Why did squadrons change their codes?

[Dave Homewood]

I have noted that a few RNZAF Squadrons seem to have changed their squadron codes (painted on the sides of their aircraft).

No. 75 (NZ) Squadron's aircraft were all orginally coded AA- but later in the war during the Lancaster period, apparently the squadron had three Flights, A and B retaining the AA- codes with C Flight coding its aircraft as JN-

And No. 6 Squadron's Catalinas were coded as XX- in 1943, but later in 1944 they seem to have changed to code letters KN-

I wondered in No. 75 Sqn's case if they had more than 26 aircraft, but that seems unusual as I believe the standard number was about 18 aircraft per squadron.

Does anyone know why these alterations were made?

[flyjoe180]

It appears that most RAF squadrons received new identification letters after the outbreak of hostilities in 1939, primarily to confuse enemy intelligence. (There is reference to this in 'Hurricane Squadron at War' (85 squadron RAF) by A J Brookes).

It seems some units received different codes as the war progressed, including for example 75 (NZ) Squadron:
Its code letters of "AA" became widely recognised on both sides, (when the unit operated as an oversize unit, some aircraft were coded "JN"). en.wikipedia.org/wiki/No._75_Squadron_RAF

And here www.rafweb.org/Sqn071-75.htm you can see 75 Squadron in fact had three codes, FO (Oct 38 to Sep 39), AA (Apr 40 to Oct 45), and JN (C Flight only, Feb 1943 - Oct 1945).

Very confusing all the same, it seems it was organisational and nothing more. I am unable to find any specific info on NZ codes and reasons for changes to unit coding.

[Dave Homewood]

Cheers Joe. Of course 75 Sqn wasn't our's when it was FO codes but still interesting to see the Sqn used that code.