Lockheed test pilot Louis W. Schalk, Jr. (Lockheed Martin)
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.
Lockheed A-12 60-6924 lands at Groom Lake, NV, after its first flight, 30 April 1962. (Lockheed Martin)
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.
Lockheed A-12 Oxcarts and YF-12As at Groom Lake, Nevada. (Central Intelligence Agency)
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.
Lockheed YF-12A 60-6934, the first of three prototype Mach 3+ interceptors. (U.S. Air Force)
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.”
The following day, the Los Angeles Times ran two lengthy articles on its front page:
Johnson Discloses New Jet Secretly Developed by U.S.
Manned Aircraft Flies at 3 Times Speed of Sound; Military Potential Great
By ROBERT C. TOTH
Times National Science Correspondent
WASHINGTON—President Johnson disclosed Saturday the secret five-year development of an experimental jet aircraft whose performance “far exceeds that of any other aircraft in the world today.”
Several of the craft, designated A-11, have been “tested in sustained flight” at speeds greater than 2,000 m.p.h. and at heights over 70,000 ft., he said.
The craft has been made possible “by major advances in aircraft technology of great significance to both military and commercial application,” Mr. Johnson told a press conference.
Tests are under way at Edwards AFB, Cal., to determine the capability of the airplanes as long-range interceptors of enemy bombers. The plane was developed by Lockheed Aircraft Corp. of Burbank as a special project.
“Appropriate members of the Senate and the House have been kept fully informed on the program since its day of inception” in 1959, Mr. Johnson said.
Costs of the A-11 were not revealed, and the President said detailed performance information on the aircraft “will remain strictly classified.” Personnel working on the project have been told to keep quiet, he added.
Why the project has been wrapped in secrecy was not immediately clear. All that a White House spokesman would say, in answer to a question, was the A-11 represents “a new plateau in aircraft potential”—of such great potential that the military wanted to “explore it in secrecy.”
The A-11’s development also will aid in building a supersonic transport for commercial airlines, Mr. Johnson said. Like A-11, the transport would fly about Mach 3, or three times the speed of sound.
One of the most important technological achievements of the A-11 project, the President said, has been the mastery of the problem of using titanium metal on aircraft.
Great Heats
The aluminum used in today’s airplanes wears out in sustained flight at speeds greater than about Mach 2.2. This is due to the great heats generated by friction as air rushes over the surfaces of the aircraft, particularly the leading edges of the wings.
“The existence of this (A-11) program is being disclosed today to permit the orderly exploitation of this advanced technology in our military and commercial planes,” Mr. Johnson said.
High performance aircraft like the controversial TFX multi-service airplane and the Navy’s Phantom fighter will have speeds up to about Mach 2.5—about 1,600 m.p.h. These high speeds are possible for relatively short duration, however.
Funds for the A-11 were presumably buried in other appropriations, conceivably in part in Air Force appropriations for the B-70.
Dimensions of the A-11 were not revealed although an in-flight picture of the side view of the plane was distributed. It suggests the A-11 is more than 100 ft. long, based on the size of the pilot’s head in the cockpit.
The front half of the A-11 looks very similar to that of the X-15 rocket plane which has flown at speeds over 4,000 m.p.h. The characteristic tail surfaces of the X-15, extending both above and below the fuselage, also were obvious.
The A-11’s engine, a J-58 from Pratt & Whitney, occupies the rear third of the vehicle.
The experimental fire control and air-to-air missile system was developed by the Hughes Aircraft Co. The “A” in the aircraft’s designation suggests an “attack” function.
Number of Questions
Announcement of the project raises a number of questions, some of which Presidential Press Secretary Pierre Salinger answered at a subsequent briefing.
For example, why did the Pentagon object to the Boeing Aircraft Co.’s proposal to use titanium in the TFX if the A-11 had proved that the metal can be used?
“The technical knowledge obtained in the A-11 program made it possible to evaluate Boeing’s proposal,” Mr. Salinger said, and the Pentagon concluded that the titanium in the TFX represented a “High development risk.”
Technical Justification
This seemed to be further technical justification for the choice of General Dynamics over Boeing for the TFX, a choice which raised a political furor in Congress.
The economic meaning of the A-11 was another question put to Mr. Salinger. While the project makes a major contribution to Mach 3 flight, he replied, “It cannot be converted into a transport. A major independent development program is still necessary to produce a supersonic transport.”
