Editing Boeing 2707 (section)

===Refining the design===
The 733-390 would have been an advanced aircraft even if it had been only subsonic. It was one of the earliest [[wide-body aircraft]] designs, with 2-3-2 row seating arrangement at its widest section<ref name="comm">[http://www.flightglobal.com/pdfarchive/view/1967/1967%20-%202245.html "Commercial Aircraft Survey"] {{webarchive |url=https://web.archive.org/web/20161018160332/http://www.flightglobal.com/pdfarchive/view/1967/1967%20-%202245.html |date=October 18, 2016}}, ''Flight'', November 23, 1967, p. 840.</ref> in a fuselage that was considerably wider than aircraft then in service. The SST mock-up included both overhead storage for smaller items with restraining nets, as well as large drop-in bins between sections of the aircraft. In the main 247-seat tourist-class cabin, the entertainment system consisted of retractable [[television]]s placed between every sixth row in the overhead storage. In the 30-seat first-class area, every pair of seats included smaller televisions in a console between the seats. Windows were only {{convert|6|in|mm}} due to the high altitudes the aircraft flew at maximizing the pressure on them, but the internal pane was {{convert|12|in|mm}} to give an illusion of size.

Boeing predicted that if the go-ahead were given, construction of the SST prototypes would begin in early 1967 and the first flight could be made in early 1970. Production aircraft could start being built in early 1969, with the flight testing in late 1972 and certification by mid-1974.<ref name=comm/>

[[File:Boeing SST model.jpg|thumb|Model of Boeing SST]]
A major change in the design came when Boeing added [[Canard (aeronautics)|canards]] behind the nose—which added weight. Boeing also faced insurmountable weight problems due to the swing-wing mechanism, a titanium pivot section having been fabricated with a weight of {{convert|4600|lb|kg}} and measuring {{convert|11|ft|m}} long and {{convert|2.5|ft|cm}} thick,<ref>{{cite magazine |author=Scholin, Allan R. |title=Aerospace World |magazine=Air Force and Space Digest |publisher=Air Force Association |place=Washington, D.C. |date=March 1969 |volume=50 |number=3 |page=37}}</ref> and the design could not achieve sufficient range. Flexing of the fuselage (it would have been the longest ever built) threatened to make control difficult.  In October 1968, the company was finally forced to abandon the variable geometry wing.<ref>{{Cite web |url=http://www.flightglobal.com/pdfarchive/view/1971/1971%20-%200477.html |archiveurl=https://web.archive.org/web/20161021071633/http://www.flightglobal.com/pdfarchive/view/1971/1971%20-%200477.html|url-status=dead|title=flightglobal.com|archivedate=October 21, 2016}}</ref><ref>{{Cite web |title=flightglobal.com|url=http://www.flightglobal.com/pdfarchive/view/1968/1968%20-%201331.html |archiveurl=https://web.archive.org/web/20161021072129/http://www.flightglobal.com/pdfarchive/view/1968/1968%20-%201331.html |url-status=dead |archivedate=October 21, 2016}}</ref> 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''. Work began on a full-sized mock-up and two prototypes in September 1969, now two years behind schedule.

A promotional film claimed that airlines would soon pay back the federal investment in the project, and it was projected that SSTs would dominate the skies with subsonic jumbo jets (such as Boeing's [[Boeing 747|747]]) being only a passing intermediate fad.

By October 1969, there were delivery positions reserved for 122 Boeing SSTs by 26 airlines, including [[Alitalia]], [[Canadian Pacific Airlines]], [[Delta Air Lines]], [[Iberia Airlines|Iberia]], [[KLM]], [[Northwest Airlines]], and [[World Airways]].<ref>[http://www.flightglobal.com/pdfarchive/view/1969/1969%20-%202894.html "Go ahead for the Boeing SST?"] {{webarchive |url=https://web.archive.org/web/20161021071624/http://www.flightglobal.com/pdfarchive/view/1969/1969%20-%202894.html |date=October 21, 2016}}. ''Flight International'', October 2, 1969.</ref>