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This wind tunnel was designed in 1965 primarily to A 9000 hp Westinghouse electric motor furnishes power
strengthen further Lockheed’s position in the field of V/STOL to the wind tunnel fan. The air cooled main drive motor
and low speed testing. This design effort was completed in is housed inside a faired nacelle in the return section of the
the fall, and contractors were selected for the several sec­ wind tunnel. A large access hatch is provided in the roof
tions of the facility at the end of 1965. The construction of of the wind tunnel structure for installation and major ser­
the Low Speed Wind Tunnel shown in Fig. 5 began in early vicing of the main drive motor and its components. The
1966 and the initial run was made on June 5, 1967. Since motor speed may be varied from 15-330 rpm, and main­
that time, checkout and calibration of the several major tained within ±0.33rpmby using a liquid rheostat in conjunc­
subsystems have been in progress, and scheduled testing has tion with an eddy-current brake. Coarse-speed control of
kept the facility busy since March 1968. the main drive system is accomplished by changing the po­
The Low Speed Wind Tunnel, erected by Chicago Bridge sitions of the liquid rheostat electrodes. The eddy-current
and Iron Co., is an atmospheric static pressure, horizontal brake is used to initiate small changes in load as required
single-return, closed throat system having a circuit center- for precise speed regulation. A viscous damper is included
line length of 780.5 ft. The facility has two major dis­ in the system to avoid critical shaft speed problems through­
tinguishing features: out the range of operation.
1. It incorporates large size tandem test sections par­ The primary speed control station is located on the power
ticularly designed for testing V/STOL configurations in the section of the console in the main control room. Starting
upstream section and for testing low speed models in the and stopping of the drive motor and adjusting the speed
downstream section. throughout the desired range are initiated, as are all major
2. It has a rapid data acquisition and presentation capa­ items in the facility, from this, console seen in Fig. 6.
bility. The main drive motor is coupled directly to the fixed-
The test sections of the Low Speed Wind Tunnel are lined pitch 6-bladed fan which is laminated Sitka Spruce. The
with plywood as a working surface, and the walls are struc­ fan, as shown in Fig. 7,has a hub diameter of 15.6 ft and a
turally positioned by steel formers. The V/STOL test sec­
tion is 30 ft high, 26 ft wide, and 63 ft long, and the low
speed section is 16.25 ft high, 23.25 ft wide, and 43 ft long.
The rear test section has a 7 x 10 height to width ratio to
simplify determination of wind tunnel wall effect correc­
tions. The roof and floor of each test section are parallel,
while the side walls diverge slightly to account for boundary
layer growth. Each test section has full-height adjustable
slots located in the sidewalls at the downstream ends to vent
the in use section to atmospheric pressure. The clear test
section speed range in the V/STOL test section is approxi­
mately 10-125 mph. One in. thick "bullet proof" observa­
tion windows are located in the sidewalls of each test sec- Fig. 6 - Control console
tion. Each test section also has windows located in the
o eilmg panels.
Access to each test section is normally through personnel ^^9999999^^11888
doors at each test section floor level on the control room
side of the wind tunnel and large equipment doors at each
test section floor level.on the opposite side of the wind tun­
nel. Removable roof sections 16 ft in diameter provide over­
head access to the V/STOL and low speed test sections. An
electrically powered 7-1/2 ton crane facilitates moving
heavy articles in and out of the test sections. Full scale
models of other than compact size cars would be lowered
into the test section through the roof access portion.
A four story building fabricated by the general contrac­ U
tor, George A-. Fuller Co., encloses the test section portion
of the wind tunnel.. The test building is heated and me­
chanically ventilated. Office and control room areas are
air conditioned. The wind tunnel circuit structure outside
the main building is cooled when necessary by spraying ap­
proximately 7000 gal of water per minute on the upper ex­
terior surface. This water is collected in a concrete catch
basin and recirculated. Fig. 7 - Main drive fan