Historic California Posts, Camps,
Stations and Airfields
Point Conception Radar Site J-31
A World War II Army Air Forces aircraft
warning station located on what is today Vandenberg AFB.
Wave Aircraft Detector and Ground Control Intercept (CGI) Radar
Fixed medium-range, long wave aircraft detector and GCI. Provides
azimuth, range, and altitude data. Type HR and PPI scopes.
To give continuous plan position and accurate relative height
of enemy plane and friendly fighter plane for GCI. Set can also
be used for early warning and to give increased coverage at low
angles of search. IFF equipment RC-188 is used. When operating
as GCI, VHF equipment SCR-624 is required.
Performance and Siting: Maximum range on a medium bomber, with set on flat
sea level site:
*Range of PPI limits GCI operation
to about 45 miles.
When operating as GCI, set must be sited
so that a flat unobstructed surface extends at least 1/4th mile
in the height-finding sector. Good GCI sites are extremely rare.
For early warning, sets should be sited between 100 and 1,000
feet above an unobstructed surface. Transportability: Set is packaged for shipment in 55 units,
weighing a total of 54,000 lbs. Largest unit measures 15.3' x
3.8' x 1.8'. Total shipping space is 3500 cu. ft.
Requires a weatherproof building approximately 20' x 40' for
housing radar components and a building approximately 20' x 20'
for power units and switchboard. A 25' tower on concrete footing
is required for support of antenna. Buildings and tower can be
built by Engineers in about 3 weeks. Radar can be installed by
5 men in 2 weeks.
8 men are operating crew. For 24-hour operation about 54 men
are required to run radar, communication radio, and camp.
4 KW at 230 volts and 1 KW at 115 volts, from three PE-198 electric
diesel units, supplied with set. (Two units operate simultaneously).
Fuel consumption is 21/2 gals. of Diesel fuel oil per hour.
Department Inventory of Owned, Sponsored and Leased Facilities,
Mobilization (Quartermaster Corps 700-Series
or Corps of Engineers 800-Series):
Theater of Operations: 65
Cost to Government Since 1 July 1940:
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