1 August 1955: Test pilot Anthony W. LeVier made the first flight flight of the Lockheed U-2 high-altitude reconnaissance airplane at Groom Lake, Nevada. LeVier was conducting taxi tests in preparation for the planned first flight a few days away, when at 70 knots the U-2 unexpectedly became airborne.
LeVier later said, “I had no intentions whatsoever of flying. I immediately started back toward the ground, but had difficutly determining my height because the lakebed had no markings to judge distance or height. I made contact with the ground in a left bank of approximately 10 degrees.”
On touching down on the dry lake, the U-2’s tires blew out and the brakes caught fire. A landing gear oleostrut was leaking. Damage was minor and the airplane was soon ready to fly. Tony LeVier was again in the cockpit for the first actual test flight on 4 August.
The Lockheed U-2A is a single-place, single-engine aircraft powered by a turbojet engine, intended for very high altitude photographic reconnaissance. Thirty U-2A aircraft were designed and built for the Central Intelligence Agency by Lockheed Aircraft Corporation’s secret “Skunk Works” under the supervision of Clarence L. “Kelly” Johnson.
The company designation for the proposed aircraft was CL-282. Its fuselage was very similar to the XF-104 Starfighter and could be built using the same tooling. The reconnaissance airplane was produced under the code name Operation AQUATONE.
The U-2A was 46 feet, 6 inches (14.173 meters) long with a wingspan of 80 feet (24.384 meters). Its empty weight was 10,700 pounds (5,307 kilograms) and the gross weight was 16,000 pounds (7,257 kilograms). The engine was a Pratt and Whitney J57-P-37A which produced 10,200 pounds of thrust. This gave the U-2A a maximum speed of 528 miles per hour (850 kilometers per hour) and a ceiling of 85,000 feet (25,908 meters). It had a range of 2,200 miles (3,541 kilometers).
Because of the very high altitudes that the U-2 was flown, the pilot had to wear a David Clark Co. MC-3 partial-pressure suit with an International Latex Corporation MA-2 helmet and faceplate. The partial-pressure suit used a system of capstans and air bladders to apply pressure to the body as a substitute for a loss of atmospheric pressure. Each suit was custom-tailored for the individual pilot.
On 4 April 1957, Article 341 was flown by Lockheed test pilot Robert Sieker. At 72,000 feet (21,946 meters) the engine flamed out and the cockpit pressurization failed. Parts of the U-2 had been coated with a plastic material designed to absorb radar pulses to provide a “stealth” capability. However, this material acted as insulation, trapping heat from the engine inside the fuselage. This lead to a number of engine flameouts.
Sieker’s partial-pressure suit inflated, but the helmet’s faceplate did not properly seal. He lost conciousness and at 65,000 feet (19,812 meters) the U-2 stalled, then entered a flat spin. Sieker eventually regained consciousness at lower altitude and bailed out. He was struck by the airplane’s tail and was killed. The first U-2 crashed northwest of Pioche, Nevada, and caught fire. Robert Sieker’s body was found approximately 200 feet (61 meters) away.
Because of the slow rate of descent of the airplane while in a flat spin, the impact was not severe. Portions of Article 341 that were not damaged by fire were salvaged by Lockheed and used to produce another airframe.
For her around-the-world flight, the airplane that Amelia Earhart chose was a Lockheed Electra 10E, manufactured by the Lockheed Aircraft Company, Burbank, California. The Electra Model 10 was an all-metal, twin-engine, low-wing monoplane with retractable landing gear, designed as a small, medium-range airliner. In the standard configuration it carried a crew of 2 and up to 10 passengers. The Model 10 was produced in five variants with a total of 149 airplanes built between August 1934 and July 1941. Lockheed built fifteen Model 10Es. Earhart’s was serial number 1055.
$80,000 to buy the Electra was provided by the Purdue Research Foundation from donations made by several individuals. George Palmer Putnam, Amelia’s husband, made the arrangements to order the airplane and in March 1936 gave Lockheed the authorization to proceed, with delivery requested in June. The modifications included four auxiliary fuel tanks in the passenger compartment, a navigator’s station to the rear of that, elimination of passenger windows, installation of a Sperry autopilot and various radio and navigation equipment and additional batteries. The Electra was not ready until mid-July.
