Reichsluftfahrtministerium (RLM). This specification, first proposed by the RLM on 3 June 1936 – ironically, the same day that the main advocate for the Luftwaffe having a strategic bomber force, General Walther Wever, lost his life – called for an aircraft more advanced than the Dornier Do 19 or Junkers Ju 89 "Ural bomber" prototypes that General Wever had championed. The Bomber A aircraft specification required the plane to carry a bomb-load of at least 1,000 kg (2,200 lb) over a range of 5,000 km (3,100 mi), with a maximum speed of not less than 500 km/h (311 mph) at altitude.
This was a formidable specification, calling as it did for an aircraft able to outrun any modern fighter – as was expected with the top speeds of the main force Schnellbomber concept – and outperform, by a considerable margin, any bomber then in service. On 2 June 1937, Heinkel Flugzeugwerke received instructions to proceed with construction of a full-scale mock-up of its Projekt 1041 Bomber A. That was completed in November 1937, and on 5 November 1937 it was allocated the official RLM airframe type number "8-177", the same day that the Luftwaffe High Command (OKL) stipulated that the new design should possess sufficient structural strength to enable it to undertake medium-degree diving attacks. Heinkel Flugzeugwerke's estimated performance figures for Projekt 1041 included a top speed of 550 km/h (342 mph) at 5,500 m (18,050 ft) and a loaded weight of 27,000 kg (59,500 lb). In order to achieve these estimates, Heinkel's chief designer, Siegfried Günter, employed several revolutionary features.