[ARC5] CW Use in Fighters

[Robert Eleazer]

One thing I have wondered about for some time is the use of CW for communications in single seat fighter aircraft. The SCR-274-N had the capability and I even recall seeing a aircraft radio control box with a built in CW key in an old issue of the Fair Radio Catalog, but did they actually ever plan to use that mode?

I recently looked in the P-40D/E pilot's manual, and sure enough, there are instructions for using the SCR-274-N in CW mode, and it also says that CW gives the greatest effective range as compared to voice. The mike switch is used as the CW key. And interestingly enough they explain that in CW or Tone modes the transmitter dynamotor keeps running continuously whereas in Voice mode it only spins up when the mike key is pressed, so they do not recommend leaving the transmitter in CW or Tone mode. 

But for the SCR-283 installation for the P-40D they point out that the receiver lacks a BFO so CW is not available. So if the earlier radios lacked the capability, why were pilots schooled in Morse Code?

Well, of course beacons use modulated code signals for ID and Morse is needed for that purpose. And I found a description by a pilot flying the airway light beacons at night in WWII. Each beacon had a light on top that signaled its identifier in Morse.

But I have yet to find any written down historical cases in which pilots in single seat fighters used CW for two way communications.

Wayne

WB5WSV