[ARC5] 1155

[Mike Morrow]

I wrote:

> ...the UK helped get the USA away from attraction to its marginally effective
> MF/HF command sets to VHF.

Geoff wrote:

> I think not as VHF has severe distance limits that only HF could cover.
> Both had their purpose and were widely used with excellent results by US
> forces.

What we've got here is...failure to communicate.

My statement above clearly indicates its application to *COMMAND* sets,
not liaison sets.

Command sets are used for plane-to-plane communication in formation,
and for short range communication to air fields on departure and
approach.

With respect to those "severe distance limits", the operating instructions
for many US VHF sets contain a graph of line-of-sight-to-ground range
at VHF frequencies.  The one in the 1944 AN/ARC-1 manual indicates the
range to be greater than 200 miles for an aircraft at 30000 feet.
Many of us have used two-meter FM HTs to talk with someone flying
at 30000 feet several states away.  It's not theory...it's real.

The command set function has always been better served by VHF (or UHF)
equipment.  No one has ever cited a credible condition where, if
VHF sets *had* been available, they would not have better served the
command set function than MF/HF sets.  The UK helped to bring
the US forces into that realization.  I challenge anyone to find a
pilot's memoir that bemoans the replacement of the SCR-274-N gear
with the SCR-522-A.  Pilot praise for the SCR-522-A and the later
AN/ARC-3, expressed as great preference for the "push button" rather
than the "coffee grinder" command sets, can be found with little
difficulty.

> I also understand that the UK outfitted some of their aircraft with 
> better performing US HF gear so they wouldnt get lost on long flights.

That equipment was definitely not a MF/HF command set.  It was AN/ARC-8
(AN/ART-13A and AN/ARR-11) *LIAISON* equipment.  (AN/ARR-11 is the JAN
name for the BC-348-*.)

Mike / KK5F