FlightGlobal.com
Home
Premium
Archive
Video
Images
Forum
Atlas
Blogs
Jobs
Shop
RSS
Email Newsletters
You are in:
Home
Aviation History
1967
1967 - 0046.PDF
46 FLIGHT International, 12 January AIR TRANSPORT America's SST Choice As RECORDED last week (page 2) the FAA has chosen the, Bodng variable-geometry ("integrated") airframe and theGeneral Electric GE4/J85 afterburning powerplant as winners of the American SST competition. A final decision to go ahead to the prototype construction stage may, however, be delayed, the FAA says, for "several months" while design work proceeds. The selection is said to have been supported by most of the US airlines and by independent technical analyses. So far $311 million (£110 million) has been spent on the development and design of the two airframes and two engines, and $200 million (£72 million) is so far available for the start of prototype construction up to the end of fiscal year 1967 (June 30, 1967). An additional $430 million (£154 million) will, it is expected, be requested by the US Government in the FY 1968 (1967-68) budget. The total cost of building and flight-testing (to lOOhr) of two prototypes is expected to be about $1,000 million (£360 million). The objective is to have the prototypes flying by early 1970 with production deliveries starting in 1974. Boeing has made several major modifications in the SST design in recent months, including a change in low-speed wing- sweep angle and several changes suggested as alternatives to the proposal submitted last September. The incorporation of a direct-lift system, using wing spoilers to decrease or increase lift on the main wing, is proposed; the spoilers would be raised 3° before the start of the approach, and then raised or lowered to provide direct lift control for rate-of-descent adjust- ments. The spoilers would move in conjunction with normal elevator-control surfaces. Boeing proposed this change several months ago. The new wing-angle is 20° (previously 30°) in the unswept position; this increases the aspect ratio for land- ing and take-off. The total elevator-control surface area has been increased to provide greater control power during take-off and landing. This change was added, according to Aviation Week, after wind-tunnel tests showed that the control in pitch was in- adequate with an extreme forward centre of gravity. Boeing has also installed a strain-gauge centre of gravity detection system on the nosewheel with a read-out at the flight engineer's station. This permits the engineer to transfer fuel while taxying, if necessary to return the centre of gravity to a safe part of the range. The supersonic Mach 2.7 cruise lift-drag ratio has been increased from 7.7 to 8.2 following design refinements, in- cluding changes in wash-out and wing-section, together with drag reductions. Finally, the proposed wide-body alternative fuselage has now become the standard version. Footnote: According to Aviation Daily there is little doubt thatLockheed and P&W, the unsuccessful candidates, are eligible for repayments of about $20 million and $15 million respectively. Data: Maximum take-off weight, 675,0001b; maximum payload,75,0001b: passenger capacity, 250-350. Range, with 313 passengers, 4,000 miles plus; normal cruise, Mach 2.7 (1,800 m.p.h. at 64,000ft);FAR take-off at maximum weight (30° sweep), 186 m.p.h., 5,700ft; approach speed and FAR landing field requirement (20° sweep),146 m.p.h. and 5,800ft. Overall length, 306ft; span, 180ft (20° sweep), 174ft (30°), 106ft (72°); wing area, 9,000 sq ft; overallheight, 46ft. _ " • In this recent general-arrangement drawing of the Boeing SST can be seen many of the changes made since the developed version was first illustrated in "Flight" for June 23 (page 1035). See story on this page
Sign up to
Flight Digital Magazine
Flight Print Magazine
Airline Business Magazine
E-newsletters
RSS
Events
