Lockheed U-2
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| Lockheed U-2 | |
|---|---|
 The Lockheed U-2R/TR-1 in flight |
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| Type | High-altitude Reconnaissance |
| Manufacturer | Lockheed Skunk Works |
| Designed by | Clarence "Kelly" Johnson |
| Maiden flight | 1 August 1955 |
| Introduction | 1957 |
| Status | Active: 35 Reserve: 0 ANG: 0 |
| Primary user | United States Air Force |
| Number built | approximately 86 |
The Lockheed U-2, nicknamed Dragon Lady, is a single-engine, high-altitude aircraft flown by the United States Air Force and previously flown by the Central Intelligence Agency. It provides day and night, high-altitude (70,000 ft, 21,000 m plus), all-weather surveillance. The aircraft is also used for electronic sensor research and development, satellite calibration, and satellite data validation.
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[edit] Development
In the early 1950s, with increasing Cold War tensions, the U.S. military required improved strategic reconnaissance to better determine Soviet capabilities and intentions. The existing surveillance aircraft were primarily converted bombers, but they were vulnerable to anti-aircraft artillery, missiles, and fighters. It was thought an aircraft capable of flying at 70,000 feet (21,000 m) would not only be beyond the reach of Soviet fighters and missiles, but would also be outside the range of radar detection.[1] This ability would allow "overflights"—knowingly violating a country's airspace in order to photograph a particular location.
The Air Force gave contracts to Bell Aircraft, Martin Aircraft, and Fairchild Engine and Airplane to develop proposals for the new reconnaissance aircraft. Officials at Lockheed Aircraft Corporation heard about the project and asked aeronautical engineer Clarence "Kelly" Johnson to come up with a design. Johnson was a brilliant designer, responsible for the P-38 Lightning, and the P-80, the first US jet fighter. He was also known for completing projects ahead of schedule, working in a separate division of the company jokingly referred to as the Skunk Works.
Johnson's design, called the CL-282, married long glider-like wings to the fuselage of another of his designs, the F-104 Starfighter. To save weight, his initial design didn't even have conventional landing gear, taking off from a dolly and landing on skids. The design was rejected by the Air Force, but caught the attention of several civilians on the review panel, notably Edwin Land, the father of instant photography. Land presented the proposal to CIA director Allen Dulles that his agency should operate this aircraft. After a meeting with President Eisenhower, Lockheed received a 22.5 million dollar contract for the first 20 aircraft. It was renamed the U-2, with the "U" referring to the deliberately vague designation "utility".
The first flight occurred at Groom Lake test site (aka Area 51) on 1 August 1955, during what was only intended to be a high speed taxi run. The sailplane-like wings were so efficient that as soon as the aircraft hit 70 knots (130 km/h) it jumped into the air.[2]
James Baker developed the optics for a new large format camera to be used in the U-2 while working for Perkin-Elmer. These new cameras were able to provide a resolution of 2.5 ft (76 cm) from an altitude of 60,000 ft (18,288 m).[2]
[edit] Design description
The unique design that gives the U-2 its remarkable performance also makes it a difficult aircraft to fly. [2] It was designed and manufactured for minimum airframe weight, which results in an aircraft with little margin for error.[2] Most aircraft were single-seat versions, only 5 two-seat versions being known to exist.[3]
High-aspect-ratio wings give the U-2 some glider-like characteristics, with a lift-to-drag ratio estimated in the high 20s. To maintain their operational ceiling of 70,000 feet (21,336 m), the U-2A and U-2C models (no longer in service) must fly very near their maximum speed. However, the aircraft's stall speed at that altitude is only ten knots (18 km/h) less than its maximum speed. This narrow window was referred to by the pilots as the "coffin corner". For 90% of the time on a typical mission the U-2 was flying within only five knots above stall, which might cause a decrease in altitude likely to lead to detection, and additionally might overstress the lightly built airframe.[2]
