10 June 1969: The U.S. Air Force donated the first North American Aviation X-15, serial number 56-6670, to the Smithsonian Institution for display at the National Air and Space Museum.
The first of three X-15A hypersonic research rocketplanes built by North American for the Air Force and the National Advisory Committee (NACA, the predecessor of NASA), 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.
Scott Crossfield, North American’s Chief Engineering Test Pilot, made the first unpowered flight 8 June 1959 and the first powered flight, 17 September 1959. NASA Research Test Pilot William H. “Bill” Dana made the final X-15 flight on 24 October 1968.
1 October 1942: At Muroc Dry Lake, in the high desert north of Los Angeles, California, Bell Aircraft Corporation’s Chief Test Pilot, Robert Morris Stanley, made the first flight of the top secret prototype turbojet-powered fighter, the Bell XP-59A Airacomet, serial number 42-108784. Weather was “C.A.V.U.” (Ceiling and Visibility Unrestricted) and wind was from the west at 20 miles per hour (9 meters per second).
In his report, Stanley wrote:
“4. All take-offs were made using 15,000 r.p.m. on both engines with flaps fully up and with the airplane pulled off the ground at about 80 to 90 m.p.h. Throttle was applied promptly and acceleration during take-off appeared quite satisfactory. The run was estimated to be in the vicinity of 2,000 feet, possibly more. The first flight reached an altitude of approximately 25 feet, and landing was made using partial power without flaps. This take-off had the wind approximately 60° on the right bow and must be considered a cross-wind take-off.
“5. Aileron and elevator action appear satisfactory, although the rudder force appears undesirably light causing the airplane to yaw somewhat for very light pedal pressures. Left rudder was needed for take-off due to cross wind.”
—Bell Aircraft Corp. Pilot’s Report 27-923-001, at Page 1-12, by Robert M. Stanley, 1 October 1942
Stanley made three more flights that day, as high as 100 feet (30.5 meters). The following day, Army Air Corps test pilot Colonel Laurence C. Craigie conducted the “official” first flight, reaching an altitude of 10,000 feet (3,048 meters).
Three XP-59A prototypes were built. The number one ship, 42-108784, was affectionately nicknamed Miss Fire, because of the initial difficulty in getting the engines to start.
The Bell XP-59A was conventional single-place airplane with retractable tricycle landing gear. It was primarily of metal construction, though the control surfaces were fabric-covered. The prototype was 38 feet, 10 inches (11.836 meters) long with a wingspan of 49 feet, 0 inches (14.935 meters) and overall height of 12 feet, 3¾ inches (3.753 meters), at rest. The leading edge of the wings were swept aft 7°. The angle of incidence was +2° with -2° twist and 2½° dihedral. The horizontal stabilizer had a span of 16 feet, 8 inches (5.080 meters). Its angle of incidence was +1½° with no dihedral. The vertical fin had 0° offset. The empty weight of the XP-59A was 7,319 pounds (3,320 kilograms) and its maximum gross weight was 10,089 pounds (4,576 kilograms).
The experimental fighter was initially powered by two General Electric Type I-A centrifugal reverse-flow turbojet engines, serial numbers 170121 (left) and 170131 (right), each producing 1,250 pounds of thrust (5.561 kilonewtons) at 15,000 r.p.m. These were copies of the British Whittle W.2B engines. They were heavy, underpowered and unreliable.
Performance of the XP-59A was disappointing with a maximum speed of 350 miles per hour (563 kilometers per hour) at Sea Level and 389 miles per hour (626 kilometers per hour) at 35,160 feet (10,717 meters), significantly slower than many piston-engined fighters.
Three XP-59A prototypes and thirteen YP-59A preproduction airplanes were built. The P-59 was ordered into production and Bell Aircraft Corporation built thirty P-59A and twenty P-59B fighters. These were armed with one M4 37mm autocannon with 44 rounds of ammunition and three Browning AN-M2 .50-caliber machine guns with 200 rounds per gun.
Although a YP-59A had set an unofficial altitude record of 47,600 feet (14,508 meters), the Airacomet was so outclassed by standard production fighters that no more were ordered.
The race for a jet engine-powered fighter had been ongoing for several years, and the United States’ XP-59A was trailing behind. The first jet airplane, the Heinkel He 178, had made its first flight in Germany three years earlier, on 27 August 1939, though it was a proof-of-concept article, not an operational military aircraft. In the United Kingdom, the Gloster E/28.39, also a proof-of-concept aircraft, though more advanced than the Heinkel, made its first flight, 15 May 1941. The world’s first operational jet fighter, the Messerschmitt Me 262, made its first flight on 18 July 1942. It was nearly two years before production Me 262s entered combat, but they were devastating against bomber formations. The Gloster Meteor, the Allies’ first jet fighter, first flew 5 March 1943, and deliveries to fighter squadrons began in July 1944. The de Havilland DH.100 Vampire made its first flight 20 September 1943, but it did not become operational until after the end of World War II.
