Originally Ha 141, designed by Dr. Ing Vogt in 1937 as a private venture, the prototype first flew on 25 February 1938. The A series flew well, but the five BV 141B-0’s were plagued with various troubles. The B series first flew on 9 January 1941. These problems were solved with the development of the Argus As 820 power plant giving a maximum speed of 345mph, a vast improvement on the previous BMW engine. Although originally designed for a reconnaissance role, it was transformed into a torpedo carrying Maritime Patrol aircraft designated Bv 141B-05 and assigned to Küstenfliegergruppe 906.