The helicopter was powered by a 985-cubic-inch-displacement (16.14 liter) Pratt and Whitney R-985 AN-5 or -7 Wasp air-cooled, supercharged, 9-cylinder radial engine placed horizontally in the fuselage behind the crew compartment. The engine was rated at 450 horsepower, Standard Day at Sea Level.
The H-5F had a maximum speed (Vne) of 107 knots (123.1 miles per hour/198.2 kilometers per hour). Range was 275 miles (442.6 kilometers). The service ceiling was 14,800 feet (4,511 meters). The absolute hover ceiling was 3,000 feet (914.4 meters).
4 August 1908: Ferdinand Adolf Heinrich August Graf von Zeppelin, to demonstrate the capabilities of his airship, LZ 4, departed from its floating hangar on Lake Constance at 6:22 a.m., 4 August 1908, on a planned 24-hour round trip down the Rhine to Basel, Strasbourg and Mainz, then back to Stuttgart, a distance of approximately 435 miles.
LZ 4 was 176 meters (577 feet, 5 inches) long and 13 meters (42 feet, 8 inches) in diameter. Buoyancy was provided by hydrogen contained in 17 rubberized cotton gas bags inside the dirigible’s rigid structure The total volume of the airship was 15,200 cubic meters (536,782.9 cubic feet). It was propelled by two Daimler engines, producing 110 horsepower each, and driving three-bladed propellers. Its maximum speed was 47 kilometers per hour (29.2 miles per hour).
3 August 1972: During a 45-minute test flight at Edwards Air Force Base, the McDonnell Douglas YF-15A-1-MC Eagle prototype, 71-0280, went supersonic for the first time, reaching Mach 1.5.
An air-superiority fighter, the F-15 entered service with the United States Air Force in 1975. More than 1,500 fighter, two-seat trainer, and two-seat F-15E Strike Eagle fighter-bombers have been built by McDonnell Douglas and Mitsubishi. It is operated by allied air forces around the world and is expected to remain in front line service until 2025.
3 August 1962: Following his record-setting flight into space aboard an X-15 hypersonic research rocketplane, 17 July 1962, Major Robert M. White, U.S. Air Force, was featured with a cover photograph on the LIFE Magazine issue for the week of 3 August 1962. LIFE was the most prestigious news magazine of its time.
This was the first time that a manned aircraft had gone higher than 300,000 feet (91,440 meters). It was also the first flight above 50 miles (80.47 kilometers). For that achievement, Bob White became the first X-15 pilot to be awarded U.S. Air Force astronaut wings. His 314,750-foot altitude (95,936 meters) also established a Fédération Aéronautique Internationale (FAI) world altitude record, which will probably never be broken. To qualify, a new record would have to exceed White’s altitude by at least 3%, or more than 324,419 feet (98,882.9 meters). As the FAI-recognized boundary of Space is the Kármán line (100 kilometers, or 328,083.99 feet), any prospective challenger would have to hit a very narrow band of the atmosphere.
Major White had been the first pilot to fly faster than Mach 4, Mach 5 and Mach 6. He was the first to fly over 200,000 feet (60,960 meters), then over 300,000 feet (91,440 meters). He was a graduate of the Air Force Experimental Test Pilot School and flew tests of many aircraft at Edwards before entering the X-15 program. He made at total of sixteen X-15 flights.
A P-51 Mustang fighter pilot in World War II, Bob White was shot down on his 52nd combat mission in February 1945 and captured. He was held as a prisoner of war until the war in Europe came to an end in April 1945. White was recalled to active duty during the Korean War and was assigned to a fighter squadron stationed in Japan. Later, he flew 70 combat missions over North Vietnam in the Republic F-105 Thunderchief supersonic fighter bomber, including leading the attack against the Paul Doumer Bridge at Hanoi, 11 August 1967, for which he was awarded the Air Force Cross.
Colonel White next went to Wright-Patterson Air Force Base, Ohio, where he was director of the McDonnell Douglas F-15 Eagle systems program. He then returned to Edwards Air Force Base, California, as commander of the Air Force Flight Test Center. White was promoted to Major General in 1975.
General White retired from the U.S. Air Force in 1981. He died 17 March 2010.