Amelia Earhart test flew the new airplane at Burbank on 21 July with Lockheed test pilot Elmer C. McLeod. She accepted the Electra on her 39th birthday, 24 July 1936. It received civil certification NR16020. (The letter “R” indicates that because of modifications from the standard configuration, the airplane was restricted to carrying only members of the flight crew, although Earhart and her advisor, Paul Mantz, frequently violated this restriction.)
The Electra 10E was 38 feet, 7 inches (11.760 meters) long with a wingspan of 55 feet (16.764 meters) and overall height of 10 feet, 1 inch (3.074 meters). The standard Model 10 had an empty weight of 6,454 pounds (2,927.5 kilograms) and a gross weight of 10,500 pounds (4,762.7 kilograms). NR16020 had an empty weight of 7,265 pounds (3295.4 kilograms). Lockheed’s performance data was calculated using 16,500 pounds (7,484.3 kilograms) as the Maximum Takeoff Weight.
NR16020 had a total fuel capacity of 1,151 gallons (4,357 liters) in ten tanks in the wings and fuselage. 80 gallons (302.8 liters) of lubricating oil for the engines was carried in four tanks.
Earhart’s Electra 10E Special was powered by two air-cooled, supercharged, 1,343.804-cubic-inch-displacement (22.021 liter) Pratt & Whitney Wasp S3H1 nine-cylinder radial engines, with a compression ratio of 6:1. These engines used a single-stage centrifugal supercharger and were rated at 550 horsepower at 2,200 r.p.m. at 5,000 feet (1,524 meters) and 600 horsepower at 2,250 r.p.m. for take off. The direct-drive engines turned 9 foot, 7/8-inch (3.010 meters) diameter, two-bladed, Hamilton Standard variable-pitch, constant-speed propellers. The Wasp S3H1 is 4 feet, 3.60 inches (1.311 meters) in diameter and 3 feet, 7.01 inches (1.093 meters) long. It weighed 865 pounds (392 kilograms).
A detailed engineering report was prepared by a young Lockheed engineer named Clarence L. (“Kelly”) Johnson to provide data for the best takeoff, climb and cruise performance with the very heavily loaded airplane. The maximum speed for the Model 10E Special at Sea Level and maximum takeoff weight was 177 miles per hour (284.9 kilometers per hour), a reduction of 25 miles per hour (40.2 kilometers per hour) over the standard airplane. The maximum range was calculated to be 4,500 miles (7,242.1 kilometers) using 1,200 gallons (4,542.5 liters) of fuel.
Johnson would later design many of Lockheed’s most famous aircraft, such as the SR-71A Blackbird Mach 3+ strategic reconnaissance airplane. As a student at the University of Michigan, he worked on the wind tunnel testing of the Lockheed Electra Model 10 and made recommendations that were incorporated into the production airplane.
The Electra was heavily damaged when it crashed on takeoff at Luke Field (NAS Ford Island), Honolulu, Hawaii, on the morning of 20 March 1937. It was shipped back to Lockheed for extensive repairs. An investigating board of U.S. Army officers did not report a specific cause for the accident, but there was no evidence of a “blown tire” as had been reported in the newspapers. The repairs were completed by Lockheed and the aircraft certified as airworthy by a Bureau of Commerce inspector, 19 May 1937. The airplane had flown 181 hours, 17 minutes since it was built.
Earhart’s Electra was equipped with a Western Electric Model 13C radio transmitter and Model 20B receiver for radio communication. It used a Sperry GyroPilot gyroscopic automatic pilot.
26 April 1962: At a non-existent location in the Mojave Desert of Nevada, Lockheed Chief Test Pilot Louis Wellington (“Lou”) Schalk, Jr., was scheduled to take the first Oxcart for a high-speed taxi test on the specially constructed 8,000-foot (2.44 kilometer) runway. However, he had received secret, specific instructions from designer Kelly Johnson to take the craft, known as “Article 121,” airborne.
Lou Schalk roared down the runway and lifted off. He flew at about 20 feet for two miles. The super-secret aircraft was oscillating badly so he set it down straight ahead on the dry lake bed and disappeared into a cloud of dust and flying sand. Johnson said that it “was horrible to watch.” A few minutes later, the needle nose of Article 121 appeared out of the dust as Schalk taxied back to the runway. It turned out that some equipment had been hooked up backwards. Subsequent flights were made without difficulty.
