16 February 1946: The Sikorsky S-51 prototype, NX92800, made its first flight. The test pilot was Dimitry D. (“Jimmy”) Viner, who later made the first civilian rescue using a helicopter. The S-51 was the first helicopter intended for commercial use, though it was also widely used by military services worldwide. (The prototype was later delivered to Aéronavale, French Naval Aviation.)
The S-51 was a commercial version of the Sikorsky R-5 series military helicopters. 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 986.749-cubic-inch-displacement (16.170 liter) air-cooled, supercharged, Pratt & Whitney Wasp Jr. T1B4 (R-985 AN-5) direct-drive, nine-cylinder radial engine which was placed vertically in the fuselage behind the crew compartment. This engine had a compression ratio of 6:1 and was rated at 450 horsepower at 2,300 r.p.m., Standard Day at Sea Level. The R-985 AN-5 was 48.00 inches (1.219 meters) long, 46.25 inches (1.175 meters) in diameter and weighed 684 pounds (310.3 kilograms) with a magnesium crankcase.
The S-51 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).
Of 220 helicopters in the S-51 series built by Sikorsky, 55 were commercial models.
13 February 1923: Brigadier General Charles Elwood Yeager, United States Air Force (Retired), was born at Myra, West Virginia.
“Who is the greatest pilot I ever saw? Well, uh. . . Well, let me tell you. . . .”
The following is from the official U.S. Air Force biography: (Photographs from various sources)
“The world’s first man-made sonic boom told the story. On Oct. 14, 1947, over dry Rogers Lake in California, Chuck Yeager rode the X-1, attached to the belly of a B-29 bomber, to an altitude of 25,000 feet. After releasing from the B-29, he rocketed to an altitude of 40,000 feet. Moments later he became the first person to break the sound barrier, safely taking the X-1 he called Glamorous Glennis to a speed of 662 mph, faster than the speed of sound at that altitude. His first words after the flight were, ‘I’m still wearing my ears and nothing else fell off neither.’
“Yeager was born in February 1923 in Myra, W. V. In September 1941, he enlisted as a private in the Army Air Corps. He was soon accepted for pilot training under the flying sergeant program and received his pilot wings and appointment as a flight officer in March 1943 at Luke Field, Ariz.
“His first assignment was as a P-39 pilot with the 363rd Fighter Squadron, Tonopah, Nev. He went to England in November 1943 and flew P-51s in combat against the Germans, shooting down one ME-109 and an HE-111K before being shot down on his eighth combat mission over German-occupied France on March 5, 1944. He evaded capture by the enemy when elements of the French Maquis helped him to reach the safety of the Spanish border. That summer, he was released to the British at Gibraltar and returned to England. He returned to his squadron and flew 56 more combat missions, shooting down 11 more enemy aircraft.
“Returning to stateside, Yeager participated in various test projects, including the P-80 Shooting Star and P-84 Thunderjet. He also evaluated all the German and Japanese fighter aircraft brought back to the United States after the war. This assignment led to his selection as pilot of the nation’s first research rocket aircraft, the Bell X-1, at Muroc Army Air Field (now Edwards Air Force Base, Calif.). After breaking the sound barrier in 1947, Yeager flew the X-1 more than 40 times in the next two years, exceeding 1,000 mph and 70,000 feet. He was the first American to make a ground takeoff in a rocket-powered aircraft. In December 1953 he flew the Bell X-1A 1,650 mph, becoming the first man to fly two and one-half times the speed of sound.
“After a succession of command jobs, Yeager became commandant of the Aerospace Research Pilot School (now the U.S. Air Force Test Pilot School), where all military astronauts were trained.
“On Dec. 10, 1963, he narrowly escaped death while testing an NF-104 rocket-augmented aerospace trainer. His aircraft went out of control at 108,700 feet (nearly 21 miles up) and crashed. He parachuted to safety at 8,500 feet after battling to gain control of the powerless aircraft. He thus became the first pilot to make an emergency ejection in the full pressure suit needed for high altitude flights. Yeager has flown more than 200 types of military aircraft and has more than 14,000 hours, with more than 13,000 of them in fighter aircraft.
“Yeager retired from active duty in the U. S. Air Force in March 1975, after serving as the United States defense representative to Pakistan and director of the Air Force Inspection and Safety Center, Norton AFB, Calif.
“Retirement was never part of his plans. He remains an active aviation enthusiast, acting as adviser for various films, programs and documentaries on aviation. He has published two books, entitled Yeager, An Autobiography and Press On: Further Adventures in the Good Life.”
11 February 1939: Barely two weeks after its first flight, First Lieutenant Benjamin Scovill (“Ben”) Kelsey, U.S. Army Air Corps, took the prototype Lockheed XP-38, 37-457, on a record-breaking transcontinental flight from March Field, Riverside, California, to Mitchel Field, Long Island, New York.
Lieutenant Kelsey departed March Field at 6:32 a.m., Pacific Standard Time, (9:32 a.m., Eastern) and flew to Amarillo, Texas for the first of two refueling stops. He arrived there at 12:22 p.m., EST, and remained on the ground for 22 minutes. The XP-38 took off at 12:44 p.m., EST, and Kelsey flew on to Wright Field, Dayton, Ohio. He landed there at 3:10 p.m. EST.
