Boeing-2707 SST - Supersonic Marvel, Largely Forgotten Today
Capable of transporting 296 passengers across the ocean at 2900 km/h. - 40 years ago, in 1968.
The Sixties were simply amazing times for fascinating technology development. In the automotive industry, the "American dream" of a powerful full-size car was still very much alive. In space exploration, we reached out to the Moon. In air travel, the dream of a supersonic passenger plane seemed almost certain to become reality. Witness "Boeing-2707" SST (Supersonic Transport):
(images credit: Testpilot.ru)
America enters the race... Well, it was good while it lasted
It all started in 1952 with small-scale studies of SST designs by Boeing, but things heated up significantly when in 1962 the governments of Britain and France decided to join efforts in the creation of a supersonic "Concorde" airplane. The intrepid Russians also came up with the Tu-144 (no less capable, but plagued by accidents). The American government nearly panicked and responded with its own program SCAT (Supersonic Commercial Air Transport) in 1963, which got endorsement from President Kennedy himself. The race for dominating supersonic airways was on. (At that time it was believed that all future commercial aircraft would be supersonic). The goal was to produce a commercial aircraft capable of carrying 250 passengers (twice as many as the Concorde) at Mach 3 speed and a trans-Atlantic range of 4,000 miles. Such was the dream, loftier than the European projects, which energized American designers and manufacturers, almost on par with the idea of reaching the Moon.
Boeing 733 - from "delta wing" to "swept wing" design
The proposed plane would be almost twice as large as the Concorde, cost two times more and require twice as much time to build, but it would be the "American Dream" plane, the future of the world's airways (FAA estimated 500 of such planes in use by 1990)
Some initial concepts from the 50s:
Conceptual development of wing geometry (with variations on delta-wing and swing-wing themes):
(image courtesy of NASA)
The variable geometry wing already had quite a history in US (read this article), plus there was considerable data accumulated by the military in developing the XB-70 "Valkyrie" strategic bomber and YF-12 «Blackbird» spy plane. Engineers of the new Boeing plane boasted that European supersonic aircraft is based on already nearly obsolete technology, and while American model may not be the first, it will certainly end up to be the best.
Air tunnel testing of Boeing 733 model:
Some of these concepts looked like F111 fighters with variable geometry wings (a legacy from the TFX program), the others could pass for the upcoming Rockwell B-1 bomber. Some progress was being made, but Boeing did not enjoy a monopoly on SST research for long - in 1964 the government started a competition for preliminary designs: "Boeing" and "Lockheed" were chosen, but "North American" (responsible for the X-15 Rocketplane) was strangely declined. Thus, two giant corporations were pitched against each other, and the design race nicely heated up.
Lockheed 2000 - an honorable mention.
This baby was admirably full-size: some models could transport up to 300 passengers with range of 3500 miles. The Lockheed mock-up was proudly presented to the judges in 1966, but rival Boeing-2707-100 already could take that many passengers and more, with better aerodynamics and less noise pollution. Boeing emerged the sole winner of the government contract.
(images courtesy of Lockheed)
Note: Space helmets on cute stewardesses were all the rage back then. See our previous article Glamour in the Skies for some Braniff helmeted uniforms, designed by Emilio Pucci.
Boeing 2707-100: growing longer and sleeker...
With engines now in the tail section (removed from under aircraft's body due to safety concerns), "Boeing 2707" still featured variable geometry wing and a distinctive two-hinged "droop-nose" - added for the best visibility during takeoffs and landings (its extra joint ensured better ground clearance). A new name reflected the fact that the plane's speed was Mach 2.7. It was decidedly bigger airplane, too.
Boeing 2707-200: almost there...
New 2707 had a tailed delta wing all over again - ironically, just like the rejected Lockheed entry. By October 1968 it was decided to abandon the variable geometry wing due to overwhelming technical problems. However, 2707-200 again grew in size, reaching (some say) truly monstrous proportions. To me it looks more like a futuristic "dream come true".
Delta Airlines Artist Conception of swing wing 2707 design
(images credit: Boeing)
Boeing 2707-300: already 2 years behind schedule...
The new design was smaller, seating "only" 234. Two prototypes were approved by President Nixon in 1969, and it was projected that SST would dominate the skies, rendering all other subsonic aircraft obsolete.
Length: 306 ft (1968) 318 ft (1972)
Wingspan: (1968) 174 ft extended 106 ft swept
Cruising speed: Mach 2.7 or 1,800 mph
Weight: (1968) 675,000 lb
Altitude: More than 60,000 feet
Power: Four GE4 turbojets
Range: Transpacific, 4,000 mi
(images credit: Hiller Aviation Museum)
(photos courtesy: Ben Wang via Airliners.net)
Soon, however, the project began to gather adverse publicity. The biggest complaint was "environmental/ noise pollution", such as sonic booms and reduction of the ozone layer. These concerns surprisingly gained a lot of weight in the government, with supersonic flights over land in the United States eventually completely forbidden. Also, at speeds above Mach 2.2 the aircraft would encounter "skin friction effect" and its body will have to be built out of either stainless steel or titanium, significantly increasing the price. The government (troubled by the Vietnam war) decided not to spend additional millions of dollars and completely cut the funding in 1971.
According to Wikipedia: "The SST became known as "the airplane that almost ate Seattle." Boeing was a major economic force in the region, and was stretched so thin that a billboard was erected that read, "Will the last person leaving Seattle - turn out the lights?"
Extreme costs in operating supersonics brought the whole idea to an unfortunate end, with the beautiful Concorde resting in a museum, and the skies dominated by sluggish, yet fuel-efficient subsonic jets. The dream still remains only a dream... but consider one interesting fact: when the government withdrew the funds for SST program, money (over a million dollars) poured in from American schools & kids. Well, children's enthusiasm could not save the project either.
"The High-Speed Research (HSR)"
program was canceled by NASA in 1999:
(image credit: NASA)
"Concorde" resides in a museum (appropriately in Seattle):
NOTE: one of the most glamorous flights of French Concorde was during the full solar eclipse in 1973 - as a flying scientific laboratory.
This page has a few more pictures.
(image credit: NASA)
But it's not the end of the story:
Meanwhile in the remote & mysterious Russia...
TU-444 keeps the dream alive, and then some.
The Soviet Tu-144 was the first commercial SST aircraft flown (built almost entirely with KGB & military technology). It was withdrawn after a short time due to crashes and problems, but not before making Europeans and Americans accelerate their own projects. Today, Tupolev Aircraft Design Bureau seems to keep the project alive and plans to come up with next-generation Supersonic Transport -
Tu-444. Have a look:
(images credit: Tupolev.ru)
Some say that modern travelers are able to get anywhere on the globe within 24 hours anyway, so it's pointless trying to improve their flight times with expensive SST - but apparently people at Tupolev's are still excited by the idea of getting from Moscow to New York - and back! - in a day. The dream may live on, but the times when the governments raced each other to achieve a shared dream, are over.