The large wingspan and resulting glider-like characteristics of the U-2 make it highly sensitive to crosswinds which, together with its tendency to float over the runway, makes the U-2 notoriously difficult to land. This results in a required chase car (usually a "souped-up" performance model) that talks the pilot down by calling off the declining height of the aircraft in feet as it decreases air speed in order to overcome the cushion of air provided by the high-lift wings. Instead of the typical tricycle landing gear, consisting of a nose wheel and two sets of main wheels, one under each wing, the U-2 uses a bicycle configuration, with the forward set of main wheels located just behind the cockpit and the rear set of main wheels located behind the engine, coupled to the rudder in order to provide taxi steering. To maintain balance and allow the aircraft to taxi, two auxiliary wheels, called "pogos", are installed in sockets under each wing at about mid-span by ground crew prior to taxiing for take-off. The pogos fall onto the runway surface when the aircraft takes off. The ground crew collects the pogos and re-installs them after the aircraft lands. Skids made of titanium are located on the bottom of each wing tip to protect the "heavy" or downed wing, which occurs because without the pogos in place the aircraft tips to one side once it has slowed down sufficiently during landing. The ground crew installs a pogo in the "light" or up wing while the other crew members use their weight to pull down the light side. Then two of the crew push up the heavy wing, allowing a third crew member to install a pogo on the other side.[4]
Because of the high operating altitude the pilot must wear the equivalent of a space suit. The suit delivers the pilot's oxygen supply and emergency protection in case cabin pressure is lost at altitude (the cabin provides pressure equivalent to approximately 29,000 feet/8,800 m). To prevent hypoxia and decrease the chance of decompression sickness pilots don a full pressure suit and begin breathing 100% oxygen one hour prior to launch to de-nitrogenize the blood; while moving from the building to the aircraft they breathe from a portable oxygen supply.[citation needed]
The aircraft carries a variety of sensors in the nose, Q-bay (behind the cockpit, also known as the camera bay), or wing pods. The U-2 is capable of simultaneously collecting signals, imagery intelligence and air samples. Imagery intelligence sensors include either wet film photo, electro-optic or radar imagery — the latter from the Raytheon ASARS-2 system. It can use both line-of-sight and beyond-line-of-sight data links. One of the most unusual instruments in the newest version of the U-2 is the off-the-shelf Sony video camera that functions as a digital replacement for the purely optical viewsight (an upside down periscope-like viewing device) that was used in older variants to get a precise view of the terrain directly below the aircraft, especially when it was landing.
[edit] Operational history
[edit] United States
Though both the Air Force and the Navy would eventually fly the U-2, it was originally a CIA operation, run through the Office of Scientific Intelligence. Due to the political implications of a military aircraft invading a country's airspace, only CIA U-2s conducted overflights. The pilots had to resign their military commissions before joining the CIA as civilians, a process they referred to as "sheep dipping."[2]
Pilot training in the U-2 was aided by the construction of a pair of two-seat trainer aircraft, modified from the single-seater and designated the CT-2, with the second (trainee) cockpit mounted behind and above the cockpit of the (training) pilot in command.[citation needed]
As often happens with new aircraft designs, there were several operational accidents, some fatal.[5] The first fatal accident was on 15 May 1956, when the pilot stalled the aircraft during a post-takeoff maneuver which was intended to drop off the wingtip outrigger wheels. The second occurred three months later, on August 31, when the pilot stalled the aircraft immediately after takeoff. Two weeks later, a third aircraft disintegrated during ascent, also killing the pilot. There were a number of other non-fatal incidents, including at least one which resulted in the loss of the aircraft.
The U-2 came to public attention when pilot Francis Gary Powers was shot down over Soviet territory on 1 May 1960, causing the U-2 incident.
