I have about 120 hours in the last four years, primarily in the CAF MN Wing BT, and a few in another BT-13.
I echo the other comments regarding flap deflection and fuel tank leaks. We limit flap deflection to 30 deg for that same reason. And as already mentioned, there is very little reduction in stall speed from 30 deg flaps to 60 deg flaps. One version of the pilots flight operating instructions states 30 deg flap stall speed as 65 mph and 60 deg flap stall speed as 62 mph. Another version of the operating instructions states 65 mph for both flap deflections. I'd imagine there is considerable drag difference between the two settings.
One question I'd ask is, does the BT you're referring to have a constant speed prop installed? Or the original two position style? The MN Wing BT has a constant speed prop on it along with a manifold pressure gauge installed. The original two position prop and instrument configuration did not include a manifold pressure gauge. On the constant speed prop installation, it is possible to overboost the engine. The FAA Type Certificate Data Sheet issued after the war includes a manifold pressure limit of 36.5 in Hg.
The other BT I have flown has the original two position prop and no manifold pressure gauge. My limited experience in that aircraft was that the throttle is just to be "firewalled" on takeoff. The takeoff roll and initial climb at that setting were noticeably shorter, which leads me to believe it was running at a manifold pressure much higher than 36.5. I have subsequently not been advancing fully until I get a bit more time/feedback as to proper operation.
I see no reason to identify the two position prop as causing any issues a constant speed prop installation wouldn't have also caused (i.e forgetting to set proper position). The same is true for either of those configurations.
Of course, it is a tailwheel airplane, and should be flown with the same care as any tailwheel, however, the wide main landing gear stance results in fairly forgiving handling qualities (for a tailwheel).
Tailwheel shimmy seems to be a relatively "common" issue to deal with. The service instructions do cover this. If you run into problems with that, PM me and I will share details regarding MX items to review.
Overall it's a great airplane to fly and has great flying qualities. One other item, there are two different aileron servo tab gain settings which result in noticeable difference in roll control forces. I prefer the configuration with less servo tab gain. I have not found any document describing the different tab gain options, or what scenario it was added for. Might have just been a requested change not found in currently available documentation. I'll dig up some photos of the different servo tab attach point options.
Jordan
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