It was to have a maximum speed of 600 km/h (370 mph) and be able to carry a bomb load of 4,000 kg (8,820 lb) to any part of Britain from bases in France or Norway.

An interesting feature was the inclusion of the Multhopp-Klappe, an ingenious form of combined landing flap and dive brake, which was developed by Hans Multhopp.

The Fw 191 followed established Luftwaffe practice in concentrating the crew in the nose compartment, also including the nearly ubiquitous Bola, inverted-casemate undernose gondola for defensive weapons mounts first used on the Junkers Ju 88A before the war, and in the use of a "stepless cockpit", having no separate windscreen for the pilot, as the later -P and -H versions of the Heinkel He 111 already did.

[citation needed] This also had the detrimental effect of adding even more weight to the overburdened airframe, plus there was also the danger of a single enemy bullet putting every system out of action if the generator was hit.

Ing Melhorn took the Fw 191 V1 on its maiden flight early in 1942, with immediate problems arising from the lower rated engines not providing enough power, as was anticipated.

Another problem arose with the RLM's insistence that all systems that would normally be hydraulic or mechanically activated should be operated by electric motors.

At this point, the RLM allowed the redesign and removal of the electric motors (to be replaced by the standard hydraulics), so the Fw 191 V3, V4 and V5 were abandoned.

The Fw 191 V6 was then modified to the new design, and also a pair of specially prepared Jumo 222 engines were fitted that developed 2,200 PS (2,170 hp, 1,618 kW) for takeoff.

Their lower power-to-weight ratio (each "power system" weighed 1.5 tonnes) meant that the armament and payload would have to be reduced.

Also, the cabin would be unpressurized and the guns manually operated, with a rear step in the bottom of the deepened fuselage — in the manner of the near-ubiquitous Bola gondola used by the majority of German bombers for ventral defense under the nose — being provided for the gunner.

Although the Fw 191 will be remembered as a failure, the airframe and design eventually proved themselves to be sound; only the underpowered engines and insistence on electric motors to operate all the systems doomed the aircraft.