This was the actual first flight of the Central Intelligence Agency’s Top Secret A-12 reconnaissance aircraft. The “official” first flight would come several days later.
Designed as the successor to the Agency’s subsonic U-2 spy plane, the twin-engine jet was capable of flying more than Mach 3 (over 2,000 miles per hour/3,218.7 kilometers per hour) and higher than 80,000 feet (24,384 meters). Built by Lockheed’s “Skunk Works,” the new airplane wasn’t “state of the art,” it was well beyond the state of the art. New materials were developed. New equipment designed and built. New manufacturing processes were invented.
The A-12, developed under the code name “Oxcart,” was unlike anything anyone had ever seen. The first A-12 was referred to as Article 121. “A” = “Article.” “12-” is for A-12. “-1” is for the first production aircraft. So you get “Article 121.” What could be simpler?
The A-12 was so fast and could fly so high that it was invulnerable to any defense. No missile or aircraft or gun could reach it.
Thirteen A-12s were built for the CIA. Two M-21 variants, built to carry the Mach 4 D-21 drone, were also produced. An interceptor version was developed for the Air Force as the YF-12A.
Ninety-three Lockheed F-12B interceptors were ordered though Secretary of Defense Robert S. McNamara refused to release the funding for production. After three years, the order was cancelled. The Air Force liked the A-12, however, and ordered 32 of the more widely known two-place SR-71A “Blackbird” reconnaissance ships.
Today, Article 121 is on display at the Blackbird Airpark, an annex of the Air Force Flight Test Museum, Edwards Air Force Base, California.
29 February 1964: President Lyndon B. Johnson publicly revealed the existence of the Top Secret Lockheed YF-12A, a Mach 3+ interceptor designed and built by Clarence L. “Kelly” Johnson’s “Skunk Works.” President Johnson referred to the interceptor as the “A-11.”
Intended as a replacement for Convair’s F-106 Delta Dart, three pre-production YF-12As were built for testing. On 1 May 1965, a YF-12A set a speed record of 2,070.103 miles per hour (3,331.507 kilometers per hour) and reached an altitude of 80,259 ft (24,463 meters).
The reason for President Johnson’s announcement of the existence of the YF-12A prototypes was to conceal the existence of the Central Intelligence Agency’s fleet of Lockheed A-12 Oxcart reconnaissance aircraft based at Groom Lake, Nevada. Any sightings of these aircraft could be attributed to test flights of the YF-12As based at Edwards Air Force Base, 160 miles (258 kilometers) to the southwest.
The YF-12A interceptor is very similar to its A-12 Oxcart and SR-71A Blackbird stablemates. It a large twin-engine delta wing aircraft, flown by a pilot and weapons system operator. Because of the altitudes that the F-12 operates, the crew wears S901F full-pressure suits produced by the David Clark Company. The A-12 is 101.6 feet (30.97 meters) long with a wingspan of 55.62 feet (16.953 meters) and overall height of 18.45 feet (5.624 meters). It has a zero fuel weight of 54,600 pounds (24,766 kilograms) and a maximum ramp weight of 124,600 pounds (56,518 kilograms). ¹
The YF-12A is powered by two Pratt & Whitney J58 (JT11D-20A) engines. These are single rotor bleed-bypass turbojets with a 9-stage compressor section and 2-stage turbine. They have a static thrust rating of 31,500 pounds (140.118 kilonewtons), each, at Sea Level with afterburning. The J58s use a unique JP-7 fuel.
The YF-12A has a maximum speed of Mach 3.35 (2,232 miles per hour/3,342 kilometers per hour) at 80,000 feet (24,384 meters). The A-12 has a normal operating cruise speed of Mach 3.1. Its maximum operating altitude is 85,000 feet (25,908 meters) and it has a range of 3,000 miles (4,828 kilometers). Unlike most fighters, the A-12 has a maximum load factor of 2.5 gs. Its maximum bank angle when above Mach 2.5 is 30°.
