Warbird Information Exchange

I am not that sharp on aircraft ID but that #231 sure looks like it has a Wright R975 (BT-15). I'm not that familiar with Pratts so could( and likely) be completely wrong.

Only the straight BT-13's had the main landing gear fairings. They were discontinued on the A'a. B's, SNV's, and -15's. This is from the illustrated parts manual.

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If God had wanted man to fly behind a flat motor, Pratt Whitney would've built one.

That's correct. Those be Pratts. The fairing around the base of the pitot tube was later discontinued also.

Are you sure thoise are BT-13's? They got covers over the legs.

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They're straight BT-13's (as opposed to fairingless BT-13A's, B's, SNV-1's, -2's, or BT-15's.)

Going from memory it's like this:

- the Vultee model 54 is a BT-13
- a model 63 is a BT-13A or SNV-1 (same as BT-13 but no fairings)
- a model 74 a BT-13B or SNV-2 (same as BT-13A but 24 volt instead of 12 and different wingtips)
- a model 79 a BT-15 (Wright R-975 powered).

Still haven't quite figured out how to differentiate which models had wooden components, but basically that's it. The airplanes in those pics are all Model 54's, or BT-13s. Don't know whose field codes those are but somebody like Jack Cook can probably tell us.

Dan

Thanks for the Trainer 101 lecture, gentlemen. I have always been confused about which was a 13, which a 15 etc., and how to tell the difference. With the photos and Dan's explanation, it becomes clear(er)

Doug

I have a BT-15 Question, When I was at Airventure we where looking at a Wright powered plane and the ring cowling did not have the cut out for the propellers two position controls. How is the pitch changed on the Wright powered engines and are they two position or constant speed props?

Steve

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A Wright R975 can run a governor in 2 locations. Either with a nose case mounted governor (comes out at the 2 O'clock position looking aft) or they can be mounted in the back off the accessory case with a 3 way drive below the right mag. If the governor is mounted off 3 way in back then a line is plumbed up to nose case where the old 2 speed valve used to reside. If there is no governor fore or aft then it will have to run a 2 speed valve on the nose case at the same position where a nose case gov would be and you will see an auxilliary feed line entering the valve off to the port side of case. (this was a service bulletin add on to help shift sluggish props....still barely adequate!)

Thanks for the images!

BTW the Hangar and the buildings behind look EXACTLY like the buildings at Sequoia Field about 12 miles North of Visalia. We have been led to believe that Sequoia is the only remaining WWII training base in the US that still has all of its original buildings still standing. corrections Please!

Also, Sequoia field used PT-22's for most of its service life and later PT-17's. when we inspected the North hangar for possible use, we found several examples of the original painted signs intact and the flight assingment chalk board. At one time the field had a large rectangle for six paralell runways. Walking the oiled surface will dislodge quite a number of Kinner carburator/exhaust parts driven into the sticky muck.

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Charles Neely