1939–1945: World War II

With German rearmament in the 1930s, the company again began producing aircraft engines for the Luftwaffe. In 1939, BMW bought Brandenburgische Motorenwerke, also known as Bramo, from the Siemens group of companies and merged it with its aircraft engine division under the name BMW Flugmotorenbau GmbH. A new factory at Allach, outside Munich, began production of aircraft engines later that year. Over 30,000 aero engines were manufactured through 1945, as well as over 500 jet engines such as the BMW 003. To enable this massive production effort, forced labor was utilized, consisting primarily of prisoners from concentration camps such as Dachau. By the end of the war, almost 50% of the 50,000-person workforce at BMW AG consisted of prisoners from concentration camps.

Among its successful World War II engine designs were the BMW 132 and BMW 801 air-cooled radial engines, and the pioneering BMW 003 axial-flow turbojet. Towards the end of the Third Reich, BMW developed some military aircraft projects for the Luftwaffe— the Strahlbomber, Schnellbomber and Strahljäger— but none of them reached production.