[ARC5] More on the "No HF" Myth

[David Stinson]

> Is there much information out there about the use of the HF
> command sets (principally, the SCR-274-N) 
> in the European Theater of Operations (ETO)?

It is very important to remember that we cannot make 
blanket statements about "this was always done"
and "that was never done."  Neither statement is correct.
There are numerous exceptions documented in the photographs,
in equipment installation and operation documents and
in oral histories.

I have not yet found direct written orders saying 
"you will use your HF command set to communicate 
with other aircraft on this mission,"  
but that's not surprising.
I do have many pieces of training documents,
filled-out workbooks and other material dated 1944/45
that concern SCR-274N.  My "Radio Operator's Information File,"
updated to November 1944
says Command sets were "used by the pilot for plane to plane
and plane to ground communications."  Since we've established
that unless you were a fighter on a tactical mission in the ETO
you needed HF in your aircraft, it's reasonable to conclude
that HF was installed and was used.
The Radio Operator's Information File contains 
12 pages on SCR-274N, followed by 10 pages on SCR-522.
The cover page on the Command Set chapter shows two P-47 fighters.
An aside: NTSch Line Maintenance- Electronic Equipment
for the PB4-Y Navy patrol bomber which patrolled the 
North Atlantic.  It contains AN/ARC-5 and ATB/ARB HF command equipment
and AN/ARC-5 VHF command equipment.  Such an aircraft
could net get along without HF Command capability.

TM 1-460 "Radio Telephone Procedure Army Air Forces,"
paragraph 107 "Army air-ground" states: 
"4495 kilocycles is the assigned frequency to be used 
by Army aircraft."  Paragraph 112 lists Army Airways as 4220 KC.
It's hard to imagine these freqs would be assigned and not used.
It's harder to imagine the radio ops defying these written 
orders, as well.

Moreover, photographic evidence proves conclusively
that HF comm equipment did see combat use in the ETO 
and in North Africa.  Somewhere in this disorganized 
mess is a photo of General Patton standing next to his
personal transport aircraft in North Africa.  
It has RCA HF installed.  I have other such photographs.

We can generally say that large aircraft talked to 
each other using HF and, late in the war, had a SCR-522
installed so they could talk to fighter escort.
According to oral histories, large bomber formations
did not "chit chat" on either HF or VHF once on a combat
mission- radio silence was required.  However, once the 
bombs were away, there was a lot of talk between the bombers
and between bombers and escorts.

> I've been lead to understand from people who were pilots or radio
> operators flying out of the UK that the VHF SCR-522 was "THE" command
> radio of choice by all concerned from early in the war ...
We must put these oral history stories in context.
Photographic evidence establishes the use of HF in small
aircraft in the ETO during WW-II.  However, most fighter
aircraft were outfitted with the SCR-522 and an LF range receiver
by late 1944 and early 1945.  I have two accounts from 
radio techs of the time, saying that they and their fellow 
techs hated the SCR-522.  They said they couldn't keep it 
on freq. because there was no effective temperature compensation.
Once the aircraft got at altitude, the frequencies shifted.

> I wonder if the SCR-522 was used as extensively in other 
> sub-theaters of
> the ETO, such as operations out of north Africa 
> against Italy and such.
I have no direct evidence one way or the other.

> Is it likely that "Pipsqueak" mode 
> might have been the main use of the SCR-274-N in the ETO,...
No chance.  Although it was obviously designed for
use with the 274N, very little has been found about the
SCR-274N being used with the Pipsqueak.
Such large scale use could not go unnoted.
Tons of docs say it was used for communication.
The Pipsqueak was designed for use with both SCR-274 and
with SCR-522.  It specifically selected a channel other
then the primary communication channel (channel 4 on the 522)
for DFing by ground stations.  Several sets in a formation 
keying at once would invalidate a DF fix, so it's 
reasonable that it was designed to be used by one aircraft
at a time.  

An interesting aside- I have a BC-608 in the sealed box.
It is marked "one each, UNIT-"  no other identifying 
markings other then the manufacturer's numbers.
Wonder what kind of skullduggery was going on there.

Please tell us more about the BC-615.  
I am unaware of this piece and would like to know more about it.

> Does anyone know if the USN had some 
> intended prototype of a receiver to
> pair with their ATC (AN/ART-13) transmitter that had comparable
> frequency coverage (200 - 1500 kcs, 2000 to 18100 kcs)?
The ATC/BC-348 are known as AN/ARC-8, and this match is 
documented in heavy Army bombers in November 1944 
(not under that nomenclature).
There is documentation to match ATC with ARC-5, RAX and ARB
in Navy installations.  I seem to remember a Navy aircraft 
photo with BC-348/ATC, but can't find it right now.

73 Dave S.