On 14 October 1962, a U-2 from the 4080th Strategic Reconnaissance Wing, based at Laughlin Air Force Base near Del Rio, Texas, and piloted by Major Richard S. Heyser, photographed the Soviet military installing nuclear warhead missiles in Cuba, precipitating the Cuban Missile Crisis. Heyser concluded this flight at McCoy AFB in Orlando, Florida, where the 4080th established a U-2 operating location for the duration of the crisis. On October 27, 1962, in flight from McCoy AFB, a U-2 was shot down over Cuba by two SA-2 Guideline surface-to-air missiles, killing the pilot, Major Rudolph Anderson.[6] Anderson was posthumously awarded the first Air Force Cross.[7]
In 1963, the CIA tried carrier-based U-2 operations to overcome range limitations. After CIA pilots took off and landed U-2s on the USS Ranger and other ships, carrier-based U-2s were used to monitor French nuclear tests on Moruroa in 1964.[8]
In early 1964, the Strategic Air Command (SAC) sent a detachment of U-2s from the 4080th to South Vietnam for high-altitude reconnaissance missions over North Vietnam. On 5 April 1965, U-2s from the 4028th SRS (Strategic Reconnaissance Squadron) took photos of SAM-2 sites near Hanoi and Haiphong harbor. On 11 February 1966, the 4080th Wing was redesignated the 100th SRW and moved to Davis-Monthan AFB, Arizona. The SRS detachment at Bien Hoa AB, South Vietnam, was redesignated the 349th SRS.[9]
The only loss of a U-2 during combat operations occurred on 8 October 1966, when Major Leo Stewart, flying with the 349th Strategic Reconnaissance Squadron, developed mechanical problems high over North Vietnam. The U-2 managed to return to South Vietnam where Stewart ejected safely. The U-2 crashed near its base at Bien Hoa. In July 1970, the 349th SRS at Bien Hoa moved to Thailand and was redesignated the 99th SRS, and remained there until March 1976.[9]
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In 1969, the larger U-2Rs were flown from the USS America. The U-2 carrier program is believed to have been halted after 1969.
In June 1976, the U-2s of the 100th SRW were transferred to the 9th SRW at Beale AFB, California, and merged with SR-71 aircraft operations there. When Strategic Air Command was disestablished in the early 1990s, the wing was transferred to the new Air Combat Command and redesignated the 9th Reconnaissance Wing (9th RW).
In 1984, during a major NATO exercise, Royal Air Force Flight Lieutenant Mike Hale intercepted a U-2 at a height of 66,000 feet (20,000 m), where the aircraft had previously been considered safe from interception. Hale climbed to 88,000 ft (26,800 m) in his Lightning F3. [10]
The U-2 is still in frontline service more than 50 years after its first flight despite the advent of surveillance satellites. This is primarily due to the ability to direct flights to objectives at short notice, which satellites cannot do. Production was restarted in the 1980s. The U-2 has outlasted its Mach 3 SR-71 replacement, which was retired in 1998. A classified budget document approved by The Pentagon on 23 December 2005 calls for the termination of the U-2 program no earlier than 2011, with some aircraft being retired by 2007.
[edit] Possible retirement
In January 2006, the Secretary of Defense Donald Rumsfeld announced the pending retirement of the U-2 fleet as a cost-cutting measure, and as part of a larger reorganization and redefinition of the Air Force's mission that includes the elimination of all but 56 B-52s and a reduction in the F-117 fleet.[11]
Rumsfeld said that this will not impair the Air Force's ability to gather intelligence, which will be done by satellites and a growing supply of unmanned RQ-4 Global Hawk reconnaissance aircraft. However, Congress has not, as of 2008, passed legislation to retire the U-2 as there is no system able to replace it.
[edit] Republic of China (Taiwan)
Another U-2 operator was the Republic of China (Taiwan), which flew missions mostly over the People's Republic of China (PRC). Since the 1950s, the Republic of China Air Force had used the B-57 aircraft for reconnaissance missions over the PRC, but results were limited by the aircraft's low range and speed. In 1958, ROC and American authorities reached an agreement to create the 35th Squadron, nicknamed the Black Cat Squadron, composed of U-2s.
A total of 27 ROC pilots completed training in the US. In July 1960, the CIA provided the ROC with two U-2s and in December the squadron flew its first mission over mainland China. The objective of the ROC U-2 squadron was to conduct reconnaissance missions assessing the PRC's nuclear capabilities. For this purpose the ROC pilots flew to as far as Gansu and other remote regions in northwest China.
In total, the squadron flew some 100 missions, with five aircraft shot down, including three fatalities and two pilots captured. In 1968, the ROC U-2 fleet was replaced with the newer U-2R. However, with the coming of the Sino-Soviet split and the rapprochement between the US and the PRC, the ROC U-2 squadron stopped entering Chinese airspace, and instead only conducted electronic surveillance over international waters.
