Pogo wrote:
... a '109 or Buchon (did I get that right?) ...
Pretty right. Should have an accent over the 'o': Buchón. Strictly the name (the colloquial, local name for a kind of Spanish deep chested pigeon*) is a nickname, rather than the type's official name - Hispano HA-1112-M1L. Mostly you'll see Buchon without the accent though.
This is the man who rang up the Spanish embassy to try and settle an argument over how Buchón was pronounced...
*Not a pelican, despite some refs that confuse a unit insignia, also based on the Buchón's deep nose profile, with the name.
Pogo wrote:
JDK wrote:
And a nit pick, it's Bf not BF.
This is actually one of the major points I was after, to wit, how to type 'er in correctly. I recently became somewhat intimately involved in German WWI aircraft, and am still only about 97.953% confident that 'D.VII' and 'Dr.I' are correct.....
My gut instinct always said that it was an indicator of sorts; that ME-109 came from those who knew little about this stuff, Me 109 from those who know a bit more, and Bf 109 revealed the specimen as a fellow OCD case.
Sounds about right! I can excuse the OCD as, being an editor, it's part of the
job.
However, it depends on the source. Wartime Allied accounts didn't differentiate too much and they were often known as 'Em Ees' or 'Messers' etc, so if you are reporting a veteran's account, that's what
they may've said. Sometimes they were even He 113's, although it's funny how those combat claims seem to have been 'corrected' since!
Pogo wrote:
Back to the split flaps, understand they're equivalent to cowl flaps and/or shutters for radiators, oil coolers, etc., and were not on earlier models. Dang, am I getting smart or what?

OK, Equivalent, yes, the but
all Messerscmitt 109 variants had variable flaps on the rear of the radiators, from the first models to the last. However, up to the E model there was only a lower flap, with the radiator and it's smaller fairing set further (in effect) forward and the inner section of the wing was just the inner end of a long, standard flap.
Think of the exit-air flap door on the P-51 for an equivalent, except two, moved to the wing. The Spitfire and Hurricane also has a similar set up.
(The shapes of the radiator intake and exhaust were quite a new understanding of an aspect of the venturi and Meredith effect in the 1930s, so the shaping of the intake and exit were carefully worked out, and the way of varying the radiator's efficiency on aircraft's speed and engine heat was a simple flap at the rear, changing the size of that exit vent.
Some discussion of how to get thrust, rather than drag, using hot air from your shaped rad ducting, here:
viewtopic.php?f=3&t=33360&p=333399 )
From the F onwards, the radiators were wider and the radiator housing extended to the trailing edge. The wing upper surface gained a separate part of the flap, which could be 'raised' as well as lowered with the rest of the flap, rather than being part of the whole flap. So then the lower flap could be
lowered to increase the air exit area and the upper flap could be
raised to also increase the air exit area. I'm sure Lynn's account of their actuation difference is correct - I don't know that bit. What's interesting is when they put the Merlin into the 109G airframe, they kept the G type radiators and added another rad under the nose, as well as the nose oil cooler that'd been there all along. When a certain Buchon was converted for a certain collection into a 109E by hanging the 109E-type engine on it, it still had the G style rads giving Buchon-nuts like me a moment of nit-pickery delight.
Um, I hope that helps? That's about the 12th re-write with corrections. Much easier to describe on a walk around...
Cheers,