The American Concordes that never flew

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The American Concordes that never flew

It was one of the most ambitious aircraft design projects in history, so what happened to the US plans to master supersonic passenger flight?

By Stephen Dowling
22 March 2016
BBC

Excerpts:

US president John F Kennedy rose to this sudden challenge; the Anglo-French Concorde would have competition. America would create its own rivals to the European design, building a giant, passenger-carrying jet capable of flying faster than a rifle bullet.

Concorde, it turned out, was not the only reason to focus American attention. On the other side of the Iron Curtain, the Russian design bureau Tupolev was also creating a supersonic transport and airliner, the Tu-144. To be beaten in the supersonic airliner arena by the British and the French was one thing – to be shown a clean pair of heels by the Russians was another.

President Kennedy’s carrot to Lockheed and Boeing was that the government would pick up 75% of the cost of the programme if either could produce a design that could rival Concorde. Both companies had done private research – “paper studies” as they’re known – on supersonic transport since the late 1950s. Most of these studies mirrored the Russian and European research, creating delta-winged aircraft.

The triangular shape of delta wings provided a stability that could withstand the stresses of enormous speed – aircraft like the French Mirage III fighter and the Russian MiG-21 had already proven the delta shape could easily go to Mach 2 and beyond.

Lockheed chose the delta layout for their design, intended to fly at 2,000mph (3,200km/h) while carrying 270 passengers.

Boeing chose what’s known as ‘variable geometry’ – or swing wings, as they became known – in their initial design. The wings would be straight at low speeds, improving the aircraft’s handling at take-off and landing, and then swing back closer to the aircraft’s body as it picked up speed.

National pride was at stake. But the political will wasn’t enough to solve the enormous design challenges to get Boeing’s swing-wing giant into the air.

Even when the designers moved to a delta wing shape, says Mitchell, they still couldn’t solve some of the weight problems which meant the aircraft was very fuel hungry and couldn’t get from the US to Europe on internal fuel.

And despite the project’s failure, some of the things Boeing learned made its way into other experimental vehicles the aerospace giant built in the following decades, including some of the unmanned vehicles built in recent years, such as the High Speed Civil Transport project during the 1990s. And the super-critical wing, a design tweak now routinely used on modern airliners to limit shockwaves and reduce drag, came out of the 2707 project.

Lockheed’s ill-fated L-2000 design will live on, in a way, thanks to the collaboration with Nasa and Lockheed to fly an experimental demonstrator to research the supersonic aircraft of the future.

The announcement of the Anglo-French Concorde concerned the US (Credit: Getty Images)

The Lockheed L-2000 was one of two designs that underwent more detailed testing (Credit: San Diego Air & Space Museum)

The 2707 project was Boeing’s major priority during the late 1960s (Credit: Boeing)

A full-size mock-up of the delta-winged Boeing 2707 was built in Seattle (Credit: Boeing)

Nasa and Lockheed will collaborate on a new supersonic demonstrator (Credit: Nasa)