D
Design engineers decided to
mount the nacelles directly
to the underside of the
wings to reduce the landing
gear length and kept the
engines low to the ground
for easy ramp inspection and
servicing. Many thickness variations for the
engine attachment strut were tested in the
wind tunnel and the most desirable shape
for high speed was found to be one which
was relatively thick, filling the narrow
channels formed between the wing and the
top of the nacelle, particularly on the
outboard side.
The prototype 737, a -100 operated by NASA for testing.
Originally, the span arrangement of the airfoil sections of the 737 wing was planned to
be very similar to that of the 707 and 727, but somewhat thicker. A substantial
improvement in drag at high Mach numbers was achieved by altering these sections
near the nacelle. The engine chosen was the Pratt & Whitney JT8D-1 low-bypass ratio
turbofan engine, delivering 14,500 lbf (64 kN) thrust. With the wing-mounted engines,
Boeing decided to mount the horizontal stabilizer on the fuselage rather than the T-tail
style of the Boeing 727.
Production and testing
The initial assembly of the 737 was adjacent to Boeing Field (now officially named King
County International Airport) because the factory in Renton was filled to capacity with
the building of the 707 and 727. After 271 aircraft were built, production moved to
Renton in late 1970. A significant portion of fuselage assembly occurs in Wichita, Kansas,
which was previously done by Boeing but now by Spirit AeroSystems, which purchased
some of Boeing's assets in Wichita.
The fuselage is joined with the wings and landing gear, then moves down the assembly
line for the engines, avionics, and interiors. After rolling out the aircraft, Boeing tests the
systems and engines before its maiden flight to Boeing Field, where it is painted and
fine-tuned before delivery to the customer.
Boeing B737
June 2017
www.alliance-airways.net
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