SST Development: Variable Wing Sweep with a Free-Flying Supersonic Transport ~ 1967 NASA Langley Research Center (Patreon)

more at http://quickfound.net/

'The test demonstrates an  in-flight demo of variable wing sweep with a free-flying Supersonic Transport configuration.  The wing sweep angle is varied between 25 degrees and 75 degrees.  The inboard portion of the wing is fixed and the panels are pivoted about a point well outboard of the fuselage.  The test was conducted in both NASA Langley Research Center's Free Spinning Tunnel and Full Scale Tunnel.  Langley Film #L-644.'

Originally a public domain film from NASA, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied.

The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original).

https://en.wikipedia.org/wiki/Boeing_2707

Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/

The Boeing 2707 was the first American supersonic transport (SST) project. After winning a competition for a government-funded contract to build an American SST, Boeing began development at its facilities in Seattle, Washington. The design emerged as a large aircraft with seating for 250 to 300 passengers and cruise speeds of approximately Mach 3. It was intended to be much larger and faster than preceding SST designs such as Concorde.

The SST was the topic of considerable concern within and outside the aviation industry. From the start, the airline industry had noted that the economics of the design were questionable, concerns that were only partially addressed during development. Outside the field, the entire SST concept was the subject of considerable negative press, centered on the issue of sonic booms and effects on the ozone layer.

A key design feature of the 2707 was its use of a swing wing configuration. During development the required weight and size of this mechanism continued to grow, forcing the team to start over using a conventional delta wing. Rising costs and the lack of a clear market led to its cancellation in 1971 before two prototypes had been completed...

Boeing had worked on a number of small-scale supersonic transport (SST) studies since 1952. In 1958, it established a permanent research committee, which grew to a $1 million effort by 1960. The committee proposed a variety of alternative designs, all under the name Model 733. Most of the designs featured a large delta wing, but in 1959 another design was offered as an offshoot of Boeing's efforts in the swing-wing TFX project (which led to the purchase of the General Dynamics F-111 instead of the Boeing offering). In 1960, an internal competition was run on a baseline 150-seat aircraft for trans-Atlantic routes, and the swing-wing version won...

In November 1962, still to the surprise of many, the Concorde project was announced...

Three days after the Concorde announcement, Halaby wrote a letter to Kennedy suggesting that if they did not immediately start their own SST effort, the US would lose 50,000 jobs, $4 billion in income, and $3 billion in capital as local carriers turned to foreign suppliers...

Requests for Proposals were sent out to airframe manufacturers Boeing, Lockheed, and North American for the airframes; and Curtiss-Wright, General Electric and Pratt & Whitney for engines. The FAA estimated that there would be a market for 500 SSTs by 1990...

Boeing's entry was essentially identical to the swing-wing Model 733 studied in 1960; it was known officially as the Model 733-197, but also referred to both as the 1966 Model and the Model 2707. The latter name became the best known in public, while Boeing continued to use 733 model numbers internally. The design resembled the future B-1 Lancer bomber, with the exception that the four engines were mounted in individual nacelles instead of paired pods used on the Lancer. The blended wing root spanned almost all of cabin area, and this early version had a much more stubby look than the models that would ultimately evolve. The wing featured extensive high-lift devices on both the leading and trailing edges, minimizing the thrust required, and thus noise created, during climb out. The proposal also included optional fuselage stretches that increased capacity from the normal 150 seats to 227.

Lockheed's entry, designated CL-823, was essentially an enlarged Concorde...

The North American NAC-60 was essentially a scaled-up B-70...

In October 1968, the company was finally forced to abandon the variable geometry wing. The Boeing team fell back on a tailed delta fixed wing. The new design was also smaller, seating 234, and known as the Model 2707-300...

In March 1971... the U.S. Senate rejected further funding... the House of Representatives also voted to end SST funding on 20 May 1971...