The U-2, America's Secret Airplane

Before reconnaissance satellites, there was the U-2, which flew above 65,000 feet and was at the center of the famous 1960 U-2 incident.
Marcia Wendorf
Original U-2 aircraftSource: Wikimedia Commons

On April 12, 2019, the U.S. Central Intelligence Agency (CIA) released declassified cold war photos taken by its U-2 spy planes. While the photographs are remarkable, the story of the U-2 itself is even more remarkable.


Central Marshes of southern Iraq
Central Marshes southern Iraq

During the cold war following WWII, the U.S. required imagery of the Soviet Union to determine Russian capabilities and intentions. Overflights by U.S. bombers that had been converted for reconnaissance were vulnerable to anti-aircraft artillery, missiles, and fighter jets.

Higher Than 65,000 Feet

In the early 1950s, the U.S. Air Force (USAF) determined that Soviet MiG-17 fighter jets were unable to fly higher than 45,000 feet (13,700 m), and they also determined that Soviet radar, much of it used American equipment that had been acquired during WWII, couldn't see above 65,000 feet (19,800 m). That meant to be invisible, a reconnaissance aircraft would have to fly above 65,000 feet, and no plane that could fly at that altitude existed.

In 1953, the USAF put out a request for proposal (RFP) to three small aircraft companies: Bell Aircraft, Martin Aircraft, and Fairchild Engine and Airplane to build a plane that could fly at 65,000 feet. When officials at the Lockheed Corporation learned of the RFP, they decided to submit their own unsolicited proposal.

Lockheed tasked its best aeronautical engineer, Clarence "Kelly" Johnson, with creating a novel aircraft design. Johnson was unique in that he worked in a separate division of Lockheed called the "Skunk Works". Johnson came up with a design that was beyond unique. The plane had long, slender wings, a shortened fuselage, no landing gear but instead took off form a special cart and landed on its belly, had two snap-on wing supports called "pogos" that maintained balance while taxiing, and had only a single engine. Upon seeing the design of the new plane at a presentation, Strategic Air Command (SAC) General Curtis LeMay, walked out of the meeting.

While the USAF and SAC didn't appear interested in the new plane, the U.S. Central Intelligence Agency (CIA) was. A member of one of its panels, Edwin Land, convinced the CIA to build the plane. Land went on to invent the Polaroid Land Camera.

Using "un-vouchered" government money, the CIA mailed a $1.26 million ($11.74 million today) check directly to Clarence Johnson's home, and Lockheed went to work. Finding conponents for the new plane proved difficult. When Johnson ordered altimeters calibrated to 80,000 feet (24,400 m) from a company whose ordinary altimeters went to only 45,000 feet (13,700 m), the CIA said they were for an experimental rocket aircraft.

To not evaporate at those altitudes, the new plane needed a new low-volatility, low vapor pressure jet fuel. The Shell Oil Company created a fuel known as JP-7, but its manufacture created a nationwide shortage during 1955 of Esso's FLIT insect repellent.

Once completed in July 1955, the CIA gave the project the code name Project Dragon Lady, and named the new aircraft the U-2. It was delivered to the USAF's secret testing facility at Groom Lake, which is better known as Area 51.

The "Coffin Corner"

During a test flight on August 8th, the U-2 reached 32,000 feet (9,800 m), and on August 16th, it reached 52,000 feet (15,800 m), which had never before been reached in sustained flight. On September 8th, U-2 reached 65,000 feet (19,800 m), and thus fulfilled its mission.

View from the cockpit of a U-2
View from a U-2's cockpit

During one test flight a U-2 suffered a flame-out over the state of Tennessee. Due to the plane's remarkable glide characteristics, the pilot calculated that he could reach the state of New Mexico, a distance of over 1,200 miles, to land. Every U.S. air base had sealed orders describing what to do in case a U-2 landed. The commander of Kirtland Air Force Base near Albuquerque, New Mexico opened his orders, welcomed the plane flying in deadstick, and shuttled it quickly inside a hangar. When the space-suited pilot emerged from the aircraft, it caused quite a sensation.

Pressure suit worn by U-2 pilots
Space suit worn by U-2 pilots 

While the CIA controlled the new plane's cameras and film, the USAF sought to control the project. But, to avoid an international incident, U.S. President Dwight Eisenhower refused to allow military personnel to fly the plane. In order to fly it, USAF pilots had to resign their military commissions then join the CIA as civilians. This process was called "sheep dipping", and the pilots were referred to as "drivers" and not pilots.

The new plane's flight characteristics were difficult to say the least. To stay at 70,000 feet (21,000 m) the plane had to fly at a speed very near to its never-exceed speed (VNE), but the difference between the plane's maximum speed and its stall speed was only 10 knots (12 mph; 19 km/h). This breathtakingly small window was called the "coffin corner" because breaching either speed would cause airflow separation at the wings or tail.