Kelsey was met by Major General H.H. Arnold, and it was decided to continue to New York. The XP-38 was airborne again at 3:28 p.m., EST, on the final leg of his transcontinental flight.
Kelsey was overhead Mitchel Field, New York at 4:55 p.m., Eastern Standard Time, but his landing was delayed by other airplanes in the traffic pattern.
On approach, the XP-38 was behind several slower training planes, so Lieutenant Kelsey throttled back the engines. When he tried to throttle up, the carburetor venturis iced and the engines would not accelerate, remaining at idle. The airplane crashed on a golf course short of the airport.
The total elapsed time was 7 hours, 45 minutes, 36 seconds but Kelsey’s actual flight time was 7 hours, 36 seconds. The prototype had averaged 340 miles per hour (547 kilometers per hour) and had reached 420 miles per hour (676 kilometers per hour) during the Wright Field-to-Mitchel Field segment.
Kelsey’s transcontinental flight failed to break the transcontinental speed record set two years earlier by Howard R. Hughes by 17 minutes, 11 seconds. It should be noted, however, that Hughes H-1 Racer flew non-stop from coast to coast, while the XP-38 required two time-consuming fuel stops.
The XP-38 was damaged beyond repair, but its performance on the transcontinental flight was so impressive that 13 YP-38s were ordered from Lockheed by the Air Corps.
Designed by an engineering team led by Hall L. Hibbard, which included the legendary Clarence L. “Kelly” Johnson, the XP-38 was a single-place, twin-engine fighter designed for very high speed and long range. It was an unusual configuration with the cockpit and armament in a center nacelle, with two longitudinal booms containing the engines and propellers, turbochargers, radiators and coolers. The Lightning was equipped with tricycle landing gear. The nose strut retracted into the center nacelle and the two main gear struts retracted into bays in the booms. To reduce drag, the sheet metal used butt joints with flush rivets.
The XP-38 was 37 feet, 10 inches (11.532 meters) long with a wingspan of 52 feet (15.850 meters) and overall height of 12 feet, 10 inches (3.952 meters). Its empty weight was 11,507 pounds (5,219.5 kilograms). The gross weight was 13,904 pounds (6,306.75 kilograms) and maximum takeoff weight was 15,416 pounds (6,992.6 kilograms).
The Lightning was the first production airplane to use the Harold Caminez-designed, liquid-cooled, supercharged, 1,710.60-cubic-inch-displacement (28.032 liter) Allison Engineering Company V-1710 single overhead cam 60° V-12 engines. When installed on the P-38, these engines rotated in opposite directions. The XP-38 used a pair of experimental C-series Allisons, with the port V-1710-C8 (V-1710-11) engine being a normal right-hand tractor configuration, while the starboard engine, the V-1710-C9 (V-1710-15), was a left-hand tractor. Through a 2:1 gear reduction, these engines drove the two 11-foot (3.353 meters) diameter, three-bladed Curtiss Electric variable-pitch propellers inward to counteract the torque effect of the engines and propellers. (Viewed from the front of the airplane, the XP-38’s starboard propeller turned clockwise, the port propeller turned counter-clockwise. The direction of rotation was reversed in the YP-38 service test prototypes and production P-38 models.) The engines have long propeller gear drive sections to aid in streamlining aircraft, and are sometimes referred to as “long-nose Allisons.”
The V-1710-11 and -15 had a compression ratio of 6.65:1. They had a continuous power rating of 1,000 horsepower at 2,600 r.p.m. at Sea Level, and 1,150 horsepower at 2,950 r.p.m. for takeoff. The combination of a gear-driven supercharger and an exhaust-driven General Electric B-1 turbosupercharger allowed these engines to maintain their rated power levels to an altitude of 25,000 feet (7,620 meters).
The -11 and -15 were 7 feet, 10.46 inches (2.399 meters) long. The -11 was 3 feet, 6.59 inches (1.082 meters) high and 2 feet, 4.93 inches (0.7348 meters) wide. It weighed 1,300 pounds (589.7 kilograms). The -15 was 3 feet, 4.71 inches (1.034 meters) high, 2 feet, 4.94 inches (0.7351 meters) wide, and weighed 1,305 pounds (591.9 kilograms).
The XP-38 had a maximum speed of 413 miles per hour (664.66 kilometers per hour) at 20,000 feet (6,096 meters) and a service ceiling of 38,000 feet (11,582.4 meters).
The XP-38 was unarmed, but almost all production Lightnings carried a 20 mm auto cannon and four Browning .50-caliber machine guns grouped together in the nose. They could also carry bombs or rockets and jettisonable external fuel tanks.
Testing continued with thirteen YP-38A pre-production aircraft and was quickly placed in full production. The P-38 Lightning was one of the most successful combat aircraft of World War II. By the end of the war, Lockheed had built 10,037 Lightnings.
