|
|
The Consolidated XPT-5 was a version of the PT-3 that used a Curtiss Challenger engine.
The XPT-5 was produced by converting the XPT-3. This was the original prototype for the PT-3 and had originally been completed as a PT-1, but had later been given new wing panels, a revised vertical fin and a Wright J-5 air cooled radial engine.
The XPT-5 was powered by a 186-hp Curtiss Challenger R-600-1 two-row six-cylinder radial engine. This would have given it about the same power as the production aircraft - the original Wright E of the PT-1 provided 180hp and the J-5 Whirlwind (R-790) of the PT-3 provided 220hp.
The Challenger was an unusual engine, with two staggered rows of three cylinders (with the cylinders in the second row in the gaps between the cylinders in the first row, so from the front it looked like a standard six cylinder row). It was economical to run, but didn't run as smoothly as had been hoped. Although it was installed in a number of commercial designs, in particular from Curtiss, it was often replaced because the two row layout caused too much vibration.
The XPT-5 was soon converted to the PT-3 standard by giving it the normal Wright J-5 engine.