The United States Air Force ordered 93 production F-12B aircraft, which would have been armed with three Hughes AIM-47A Falcon air-to-air missiles in enclosed bays in the bottom of the fuselage. However, Secretary of Defense Robert S. McNamara refused to release the funds for the purchase for three consecutive years and eventually the project was cancelled.
The first YF-12A, 60-6934, seen in the top photograph, was extensively damaged by a brake system fire on landing at Edwards AFB, 14 August 1966. It was salvaged and rebuilt as SR-71C 61-7981. The third YF-12A, shown in the photograph below, was lost due to an inflight fire 24 June 1971. The crew safely ejected.
The only existing YF-12A, 60-6935, is in the collection of the National Museum of the United States Air Force at Wright-Patterson Air Force Base, Ohio.
¹ The Lockheed SR-71A has a length of 107.4 feet (32.74 meters). Wingspan and height are the same. Its zero fuel weight varied from 56,500–60,000+ pounds (25,628–27,216+ kilograms) and the gross weight had a range of approximately 135,000–140,000+ pounds (61,235–63,503+ kilograms).
23 February 1934: Test pilot Marshall Headle, Chief Pilot in Charge of Flight Operations for Lockheed Aircraft Company, took the prototype Lockheed Model 10 Electra, serial number 1001, registered NX233Y, for its first flight at United Airport, Burbank, California (which soon became United Air Terminal, then Lockheed Air Terminal and is now the Hollywood-Burbank Airport, BUR).
The Lockheed Model 10 Electra was designed as a 10-passenger commercial transport and was a contemporary of the Boeing Model 247. This was Lockheed’s first all-metal airplane. The Electra had two engines, a low wing and retractable landing gear. An engineering team led by Hall L. Hibbard worked on the airplane.
A young engineer, Clarence L. (“Kelly”) Johnson, an assistant aerodynamicist at the University of Michigan, performed the wind tunnel tests on scale models of the proposed design and recommended changes to the configuration, such as the use of two vertical fins mounted at the outboard ends of the horizontal stabilizer. This became a design feature of Lockheed airplanes into the 1950s and included the Model 14 Super Electra/Hudson, Model 18 Lodestar/PV-1 Ventura, the P-38 Lightning fighter and the L-1649 Starliner, which was produced until 1958. Johnson would become the leader of Lockheed’s legendary “Skunk Works.”
The prototype Electra was was used for certification testing. During a full-load test at Mines Field (now, LAX, Los Angeles International Airport) the Electra’s landing gear malfunctioned. Babe Headle flew the airplane back to Burbank and made a one-wheel landing. The prototype was slightly damaged but quickly repaired.
After testing was competed the prototype Electra was delivered to Northwest Airways, Inc., at St. Paul, Minnesota, 31 December 1934. The experimental registration was changed to a standard registration, NC233Y, and it was assigned the Northwest fleet number 60.
Like the Boeing 247, the Electra was originally produced with a forward-slanting windshield to prevent instrument light reflection during night flights. This resulted in ground lighting reflections, though, and was changed to a standard, rearward slant with the fifth production airplane. NC233Y was modified by Northwestern’s maintenance staff.
Lockheed built 147 Model 10s in various configurations. The first production variant was the Model 10A. It was 38 feet, 7 inches (11.760 meters) long with a wingspan of 55 feet (16.764 meters), and height of 10 feet, 1 inch (3.073 meters). The wings had a total area of 458.3 square feet (42.6square meters). Their angle of incidence was 0°, and there were 5° 34′ dihedral.
The airplane had an empty weight of 5,455 pounds (2,474 kilograms) and a gross weight of 9,000 pounds (4,082 kilograms).
The Model 10A was powered by two air-cooled, supercharged, 986.749-cubic-inch-displacement (16.170 liters) Pratt & Whitney Wasp Jr. SB 9-cylinder radial engines with a compression ratio of 6:1. They were rated at 400 horsepower at 2,200 r.p.m at 5,000 feet (1,524 meters), and 450 horsepower at 2,300 r.p.m. for takeoff, using 87-octane gasoline. The SB engines were direct-drive and turned two-bladed Smith variable-pitch propellers. The Wasp Jr. SB was 3 feet, 6.59 inches (1.056 meters) long, 3 feet, 11.75 inches (1.162 meters) in diameter, and weighed 645 pounds (293 kilograms). The engines were covered by NACA cowlings.
