When it became apparent that the Taurus engines had problems, planning commenced to re-engine the aircraft with Pratt & Whitney R-1830 Twin-Wasp radials, which were of similar diameter and slightly lighter, driving Hamilton Standard bracket-type variable-pitch propellers. There was no guaranteed supply of the Twin Wasp and production reverted to the Taurus-engined Mark Is after 165 Beaufort Mark IIs had been built, starting with "AW244", which first flew in September 1941. Performance with the Twin-Wasps was marginally improved: maximum speed went up from and the service ceiling increased from . Normal range was reduced from .