—Los Angeles Times, Vol. LXXXIII, Sunday, 1 March 1964, Page 1, Columns 7–8, and Page 6, Columns 3–4
The second Times article identifies the designer as Clarence L. (“Kelly”) Johnson:
NEW PLANE GREAT FEAT OF SECURITY
BY MARVIN MILES
Times Aerospace Editor
President Johnson’s announcement of a new triple-sonic interceptor Saturday disclosed on of the best kept secrets in military annals, a security feat comparable in many ways to that achieved with the atomic bomb.
Apparently even the House Armed Services Committee didn’t know of the project for it recommended $40 million for an improved manned interceptor, a fund approved by the full House just 10 days ago.
The Senate, however, must have had more information, for it made no provision for the new interceptor studies in approving aircraft funding last Thursday, including $52 million for an advanced bomber.
The secret of Lockheed’s new A-11 interceptor was kept far better than that of the same company’s U-2 reconnaissance plane that was eventually shot down on a sky-spy flight over Russia.
Dozens of reports on the mysterious U-2 from various sections of the world had filtered into the news before the international incident over Russia.
The Times learned the new A-11 was spurred by the same aircraft genius who headed development of the U-2 and Lockheed’s famed F-104 Starfighter interceptor, Clarence (Kelly) Johnson, vice president for advanced development projects.
Johnson and his crew work in a carefully-guarded area at the Lockheed Burbank factory known as the “Skunk Works.”
Pierre Salinger, White House press officer, told newsmen the A-11 was funded and managed by the Air Force in the normal manner for a classified project.
Inasmuch as the new plane was started in 1959, this gave rise to speculation as to why a similar plane, the F-108, was canceled in that year.
The F-108 was a North American Aviation project in the same time era that the company’s triple-sonic B-70 bomber was started.
Like the A-11, it was to have had a speed of Mach 3 (about 2,000 m.p.h.) with a range of about 2,000 miles, plus combat time.
Reason for canceling the F-108 was largely budgetary, according to reports in 1959, with the Defense Department declaring that of the two North American projects, the B-70 bomber was a more urgent program than the F-108.
Some estimates of the A-11 can be drawn from the F-108. The North American plane was to have been powered by two engines, and one considered was the Pratt & Whitney J-58, the engine that will power the A-11.
This indicates the new Lockheed interceptor will have two engines also. The J-58 has never been used, either militarily or commercially, as far as The Times could determine. It has a thrust of about 30,000 lb.
Another indication from the F-108 relates to the armament of the A-11. The canceled North American interceptor was to have been armed with Hughes GAR-9 nuclear-tipped rockets.
The A-11 has a Hughes fire control system and its armament could well be the same guided, air-to-air rocket or an advancement of it.
The new interceptor will answer fears expressed by many military experts that Russia’s bomber fleet poses a greater threat to North America than her intercontinental missiles.
The A-11 will have the speed to intercept high speed bombers and shoot them down at ranges that would precluded their launching air-to-ground missiles against U.S. targets.
In appearance, the A-11 looks something like the X-15 rocket plane, a long, slim craft with sharp pointed nose section similar to that of the F-104 Starfighter.
It has both ventral and dorsal fins and appears to be about 90 ft. long over-all.
—Los Angeles Times, Vol. LXXXIII, Sunday, 1 March 1964, Page 1, Columns 7–8 and Page 6, Column 5–6
The YF-12A first flew 7 August 1963.
Clarence L. (“Kelly”) Johnson, Director of Lockheed’s Advanced Development Projects (“the Skunk Works”) with the first YF-12A interceptor, 60-6934. (Lockheed Martin)
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.
Lockheed A-12 Oxcarts and YF-12As at Groom Lake, Nevada. (Central Intelligence Agency)
The YF-12A interceptor is very similar to its A-12 Oxcart and SR-71A Blackbird stablemates. It is 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
Lockheed YF-12A three-view illustration. (NASA)
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.
Hughes AIM-47A guided missile ready for loading into the weapons bay of a Lockheed YF-12A. (U.S. Air Force)
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.
Lockheed YF-12A 60-6936, holder of three World Absolute Speed Records and the World Absolute Altitude Record, at Edwards Air Force Base, California. (U.S. Air Force)
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).