During his visit in China in 1972, US President Richard Nixon promised the Chinese authorities to cease all reconnaissance missions over China. This ended the ROC's U-2 operations. In 1974, the two remaining U-2 aircraft in ROC possession were returned to the US. [12]
[edit] Variants
[edit] Primary list
- Sub-section source: AeroWeb[13]
- U-2A
- Initial production, single-seat; 48 built
- U-2B
- Two-seat trainer; 5 built
- U-2C
- Enhanced single-seat model with improved engine and modified engine intakes
- U-2D
- Enhanced two-seat trainer; unknown built
- U-2CT
- Enhanced two-seat trainer rebuilt from U-2D airframes with relocation of the seats; 6 known converted
- U-2G
- A-models modified with reinforced landing gear, added arresting hook, and wing spoilers for US Navy carrier operations; 3 converted
- U-2R
- C-models enlarged and improved with underwing pods and increased fuel capacity; 12 built
- U-2RT
- Enhanced two-seat R-model trainer; 1 built
- U-2EPX
- Proposed US Navy maritime surveillance R-model; 2 built
- WU-2
- Atmospheric/weather research WU-model
- TR-1A
- All new "tactical recon" TR-model based on the U-2R with side-looking radar, new avionics, and improved ECM equipment; 33 built
- TR-1B
- All new two-seat trainer for the TR-1A; 2 built
- ER-2
- Single-seat "earth resource" ER-model for NASA research
- U-2S
- New re-designation for the TR-1A; updated with a improved engine, improved sensors, and addition of a GPS system; 31 converted
- U-2ST
- New re-designated TR-1B two-seat trainer with improved engine; 4 converted
[edit] U-2E/F details
In May 1961, in a little known attempt to extend the U-2's already considerable range, a number of aircraft were modified with aerial refueling equipment. Lockheed began to modify six CIA U-2s and several USAF U-2s with aerial refueling equipment that extended the aircraft's range from approximately 4000nm to over 8000nm and extended its endurance to more than 14 hours. The J57 powered U-2Bs were re-designated U-2E and the J75 powered U-2Cs were re-designated U-2F.[14] Although the modified U-2s were capable of flying for over 14 hours, this took little account of pilot fatigue and although an additional oxygen cylinder was installed on these aircraft, little use was made of this capability. One aircraft was both air refueling and carrier capable and was the only U-2H.[15]
[edit] U-2R/S details
The U-2R, first flown in 1967, is significantly larger and more capable than the original aircraft. A tactical reconnaissance version, the TR-1A, first flew in August 1981. A distinguishing feature of these aircraft is the addition of a large instrumentation "superpod" under each wing. Designed for standoff tactical reconnaissance in Europe, the TR-1A was structurally identical to the U-2R. The 17th Reconnaissance Wing, Royal Air Force Station Alconbury, England used operational TR-1As from 1983 until 1991. The last U-2 and TR-1 aircraft were delivered to the Air Force in October 1989. In 1992 all TR-1s and U-2s (all U-2Rs) were designated U-2Rs. The two-seat trainer variant of the TR-1, the TR-1B, was redesignated as the TU-2R. After upgrading with the F-118-101 engine, the former U-2Rs were designated the U-2S Senior Year.
[edit] ER-2 details
A derivative of the U-2 known as the ER-2 (Earth Resources -2) is based at the Dryden Flight Research Center and is used by NASA for high altitude civilian research including Earth resources, celestial observations, atmospheric chemistry and dynamics, and oceanic processes.
[edit] Operators
- Black Cat Squadron of Republic of China (Taiwan) Air Force
- 99th Reconnaissance Squadron/1st Reconnaissance Squadron USAF Beale Air Force Base, CA. United States Air Force
- 5th Reconnaissance Squadron USAF Osan Air Base, South Korea United States Air Force
NOAA, FEMA, DEA
- Additional operational units are operated from various locations around the world as operational requirements demand.
