[ARC5] History and Context of the ARC-5 sets

[Leslie Smith]

Hello ARC-5 Group,

We have a general picture of the origins and history of the ARC-5 sets, beginning with loss or airmen when FDR instructed the US Air Force to take over the postal service and so on.  Then we know that FDR instigated a program to build 50,000 fighter aircraft, and a contract for some 28000 ARC-5 sets was awarded in June 1940.  Gordan White wrote a series of instructive articles on this subject, and he is my main source of knowlege.  But I find there are many gaps in my knowledge.

The first one begins with early navigation history.  What methods were used in the mid 30's for air navigation?  Was it all map-work and visual sighing, or did radio have a role?  Was the ARC-5 system the first, and if so what was the set-up?  I assume that the R-23 "navigation" sets had some role, and I have seen photos of circular "loop" antennae from PBY aircraft (or so it was said about the photos I saw).  How did this system work?  How was it used in and after the war?  

When I listen on the frequencies below 520kHz I hear many "nav" beacons here in Australia.  One night I filled up a full sheet of paper listening to the MCW callsigns.  "SGT" - that must be Singleton army base.  "CH" - that must be Coffs Harbour.  The band was full of these beacons.  So how are they used, and (now) by whom?  What will the GPS system do to them?

I have other gaps in my understanding of this too.  How did the VHF system come to be adopted, and why was Drake so much against VHF systems?  How and why did the Brits adopt the VHF AM air band, and how and when was the system introduced in other countries?  I'm certain the Brits didn't go across to Berlin and say to Hitler:  "Now while this war or yours has been going on we have found that the VHF band around 120MHz works really well for our aircraft.  Would you like to join us in a convention to use this frequency for airports in general, and the Luftwaffe in particular?" 

What happened at Midway (I mean regarding air to air communication, not the battle).  I have seen references to problems with communication in the battle of the Coral Sea, and a hint that the problem was mentioned in despatches by the TF commander in a report dated May 8 1942.  What happened here?  How long did it take to develop the VHF system?  Was the VHF air-band a civilian system first, (eg in Britain before the war) or only after the military had developed it in the war?

In other words, I'm interested in more detail about not only the ARC-5 sets, but the CONTEXT in which the ARC-5 sets developed and operated.  There are other mysteries too.  

All contributions read with great interest!


Les Smith
formerly VK2BCU
Australia 

-- 
_______________________________________________
Surf the Web in a faster, safer and easier way:
Download Opera 9 at http://www.opera.com