Bomber B - The Bomber B Project

The Bomber B Project

Junkers had been studying dramatically more capable versions of the Ju 88 powered by their relatively compact Jumo 222, or the four-crankshaft Jumo 223 diesel aviation engine design from late 1937. No serious work was undertaken, but after Heinrich Hertel left Heinkel and joined Junkers in 1939, the EF 74 design was submitted to the RLM in May 1939. Accordingly the RLM sent out the specifications for Bomber B in July 1939, the Ju 88 retroactively becoming Bomber A, which was also an RLM designation initially used on June 3, 1936 for a heavy bomber concept, starting the Heinkel aircraft project that would eventually become the Heinkel He 177. Bomber B called for a new medium bomber with a maximum speed of 600 km/h (375 mph), able to carry a bomb load of 4000 kg (8,820 lb) to any part of Britain from bases in France or Norway. To improve crew performance and defensive firepower, the designs were to have a pressurized cabin with remotely aimed armament. With the extended range, larger payload and better performance, the Bomber B design would replace all existing bombers in service.

Arado, Dornier, Focke-Wulf and Junkers all responded with designs, and Henschel later added its own entry (the Hs 130). However, it was clear even at this point that the call for designs was to some extent a formality, as the Junkers design had already been selected for production. The Ar 340 was dropped in the design stage and Do 317 was relegated to low-priority development, while prototype orders were placed for the Fw 191 and the Ju 288. With the Focke-Wulf and Dornier projects as first and second backups, the Technisches-Amt technical development office of the RLM started using these other designs as experimental testbeds. For instance, as the aircraft would be operating at high altitudes, they suggested that all hydraulic systems on the Fw 191 be replaced with electrical ones instead to avoid the possibility of freezing up, something that had already been largely implemented from the beginning, as the Fw 191 bore the nickname of Das Fliegende Kraftwerk (the flying power station). However this dramatically increased the complexity of wiring the planes, and the chance that one of the many motors would fail was considerable. But that was not terribly important—it was felt that the Junkers design would work anyway.