The airplane had a cruise speed of 190 miles per hour (306 kilometers per hour) at 5,000 feet (1,524 meters) and maximum speed of 215 miles per hour (346 kilometers per hour) at 8,000 feet (2,438 meters). The service ceiling was 20,000 feet ( meters) and the range at cruise speed was 750 miles (1,207 kilometers).
Newsreel footage of the Lockheed Model 10 prototype’s first flight, by cinematographer Alfred Dillimtash Black for Fox Movietone News, is in the collection of the Moving Image Research Collections, University of South Carolina, University Libraries, and can be viewed at:
The Electra was “the Lisbon plane” in the classic 1942 motion picture, “Casablanca,” which starred Humphrey Bogart, Ingrid Bergman, Paul Henreid and Claude Rains.
Probably the best-known Lockheed Electra is the Model 10E Special, NR16020, which was built for Amelia Earhart for her around-the-world flight attempt in 1937. She took delivery of the airplane on her 39th birthday, 24 July 1936.
The prototype Lockheed Model 10 later carried U.S. registrations NC2332, NC17380, and Canadian registration CF-BRG. It was placed in service with the Royal Canadian Air Force with the serial number 7652. One of 15 Lockheed Electras in RCAF service during World War II, it was destroyed by fire at RCAF Station Mountain View, Prince Edward County, Ontario, Canada, 14 October 1941.
Marshall Headle was born 21 March 1893 at Winthrop, Massachussetts, United States of America, He was the third child of Edwin Charles Headle, a clergyman, and Clarendo Yeomans Headle. He attended Winthrop High School before going on to the Massachussetts Agricultural College at Bolton. He graduated in 1912 with a Bachelor of Science degree (B.Sc.) in Floriculture.
Headle enlisted in the United States Army in 1917, and attended aviation ground school at the Massachusetts Institute of Technology (M.I.T.). His flight training took place at Tours, France. He held the rank of First Lieutenant, Air Service of the American Expeditionary Force, United States Army. Lieutenant Headle served as a flight instructor at Tours and at the 2nd Aviation Instruction Center.
From 1919 to 1922, Headle was attached to the United States Embassy in Paris, France. He then returned to the United States.
Marshall Headle enlisted as a private in the United States Marine Corps, 25 October 1924. He served with the Marines in China as an airplane crew chief and aviator. He was promoted to gunnery sergeant (Gy.Sgt.). He returned to the United States in 1928, and resigned from the Marine Corps to become a civilian pilot.
In 1929, Headle married Dorothea Evelyn Breeder. They had two children, Marshall Ronald Headle, born in 1932, and Michele Ann Headle. (Mrs. Headle died in Honolulu, Hawaii, 25 May 2010, at the age of 99 years.)
Headle joined Lockheed in 1929, as chief pilot, flight operations. On 30 October 1929, Headle made the first flight of the all-metal Detroit-Lockheed DL-2 Sirius.
In 1930, Headle attempted to set a world altitude record with a 500 kilogram (1,102 pounds) payload, flying a Lockheed Vega. He used a pressurized tank of oxygen with a flexible tube.
In 1931, he took the Model 9 Orion, NX960Y, on its first flight.
In 1933, became the company’s chief test pilot, succeeding Wiley Post. He also traveled world-wide demonstrating Lockheed’s airplanes.
Headle also made the first flight of Gerard Vultee’s Vultee V-1A single-engine airliner, 19 February 1933.
On 29 July 1937, he made the first flight of the Lockheed Model 14 Super Electra. The Model 14 fuselage was stretched, resulting in the Model 18 Lodestar. Headle, with Louis Upshaw, took the prototype, NX17385, for its first flight, 21 September 1939. The Lodestar would be developed into the Lockheed Ventura bomber.
On 16 September 1940, Headle made the first flight of the Lockheed YP-38 service test prototype. Headle was featured in magazine and billboard advertisements for Camel cigarettes in 1941.
In 1941, he was injured in an altitude chamber accident and was no longer able to fly.
Marshall Headle died 14 May 1945 at the age of 52 years. He was buried at the Valhalla Memorial Cemetery, Burbank, California.