B-25C/D Exhaust Stub Question

RHIP

Crimea_River said:

Yep, old thread I know but I'm toying with restarting my B-25 conversion.

QUESTION: As I would like to pose the cowl flaps in a semi-open position, I'd like to know if the staggered configuration seen in the LIFE magazine shots and in the manual excerpt, Fig 215 all in post #2 represent a "natural" flap position. Note how the flaps over the exhaust stubs appear to be opened further than those higher up the cowl.

Click to expand...

Hi Andy!
I'm far from home and don't have many sources available, but I know exactly what you mean and IMHO I know the answer.
First of all cowl flaps have to be open during take-off. So if you want to represent this situation, the lower flaps should be more open than the top ones. Many photos in this thread (above) show this exact position of the flaps. You've seen this on the LIFE-photos with the Dutch Mitchells. Same with some of the other photos of late cowlings (with the S-stacks).
One further explanation though: the "finger stacks" were an interim solution to substitute the large single exhaust pipe, glowing red in the clear African night sky. The cowl and the cowl flaps were NOT redesigned at that point. An early B-25B or C/D would have the same flaps as "Dirty Gertie" e.g. Even when the S-stacks became the final design, the cowl flaps worked in the very same way.
Check the docu "How to fly the B-25" here:

View: https://www.youtube.com/watch?v=-YQmkjpP6q8What you need is @7:06.
Cheers!

Thanks CATCH 22 Yves. Hope you are doing well.The project has gone back in the box as I still have not come up with a way to make the finger stacks but hope that some day I will be able to finish this.