Hi Udet,
>you are right hohun, some sources call it friederich but some call it franz.
The problem is, all sources calling is "Franz" are pretty recent. I doubt you'll find any mention of a "Franz" in a book that's much older than, say, 1990. In fact, I saw it for the first time in about 1995 when I checked the Air Warrior plane files (which were poorly researched in some points at least).
"Friedrich" in WW2 was the official phonetic code for "F", and the Luftwaffe crews absolutely adhered to this pattern. This phonetic code goes back to the early days of telephone communication and actually was used by everyone on a regular basis - not just the military, like it seems to be the case with the US phonetic codes. In fact, civilians still routinely use the code in Germany (and Austria) even today.
In short, there's no chance of any German soldier not being familiar with the phonetics and messing it up badly enough for the name to stick. For a foreign author, however, it's easy to confuse "Fritz" - which is the abbreviated form of "Friedrich", though it's never used like that when phonetics count - and "Franz" and to accidentally create a myth that way by getting it into print somehow.
I'd like to invite everyone to try and find an actual German quote from WW2 that uses the name "Franz" for the Me 109F - I've never seen anything like that, and I'm absolutely convinced that you won't be able to find such a quote either.
It really would be the same as referring to the F-18F not as "Foxtrot", but as "Farmhand" - it would make no recogizable sense at all and deviate from all established patterns.
You're right that the "Franz" designation has gained quite some popularity, but I hope I've managed to provide some reasons to consider "Friedrich" the more authentic of the two names at least.
In my opinion, it's the only authentic one, but I'm sure you already guessed that ;-)
Regards,
Henning (HoHun)