[MRCA] Vintage radios in Historic Aircraft

[MARK DORNEY]

There has been some discussion of the use of vintage radios in historic military aircraft.  There are some basic things to be taken into consideration when doing this. :

1) Modern aviation communicates in the VHF frequency range. MOST military aircraft radios in use prior to 1945 operated in the MF and HF frequency range - and won’t be of much use for aviation communication. The FAA requires VHF transceivers. 

2). Most historic aircraft are simply not that big. Vintage aircraft radios and their associated accessories tend to be bigger and much heavier than modern radios. It really only makes sense to install vintage radios in operational larger fighter, bomber and transport aircraft where limited tours of the inside of the aircraft can be offered to the public ( of course, for a small fee ). It makes NO sense to put vintage radios in a small, single seat aircraft where the radio is mounted hidden in the fuselage, where nobody will ever see it. And maintenance is hard enough to do on these radios, both physically and logistically. It becomes more of a pain in the butt if you have to jerk around in the confined space of the fuselage of, say, something like a P-51 Mustang. 

3)  The few common military VHF sets I’ve some across are very limited in how many frequencies they can actually operate on. For instance, the T-23/ARC-5 is crystal controlled, and can operate on 1 of  4 preset frequencies. And that frequency is set pre-flight, and cannot be normally changed in flight.  The AN/ARC-1 has 10 crystal controlled frequencies it can operate on, and there is a remote that does allow for a frequency change to 1 of the 10 frequencies of the crystals installed in the set, in flight. Other aircraft VHF sets of the pre-1945 era operate in a similar fashion. VFO’s of the time period were prone to float, and certainly a pilot of a single seat fighter had neither the time nor the room to be constantly screwing around with a radio while flying their aircraft. 

4) Some ATC equipment will only be of any use as a decoration in the aircraft. For instance, WW2 transponders were what is now referred to as a Type 1 transponder. When triggered by a specific radio signal, they tell an ATC operator who you are and where you are.  Modern aviation requires an aircraft to use a Type 3 transponder. A type 3  transponder tells an ATC operator who you are, where you are, what altitude you’re flying at and what heading you’re on. Another instance of equipment with only a decorative use is in C-47A. That aircraft had a navigation system called the “GEE”.  Similar to LORAN-A, it went out of use in 1960. So restoring a GEE receiver to operational use is really just a labor of love, since you’d only be able to listen to a whole lot of nothing on the set. In these two instances, a mock up or using the equipment shell to hide modem equipment might be a better, cheaper and more practical solution ( Camouflage is more than just painting  something green). The beacon radios on the ARC-5 and SCR-274-N are also of limited use, since a lot, but not all, of the radio navigational beacons have gone out of use.  The exception would be the broadcast band receivers. If the radio tower transmitting the signal of a commercial AM station antenna is at a known, fixed location, using a directional antenna would allow for an aircraft to home in on that signal ( ie, like in the movie “Tora,Tora,Tora!” ). Of course, a modern GPS system is so much smaller and easier to use. VOR was in extremely limited use in 1944 -45, but certainly was not common until after WW2. TACAN came in post WW2. 

73
Mark D. 
WW2RDO



“In matters of style, float with the current. In matters of Principle, stand like a rock. “.   -   Thomas Jefferson 

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