The XP-59A flew nearly five months before its British cousin, but would not be assigned to an operational squadron, the 445th Fighter Squadron, 412th Fighter Group, until June 1945.
The first American military jet aircraft, Bell XP-59A Airacomet 42-108784, was preserved by the Army at Muroc, and the engines at Wright Field, Ohio. In 1978, these were given to the Smithsonian Institution National Air and Space Museum where the prototype was later restored and placed on display.g9
12 July 1957: President Dwight D. Eisenhower was the first United States president to fly in a helicopter when a U.S. Air Force H-13J-BF Sioux, serial number 57-2729 (c/n 1576), flown by Major Joseph E. Barrett, USAF, departed the White House lawn for Camp David, the presidential retreat in the Catoctin Mountains of Maryland. Also on board was a U.S. Secret Service special agent. A second H-13J, 57-2728 (c/n 1575), followed, carrying President Eisenhower’s personal physician and a second Secret Service agent.
The helicopter was intended to rapidly move the president from the White House to Andrews Air Force Base where his Lockheed VC-121E Constellation, Columbine III, would be standing by, or to other secure facilities in case of an emergency.
Major Barrett had been selected because of his extensive experience as a combat pilot. During World War II, he had flown the B-17 Flying Fortress four-engine heavy bomber. During the Korean War, Barrett had carried out a helicopter rescue 70 miles (113 kilometers) behind enemy lines, for which he was awarded the Silver Star.
The two helicopters were manufactured by the Bell Helicopter Company at Fort Worth, Texas, and delivered to the Air Force at Wright-Patterson Air Force Base on 29 March 1957. The presidential H-13Js were nearly identical to the commercial Bell Model 47J Ranger. The H-13J differed from the civil Model 47J by the substitution of main rotor blades of all-metal construction in place of the standard laminated wood blades.
Capable of carrying a pilot and up to three passengers, the Ranger was constructed with an enclosed cabin built on a tubular steel framework with all-metal semi-monocoque tail boom. The main rotor diameter was 37 feet, 2.00 inches (11.328 meters) and tail rotor diameter was 5 feet, 10.13 inches (1.781 meters), which gave the helicopter an overall length of 43 feet, 3¾ inches (13.185 meters) with rotors turning. The height (to the top of the centrifugal flapping restraints) was 9 feet, 8 inches (2.946 meters). The helicopter had a maximum gross weight of 2,800 pounds (1,270 kilograms).
The main rotor, in common to all American-designed helicopters, rotates counter-clockwise as seen from above. (The advancing blade is on the helicopter’s right.) The anti-torque (tail) rotor is mounted to the right side of an angled tail boom extension, in a tractor configuration, and rotates counter-clockwise as seen from the helicopter’s left. (The advancing blade is above the axis of rotation.)
The main rotor is a two-bladed, under-slung, semi-rigid assembly that would be a characteristic of helicopters built by Bell for decades. The main rotor system incorporates a stabilizer bar, positioned below and at right angles to the main rotor blades. Teardrop-shaped weights are placed at each end of the bar, on 100-inch (2.540 meters) centers. The outside diameter of the stabilizer bar is 8 feet, 6.781 inches (2.611 meters). (A similar system is used on the larger Bell 204/205/212 helicopters.)
The H-13J was powered by an air-cooled, normally-aspirated 433.972-cubic-inch-displacement (7.112 liter) AVCO Lycoming VO-435-A1B (O-435-21) vertically-opposed 6-cylinder direct-drive engine. The VO-435 had a compression ration of 7.3:1. It was rated at 220 horsepower at 3,200 r.p.m., maximum continuous power, and 260 horsepower at 3,200 r.p.m. for takeoff. The VO-435-A1B weighed 393.00 pounds (178.262 kilograms).
Engine torque is sent through a centrifugal clutch to a 9:1 gear-reduction transmission, which drives the main rotor through a two-stage planetary gear system. The transmission also drives the tail rotor drive shaft, and through a vee-belt/pulley system, a large fan to provide cooling air for the engine.
Fuel was carried in two gravity-feed tanks, mounted above and on each side of the engine. The total fuel capacity was 34.0 gallons (128.7 liters)
Cruise speed for the H-13J was 87–98 miles per hour (140–158 kilometers per hour), depending on gross weight, and its maximum speed was 105 miles per hour (169 kilometers per hour). The helicopter had a hover ceiling in ground effect (HIGE) of 8,100 feet (2,469 meters). The service ceiling was 15,000 feet (4,572 meters).
Both H-13J Sioux served as presidential aircraft until 1962. They were redesignated UH-13J and continued in use for VIP transportation until 1967.
Bell UH-13J-BF Sioux 57-2729 is in the collection of the Smithsonian Institution National Museum National Air and Space Museum, Steven V. Udvar-Hazy Center, while its sister ship, 57-2728, is at the National Museum of the United States Air Force, Wright-Patterson Air Force Base, Ohio, along with Columbine III.