[ARC5] ARC-5/SCR-274 Navigation Receivers?

[Jack Antonio]

That system would have been the AN/ARA-8 homing system.

 From what I've been able to gather, this system saw service in the
Pacific in the later stages of the war, where it was referred to as
the "Uncle/Dog" system, and was used  post war. It
was primarily used to simplify navigation for escort fighters for
the B-29 effort against Japan.

So far, I've only come across documentation that it was installed
in P-51s during the war, but there's no reason that P-47s couldn't
have had the system as well.

I came across a photo of a P-51H, in USAF markings with the
dual antennas, which indicates that it was still being used at least
until 1948, and have information on an antenna for the system for an
F-80 or similar high speed aircraft. This used two antennas buried on
each side of the vertical stabilizer.

This was a homing system that used two vertical antennas on the aircraft,
with a phasing harness and a relay that selected one of two feed points, 
basically
a lobe switching system. The pilot either heard a Morse D or Morse U if 
not flying
directly at the source, merging into a steady tone when flying directly 
at or away
from the source.

It used the aircraft's communication radio, with a separate relay to 
switch between
the communication antenna and the dual antenna array.  It did require 
the source
transmitter to be keyed continuously. The control panel in the aircraft 
had a mode
to lock its transmitter on the air, so that it could be the source of 
the homing signal, so
that other aircraft could home on it. There also was ingenious method 
that allowed
it home on an unmodulated carrier as well.

Related more to the subject, I also came across a document recently, 
dated September 1948, for F-51D and TF-51D,
that details the replacement of SCR-522, BC-1206, and AN/APS-13, by the 
AN/ARC-3
and BC-453-B.

The last page of this document says that due to shortage of AN/ARC-3, 
the installations
of AN/ARC-3 are to be discontinued.

Jack Antonio WA7DIA/4







On 4/30/2011 12:08 PM, Mike Morrow wrote:
>> It looks like, during WW2, the P-51 and the P-47 had a VHF homing system
> And that system was what???  The P-47 and -51 were USAAF aircraft, and