9 October 1999: At a Saturday air show at Edwards Air Force Base, California, NASA Research Pilot Rogers E. Smith and Flight Test Engineer Robert R. Meyer, Jr., flew Lockheed SR-71A-LO 61-7980, NASA 844, on what would be the very last flight of a Blackbird. Although it was scheduled to fly again for the Sunday air show, a serious fuel leak prevented that flight.
61-7980 (Lockheed serial number 2031) was the final SR-71A to be built.
NASA 844 was retired after the final flight and placed in flyable storage, but in 2002, it was placed on static display at the Dryden Flight Research Center,¹ Edwards Air Force Base, California.
¹ In 2014, DFRC was renamed the NASA Neil A. Armstrong Flight Research Center (AFRC).
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.
Lockheed U-2, “Article 341,” at Groom Lake, Nevada, 1955. (Lockheed Martin)
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.
Robert Sieker
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.
The first Lockheed U-2, “Article 341.” (Lockheed Martin)
Lockheed Full Scale Development YF-117A, 79-10780, in three-tone desert camouflage. (Lockheed Martin)
18 June 1981: At 6:05 a.m., Pacific Daylight Time (1305 UTC), the first Full Scale Development Lockheed YF-117A Nighthawk, 79-10780, made its first flight at Groom Lake, Nevada, with “Skunk Works” test pilot Harold C. (“Hal”) Farley, Jr. at the controls. The super-secret airplane was made of materials that absorbed radar waves, and built with the surfaces angled so that radar signals are deflected away from the source.
Harold “Hal” Farley, Jr., with a Lockheed F-117A Nighthawk. (Lockheed Martin)
Hal Farley is a former U.S. Naval Aviator who spent eight years testing F-14 Tomcat fighters for Grumman before going to work at Lockheed’s “Skunk Works.” He flew the Have Blue proof-of-concept prototype and the Senior Trend F-117 program. When he retired from Lockheed, Farley had more that 600 flight hours in the F-117s. His call sign is “Bandit 117.”
Commonly called the “Stealth Fighter,” the Nighthawk is actually a tactical bomber. Five developmental aircraft and 59 operational F-117As were built. They were in service from 1983 until 2008, when the Lockheed F-22 Raptor was planned to assume their mission. They are mothballed and could be returned to service if needed.
A Lockheed F-117A Nighthawk takes off from Nellis Air Force, Base, Nevada. (Lockheed Martin)
The Lockheed F-117A Nighthawk is a single-seat, twin-engine tactical bomber with swept wings and tail surfaces. It is 65 feet, 11 inches (20.091 meters) long with a wingspan of 43 feet, 4 inches (13.208 meters) and height of 12 feet, 5 inches (3.785 meters). The wings’ leading edges are swept aft to 67° 30′. The total wing area is 912.7 square feet ( square meters). The Nighthawk has an empty weight of 29,500 pounds (13,381 kilograms) and a maximum takeoff weight of 52,500 pounds (23,814 kilograms).
The F-117 is powered by two General Electric F404-F1D2 engines. These are two-spool axial-flow turbofan engines which have a 3-stage fan section, 7-stage compressor and 2-stage turbine. They are rated at 10,540 pounds of thrust (46.88 kilonewtons), each. The -F1D2 is 2 feet, 10.8 inches (0.884 meters) in diameter, 7 feet, 3.0 inches (2.210 meters) long and weighs 1,730 pounds (785 kilograms).
The F-117A has a maximum speed of 0.92 Mach (608 miles per hour, 978 kilometers per hour) at 35,000 feet (10,668 meters). The service ceiling is 45,000 feet (13,716 meters) and range is 765 miles (1,231 kilometers), though inflight refueling capability gives it world-wide range.
A Lockheed F-117A Nighthawk drops a 2,000-pound GBU-27 Paveway III laser-guided bomb. (U.S. Air Force)
The Nighthawk has no defensive armament. It can carry two 2,000 pound (907 kilogram) bombs in an internal bomb bay.
Lockheed built 5 YF-117As and 59 production F-117As. The F-117s were retired and placed in climate-controlled storage in 2008.
Scorpion One, 79-10780, is now mounted on a pylon as a “gate guard” at Nellis Air Force Base, Nevada.
Lockheed F-117A Nighthawk in flight. (U.S. Air Force)
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.