9 February 1969: At 11:34 a.m., Boeing Chief Test Pilot Jack Wadell, with Engineering Test Pilots Brien Singleton Wygle, co-pilot, and Jesse Arthur Wallick, flight engineer, took off from Paine Field, Everett, Washington, aboard RA001, the prototype Boeing 747-121, FAA registration N7470, and made a 1 hour, 15 minute test flight. The ship was named City of Everett after the home of the factory where it was built.
The 747 was the first “wide body” airliner and was called a “jumbo jet”. It is one of the most widely used airliners and air freighters in service world-wide, and is still in production after 45 years. The latest version is the 747-8, the “Dash Eight.” As of December 2012, Boeing had built 1,458 747s.
The 747-100 series was the first version of the Boeing 747 to be built. It was operated by a flight crew of three and was designed to carry 366 to 452 passengers. It is 231 feet, 10.2 inches (70.668 meters) long with a wingspan of 195 feet, 8 inches (59.639 meters) and overall height of 63 feet, 5 inches (19.329 meters). The interior cabin width is 20 feet (6.096 meters), giving it the name “wide body.” Its empty weight is 370,816 pounds (168,199 kilograms) and the Maximum Takeoff Weight (MTOW) is 735,000 pounds (333,390 kilograms).
The 747-100 is powered by four Pratt & Whitney JT9D-7A high-bypass ratio turbofan engines. The JT9D is a two-spool, axial-flow turbofan engine with a single-stage fan section, 14-stage compressor (11 high- and 3 low-pressure stages) and 6-stage turbine (2 high- and 4 low-pressure stages). The engine is rated at 46,950 pounds of thrust (208.844 kilonewtons), or 48,570 pounds (216.050 kilonewtons) with water injection (2½-minute limit). This engine has a maximum diameter of 7 feet, 11.6 inches (2.428 meters), is 12 feet, 10.2 inches (3.917 meters) long and weighs 8,850 pounds (4,014 kilograms).
The 747-100 has a cruise speed of 0.84 Mach (555 miles per hour, 893 kilometers per hour) at 35,000 feet (10,668 meters). The maximum certificated operating speed is 0.92 Mach. The airliner’s maximum range is 6,100 miles (9,817 kilometers).
The Boeing 747 has been in production for 48 years. More than 1,520 have been delivered to date. 205 of these were the 747-100 series. The U.S. Air Force has selected the Boeing 747-8 as the next presidential transport aircraft.
City of Everett last flew in 1995. It is on static display at The Museum of Flight, Boeing Field, Seattle, Washington. A cosmetic restoration is underway. Online donations to help cover the expenses are being accepted. See:
4 February 1969: The North American Aviation XB-70A-1-NA Valkyrie, 62-0001, made its very last flight from Edwards Air Force Base, California, to Wright-Patterson Air Force Base, Ohio. NASA Research Test Pilot Fitzhugh L. Fulton, Jr., Lieutenant Colonel, U.S. Air Force (Retired), and Lieutenant Colonel Emil Sturmthal, U.S. Air Force, were the flight crew for this final flight.
On arrival at Wright-Patterson, Fulton closed out the log book and handed it over to the curator of the National Museum of the United States Air Force.
The Mach 3+ prototype strategic bomber and high-speed, high-altitude research airplane had completed 83 flights for a total of 160 hours, 16 minutes of flight time.
62-0001 was the first of three prototype Mach 3+ strategic bombers. (The third prototype, XB-70B 62-0208, was not completed.) The Valkyrie utilized the most advanced technology available. Materials and manufacturing techniques had to be developed specifically to build this airplane. It is a large delta wing airplane with a forward canard and two vertical fins. The outer 20 feet (6.096 meters) of each wing could be lowered to a 25° or 65° angle for high speed flight. Although this did provide additional directional stability, it actually helped increase the compression lift, which supported up to 35% of the airplane’s weight in flight.
The XB-70A is 185 feet, 10 inches (56.642 meters) long with a wingspan of 105 feet (32.004 meters) and overall height of 30 feet, 9 inches (9.373 meters). Fully loaded, the Valkyrie weighs 534,700 pounds (242,535 kilograms).
It is powered by six General Electric YJ93-GE-3 turbojet engines which were rated at 22,000 pounds of thrust (97.86 kilonewtons) at Sea Level, and 31,000 pounds (137.89 kilonewtons) with afterburner. The J93 was a single-shaft axial-flow turbojet with an 11-stage compressor section and two-stage turbine. It was 235.0 inches (5.969 meters) long, 55.0 inches (1.397 meters) in diameter, and weighed 4,770 pounds (2,164 kilograms).
The maximum speed achieved was Mach 3.1 (2,056 miles per hour, or 3,308.8 kilometers per hour) at 73,000 feet (22,250 meters). The service ceiling is 73,350 feet (23,357 meters).
The second Valkyrie, XB-70A-2-NA 62-0207, was destroyed when it crashed after a mid-air collision with a Lockheed F-104N Starfighter flown by NASA Chief Research Test Pilot Joseph A. Walker, 8 June 1966. Both Walker and the B-70’s co-pilot, Major Carl S. Cross, U.S. Air Force, were killed.
XB-70A Valkyrie 62-0001 is in the collection of the National Museum of the United States Air Force.