Another problem was that because of the high operating altitude, the cockpit was only partially pressurized. This meant pilots had to wear a space suit, and could only eat or drink from squeezable containers. Pilots typically lost 5% of their body mass during an eight-hour mission.

Originally, pilots took with them a suicide pill called the L-pill, that contained liquid potassium cyanide. In December 1956, after a pilot almost mistook an L-pill for candy, the L-pills were placed inside boxes. When the USAF realized the boxes could rupture, they replaced the L-pills with a needle poisoned with shellfish toxin and hidden within a fake silver dollar.

Decompression sickness was also a constant problem for pilots who breathed 100% oxygen for an hour prior to take off. This removed nitrogen from their blood. Since 2001, over a dozen pilots have reportedly suffered the effects of decompression sickness, with nine experiencing permanent brain damage caused by nitrogen bubbles forming in their blood. To avoid that problem, today U-2 pilots exercise during their oxygen pre-breathing.

A "Slight" Miscalculation

In 1956, the CIA realized that it had not accurately assessed the capabilities of Soviet radar. While a U-2 at 70,000 feet was invisible to U.S. radar, it was quite visible to the Soviets, and they took countermeasures. Many U-2 photographs show what appear to be tiny MiG-15s and MiG-17s attempting and failing to intercept the U-2. They appear tiny because they are at a much lower altitude. On some photographs, the MiGs were so thick that they obscured the target.

Knowing that the Soviets were tracking them, Lockheed tried painting the U-2s blue-black to match the darkness of space, and they gave each plane a more powerful Pratt & Whitney engine that increased its maximum altitude to 74,600 feet (22,700 m). On August 5, 1957, a U-2 stationed at Lahore, Pakistan captured the first photographs of the Soviet Baikonur Cosmodrome near the city of Tyuratam. This was something the CIA had not known existed until then.

Afraid of further angering the Soviets, President Eisenhower authorized just one more mission over the Soviet Union that was to take place no later than May 1, 1960. This was because the Paris Summit which included the U.S., U.S.S.R, U.K. and France, was due to take place on May 16, 1960. In a first of its kind, the mission called for the plane to take off from one location, Peshawar, Pakistan, and land in another, Bodo, Norway. The plane would overfly the cities of Tyuratam, Sverdlovsk, Kirov, Kotlas, Severodvinsk, and Murmansk, and it would gather missile, nuclear and nuclear submarine intelligence.

Map of Powers's flight plan
Declassified in 2013 map of Powers's flight plan

The U-2 Incident

The pilot picked for the mission was the most experienced U-2 pilot, with 27 missions under his belt, Francis Gary Powers. The date of the mission was May 1st, but any student of history could have told the CIA that this was not a good idea. May 1st was the important Soviet holiday of May Day, and because of the holiday, there was much less air traffic than usual.

The Soviets began tracking Powers's flight when it was still 15 miles outside their border, and they tracked it for the next four and a half hours. By then, it was over the city of Sverdlovsk where one of three Soviet SA-2 missiles caught up with it at an altitude of 70,500 feet. Amazingly, the plane was not destroyed and Powers parachuted to safety.

Believing that a crash from 70,500 feet was not survivable, the U.S. concocted a cover story, stating that one of its research aircraft had gone missing, and possibly drifted into Soviet territory. Cannily, Nikita Khrushcev remained quiet, letting the U.S. dig itself into a deeper and deeper hole, until on May 7th he revealed that Powers was alive. Not only that, but Powers had confessed to spying on the Soviet Union. At the Paris Summit, Khrushchev demanded a U.S. apology, and President Eisenhower refused.

If captured, U-2 pilots had been told "to tell them everything that they knew" because everything else could be gleaned from the aircraft itself. On August 17, 1960 Powers apologized to the Soviet people, and was sentenced to three years in prison. Then, on February 10, 1962, he was released from prison and exchanged along with American student Frederic Pryor for Russian spy Rudolf Abel at the Glienicke Bridge between West Berlin and Potsdam, Germany.

Rudolf Abel and the exchange for Powers were the subject of 2015's film "Bridge of Spies" with Abel being portrayed by an especially appealing Mark Rylance. The film received six Academy Award nominations including Best Picture and Best Original Screenplay, and won Best Supporting Actor for Rylance.

Following his release, the USAF was reluctant to reinstate Francis Gary Powers, but Powers resolved the issue by going to work for Lockheed as a U-2 test pilot. As for the Soviets, they used the debris of Powers's U-2 to design their own reconnaissance aircraft, which eventually morphed into the MiG-25R.

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