Imagine driving a car whose engine cuts out if you drive it only a few miles below its maximum speed. A car so finally balanced that placing your coffee cup on anything other than the cup holder could cause it to swerve uncontrollably. You have to drive it – for anything up to 15 hours – in a diving suit. And when it comes to parking you can’t look out the windows, but have to rely instead on the directions of another driver guiding you to your destination from another car.

Congratulations – you might just make it as a Lockheed U-2 pilot.

The U-2 was one of the Cold War’s most infamous aircraft, a plane designed to fly over unfriendly territory too high for enemy fighters or missiles, and take pictures of unparalleled detail - and, as it has just been revealed, helped spur the development of the secret Area 51 airbase.

Designed less than 20 years after most air forces were still fielding biplane fighters, the U-2 flew at the edge of space, using cameras that could render detail down to two-and-a-half-feet from a position 13 miles (21km) above the Earth’s surface. When Top Gear and Headsqueeze presenter James May flew in a U-2 (video above), gazing at the view 70,000 feet [21.3km] up with the blackness of space above him, he and the plane’s pilot, Major John Cabigas, were the second-highest humans on the planet. Only the astronauts on the International Space Station, wheeling above the Earth some 250 miles (400km) above sea level, were higher.

The ability to fly at such altitudes is only one item on the U-2’s remarkable CV. Here BBC Future recounts some of the other amazing facts and history about one of aviation’s most intriguing designs.

No U-2, no Area 51

Built on the edge of a dry lakebed in the arid desert of Nevada, the mysteriously named Area 51 has long been a magnet for conspiracy theorists and UFO enthusiasts. The conspiracy theory was that an alien spaceship had crashed at the site, and that alien technology was then used to create some of the US Air Force’s more outlandish designs, such as the F-117 stealth fighter. The US military kept a resolute silence over the subject until this week, when it announced that the airfield was specifically built to test Lockheed’s U-2. A secret 1992 internal CIA history of the U-2 programme was originally declassified in 1998 with heavy redactions. But many of the formerly secret elements were made public after a records request by the National Security Archive at the George Washington University in Washington DC. CIA and Air Force staff chose the site after an aerial survey, and President Eisenhower himself signed the order. The U-2 – flying too high for aircraft of the time, supposedly – may have been behind a spate of UFO sightings.

They helped avert a deadly arms race in the 1950s…

Before the U-2, taking reliable pictures of the Soviet Union was a daunting task. The sheer size of the country made it difficult to locate secretive sites, while aircraft snooping on the country’s border were in danger of being intercepted by the USSR’s aggressive air defences.

In the mid-1950s, Soviet premier Nikita Krushchev warned the US that the USSR was making missiles “like sausages” and shows of strength at events such as the 1955 Moscow Air Show made it seem that Soviet bomber factories were working round the clock. The details of the communist state’s armament production were a mystery until the first U-2 flight from Germany in 1956. As Lockheed’s own blog on the U-2 states, it soon became apparent that the vast Russian steppes were not crammed with bomber factories, but were mostly assembling tractors. This vital intelligence meant US president Dwight D Eisenhower stepped back from a massive arms race which could have led to nuclear confrontation.

… but also almost caused the Cold War to turn hot

On 1 May 1960, a CIA U-2 piloted by Gary Powers took off from Peshawar in Pakistan on a mission to photograph the closed city of Sverdlovsk (now Yekaterinburg), before flying north across to the USSR to land in Norway. A Soviet missile battery near Sverdlovsk had other ideas – Powers’ aircraft was hit and the pilot was forced to eject, and was held prisoner by the USSR for two years.

Worse was to come two years later; during the Cuban Missile Crisis, when the US blockaded Cuba after discovering preparations to house Soviet ballistic missiles, a U-2 undertaking aerial reconnaissance over Cuba was downed, again by a Soviet surface-to-air missile. US forces went on high alert, though cooler heads prevailed, preventing armed conflict that could have ended in nuclear war.

U-2 pilots dress like spacemen… and suffer the bends

Much like their spyplane compatriots in Lockheed’s faster-than-a-bullet SR-71 Blackbird, the U-2 pilots were flying so high that normal flight suits were not enough; any cockpit decompression would have resulted in almost instant loss of consciousness. U-2 pilots are housed in spacesuits, ones which include feeding tubes to sustain them on hour-long missions; early version of the suits were essentially prototypes for those worn by Space Shuttle crews.

U-2 pilots, carrying out missions in pressurised suits for anything up to 12 hours at a time, have started developing a debilitating sickness not dissimilar to the bends – the potentially life-threatening condition deep-sea divers get when they ascend too quickly. Pilots now have to breathe pure oxygen before they start their missions to remove some of the nitrogen in their system.

Massive wingspan, tiny wheels

The U-2’s enormous wingspan is what helps give it the lift needed to stay afloat miles above the ground – it measures 103ft (31.4m) from tip-to-tip. But when it comes to landing it proves very tricky indeed. The pilot’s job is made trickier in that the aircraft’s design is so honed to keeping it in the air that the plane will only land when the wing is fully stalled, and the lack of electrically-powered controls makes the plane very physically demanding at lower altitudes. The pilot’s cockpit position, also makes it very hard to judge the plane’s distance from the ground, and there’s another problem – the undercarriage. Unlike most planes, the U-2 does not boast three-wheel undercarriage, but instead has two main landing gears located at the front and back of the aircraft, like bicycle wheels. The landing procedure is so precarious that U-2s are accompanied by a fellow pilot following the plane in a chase car, and giving him directions via a radio. The fun doesn’t end there; when the plane comes to rest it’s with one wingtip scraping along the ground. The wingtips are reinforced with special landing skids to take this into account.

U-2s hunt for roadside bombs in Afghanistan

The plane’s days of snooping for Soviet missile bases have long gone – U-2s are now used for less partisan work, performing atmospheric tests for Nasa. The U-2 still serves the US military, but in a manner not envisaged when it was designed by Lockheed in the 1950s. Some of the US Air Force’s remaining 32 U2’s patrol the skies above Afghanistan from a base in the Persian Gulf, in direct radio contact with troops on the ground. Its updated sensors can detect tiny traces in disturbed earth, allowing them to warn approaching troops of possible roadside bombs – all from 70,000 feet. On top of that, the plane’s lofty height has also proved useful in picking up mobile phone chatter by insurgents, which is difficult to intercept on the ground.

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