Following the debut of what would become the Luftwaffe's primary "seaborne" maritime patrol aircraft, the rival trimotored BV 138C flying boat in March 1941; from mid-1941, Condor crews were instructed to stop attacking shipping and avoid all combat in order to preserve numbers. In August, the first Fw 200 was shot down by a CAM ship-launched Hawker Hurricane, and the arrival of the U.S.-built Grumman Martlet, operating from the Royal Navy's new escort carriers, posed a serious threat. On 14 August 1942, an Fw 200C-3 was the first German aircraft to be destroyed by USAAF pilots, after it was attacked by a P-40C and a P-38F over Iceland.