[edit] Specifications (U-2S)
Data from International Directory,[16] Global Security,[17] USAF Fact Sheet,[18]
General characteristics
- Crew: One
- Length: 63 ft (19.2 m)
- Wingspan: 103 ft (31.4 m)
- Height: 16 ft (4.88 m)
- Wing area: 1,000 ft² (92.9 m²)
- Empty weight: 14,300 lb (6,760 kg)
- Max takeoff weight: 40,000 lb (18,100 kg)
- Powerplant: 1× General Electric F118-101 turbojet, 19,000 lbf (84.5 kN)
Performance
- Maximum speed: 434 knots (500 mph, 805 km/h)
- Cruise speed: 373 knots (429 mph, 690 km/h)
- Range: 5,566 nmi (6,405 mi, 10,300 km)
- Service ceiling 85,000+ ft (25,900 m)
- Flight endurance: 12 hours
[edit] See also
- Black Cat Squadron of the Republic of China (Taiwan)
- Dr. James G. Baker
- SR-71 Blackbird
Comparable aircraft
Related lists
[edit] References
[edit] Notes
- ^ Suggestions re: The Intelligence Value of AQUATONE
- ^ a b c d e f Invention & Technology Magazine, Volume 22, Number 3.
- ^ ABC News:So High, So Fast
- ^ The U-2 World (January 1991 - July 1994, May - October 1996)
- ^ Pedlow and Welzenbach 1992, p. 79-80.
- ^ Major Rudolf Anderson
- ^ Maj. Rudolf Anderson Jr.
- ^ U-2 Aircraft Carrier Operations
- ^ a b Hobson 2001
- ^ Lightning
- ^ "DoD Cuts Air Force Aircraft Fleet", military.com, January 11, 2006.
- ^ Brief History of U-2, Defence International (全球防衛雜誌), Vol. 35 Issue. 5, May 2002, Taiwan, ROC
- ^ AeroSpaceWeb: U-2 Dragon Lady and AeroSpaceWeb: Public Domain Statement
- ^ Polmar, Norman. Spyplane: The U-2 History Declassified, page 173. Zenith Imprint, 2001. ISBN 0760309574
- ^ Lockheed U-2 C / TR-1 / U-2R/S. Retrieved on 2008-01-06.
- ^ Frawley, Gerard. The International Directiory of Military Aircraft, page 107. Aerospace Publications Pty Ltd, 2002. ISBN 1-875671-55-2
- ^ U-2 Specifications, GlobalSecurity.com.
- ^ U-2 Fact Sheet, U.S. Air Force, September 2007.
[edit] Bibliography
- ABC News Correspondent Gets Rare Chance to Fly as Civilian in Spy Plane" ABC News
- Hobson, Chris. Vietnam Air Losses, USAF, USN, USMC, Fixed-Wing Aircraft Losses in Southeast Asia 1961 - 1973. North Branch, Minnesota: Specialty Press, 2001. ISBN 1-85780-1156.
- Miller, Jay. Lockheed Martin's Skunk Works: The Official History... (updated edition). Leicester, UK: Midland Publishing Ltd., 1995. ISBN 1-85780-037-0.
- Pedlow, Gregory W. and Welzenbach, Donald E. The Central Intelligence Agency and Overhead Reconnaissance: The U-2 and OXCART Programs, 1954-1974. Washington, DC: CIA, 1992.
- The World's Great Stealth and Reconnaissance Aircraft. New York: Smithmark, 1991. ISBN 0-8317-9558-1.
[edit] External links
- U-2S/TU-2S USAF Fact sheet
- U-2 page on GlobalSecurity.org
- U-2 page on WorldsAirSpace.com
- First-hand experience of launching the U2
- Black Cat Squadron
- Pentagon To Retire U2 Spy Plane (UPI) 5 January 2006
- A Wild Ride from the Edge of Space (Southwest Texas LIVE!) 17 October 2006
- The Sky Still Burns in Your Memory (Southwest Texas LIVE!) 17 October 2006
- Taiwan Filmmakers creating film about Taiwan's U-2 Blackcat Squadron (Southwest Texas LIVE!) 17 December 2006
- Aviators of Laughlin AFB, Texas (Southwest Texas LIVE!) 26 April 2007
- U2 plane used in the aftermath of hurricane Katrina.
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