Aircraft construction department of GWF reopened 2 October 1933, with design bureau under Dipl.-Ing. Albert Kalkert. Built Ar 66, He 45 and He 46 whilst designing Go 145 biplane trainer (9,929 by GWF and Ago, BFW and Focke-Wulf). Kalkert also designed Go 146 light twin, Go 147 tailless air observation post, Go 149 aerobatic trainer and Go 150 light twin. GWF also assisted design of DFS 230 and managed production and was by far chief source of Bf 110 twin-engined fighter (over 3,000). Go 242 assault glider (GWF built 900 of 1,528 total) was fitted with twin GR14M engines to become Go 244 (133, all conversions). Horten Ho IX twin-jet flying wing fighter was built as Go 229, Go 345 assault glider remained prototype, but 12 pre-production Go-Kalkert Ka 430 gliders were completed.