I think this may cause some interesting debate but I'm sure we can keep it polite :-)
I have just looked into the forum again, especially at the “winter flying” topic, which sort of amuses me… Since I have forgotten how to post replies directly, may I use this channel to make some comments?
This is the first time I hear that the “cowl flaps” on the Altenrhein-built Jungmanns are to generate a warmer front cockpit. I am a bit confused, to be honest. After several hundreds of hours of Jungmann-flying, I know for sure that my passengers in the front seat open them in summer, to get fresh air into the front cockpit when the heat from the engine really makes them feel too hot. They certainly keep them closed in winter. One of the photos I attach shows a winter operation (Locarno, Jan 20, 1969), where the crews have taped-over the flaps to eliminate as much cold air draft into the front cockpit as possible. Two of the attached photos show the original flaps on my A-15/HB-UUE. As is clearly visible, the openings are above of where engine heat can leave the engine cowlings. Remember, mine is an original Hirth HM-504-installation. The photo you have posted is of HB-UVC, which is a unique conversion with a Walter-Minor engine. Maybe it’s different with this one and the LOM-installations?
As to “winter flying”.: There is certainly nothing to worry about. Two photos attached I took on Dec. 30, 2006. the OAT on ground was
minus 2 deg. C. It’s just a matter of dressing up for the occasion.
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