[ARC5] WWII VHF- Not Ready For Prime Time until Mid-1944.

[David Stinson]

Source Document:

http://www.ibiblio.org/hyperwar/AAF/VI/AAF-VI-3.html

(pp. 104)
At the start of the war both the Atlantic and Pacific coasts had chains of 
radio stations, all equipped with HF. The eastern net consisted of fourteen 
stations and the western of twelve. But coverage expanded rapidly in 1942; 
by the end of the year the Philadelphia Wing had as many radio stations as 
the entire eastern chain had at the time of Pearl Harbor.  **This expansion 
for a time continued to depend upon HF radio** (emp. mine), but as VHF 
equipment became available for tactical units, beginning in the summer of 
1942 (keep reading- ed),
necessary adjustments were made in the fighter control nets. In the last 
half of 1942 extensive projects were drawn up for establishment of a series 
of VHF fighter control areas along the entire west coast and along the 
Atlantic coast from Norfolk north.  Under the new system, regions were 
subdivided into control areas, and in each area a fighter control center 
maintained a separate operations board to direct interceptions. The area 
board displayed the warning data developed by the AWS plus information on 
friendly planes supplied by the VHF net. Three direction finding (D/F) radio 
stations were spaced to form an equilateral triangle with forty miles along 
each side. The stations took simultaneous bearings by picking up a signal 
transmitted by a fighter plane; the exact location of the plane was speedily 
computed by triangulation. Radio contact between controller and interceptors 
was maintained by VHF voice radio through transmitters at the control center 
or at forward relays. At the conclusion of an interception a homing station 
guided the fighters back to base.

**Critical equipment problems seriously delayed the completion of these 
projects** (emp. mine).
The IV Fighter Command secured War Department approval on 6 November 1942 
for a western
VHF net based on six

(pp.105)
control centers, and a comparable east coast project for nine control areas 
was approved on 24 February 1943.
In addition to delays in provision of necessary equipment, there were 
revisions in plans and some difficulty in getting the desired sites;

**the first of the new control centers did not begin to operate until the 
summer of 1944** (emp. mine).

In the end, only three control centers were installed on each coast: in the 
east, on Long Island, in the District of Columbia, and at Langley Field, 
Virginia; on the west coast, at Paine Field to serve Seattle, at Berkeley 
for the San Francisco Bay area, and at North Hollywood in southern 
California.140 Better progress was made in establishing the D/F, relay, and 
homing stations; by May 1944 the last of the obsolete HF stations was 
closed.  When the VHF nets had first been projected, plans called for all 
interceptions to be directed from the fighter control centers. But the delay 
in their establishment forced resort to a hybrid system in which the new D 
/F and homing stations were tied in to control agencies still operating from 
the information centers.
Each air defense wing had at least one fighter control squadron to operate 
its ground-to-air communications. In key areas additional squadrons were 
assigned. Activated originally in the autumn of 1941 as Air Corps Squadrons 
Interceptor Control, these units had been reassigned in January 1942 to the 
particular pursuit group whose numerical designation they bore.  When 
pursuit planes were re-designated as fighters in May 1942, these new units 
became fighter control squadrons. The squadrons operated in scattered 
detachments, one for each radio installation. The usual problems of training 
were aggravated by **the protracted transition to VHF equipment.** (emp. 
mine)