wuzak
Captain
A series engines, as used in the XB-39, had the crankshafts rotating in the same direction, with a single output shaft with a gear driven by both crankshafts.
The B-series had opposite rotating crankshafts, and usually were fitted with remote gearboxes and extension shafts. Some of them were to use 90° drives, as was the case for the one to be used in the proposed McDonnell Type 1 - the engine being fuselage mounted and driving props on the wings via 90° gearboxes and extension shafts. At least one B series was proposed with an engine mounted reduction gear, driving contra rotating propellors.
The B-series had opposite rotating crankshafts, and usually were fitted with remote gearboxes and extension shafts. Some of them were to use 90° drives, as was the case for the one to be used in the proposed McDonnell Type 1 - the engine being fuselage mounted and driving props on the wings via 90° gearboxes and extension shafts. At least one B series was proposed with an engine mounted reduction gear, driving contra rotating propellors.
