Engineer Ermolaev participated in the design and construction of a record aircraft Stal-7 “. Leading team of designers, after the arrest Bartini, Ermolaev used the experience gained in the development of night-bomber and its applications in series production.
In the summer of 1940 with one of the airfields up a new bomber, designed team, led by Ermolaev. The plane, originally received the name of the DB-240, then – Ep-2, was a direct development of the aircraft “Steel-7″. The scheme of the first prototype of the DB-240 differed from the “Steel-7″ new nasal glass cockpits, mate, single cockpit, shifted to the left side, rear gunner mount, separated tail and bombootsekom in the fuselage. Chassis, power group, and several other elements were left unchanged. The plane was a four. Instead, a mixed design “Steel-7″ was adopted entirely new, based on the use of lofting-template method of production of aircraft and related technologies. The fuselage length of 16.34 m – polumonokok stringer-type layout bomber and a large bomb bay. Thanks to the narrowing of the wing (4,8), while lengthening the 7,3, and therefore at high root chord distance between the spars on the axis of the aircraft has reached 2,5 m. The transformation of the construction wing of the replacement of pipes on profiles is not justified, and spars in the series remained the same – welded tube. Engines were assumed to be M-106, but they were late and had to put the less powerful M-105. Small arms have been weak – two machine guns and one SHKAS UBT. On the inside of the suspension could be placed up to 1000 kg bombs.
Performance of DB-240 were found to differ. No comments were few customers and the fall of 1940 the aircraft was put into serial production. During the series built aircraft modified in accordance with the experience of fighting. There were changes in engines, weapons, aircraft size, but its characteristic feature – a wing-type “reverse gull” area of 72 m2 – persisted.
Until the fall of 1942 the factory built 128 aircraft Ep-2 twin-engined F-105 1050 hp Then, to increase the range of flight engineers redesigned the plane for diesel engines ACh-30B by 1250 … 1500 hp, with them were released almost 300 bombers. Aircraft Er-2 of the last series were accelerating at a height of 6 thousand meters to 420 kilometers per hour. Their ceiling is reached 7700 m, range from 1 ton of bombs – 5 thousand km. Take-off weight ranged from 13,300 kg to 18,580 kg in the transshipment option.
Er-2 have been successfully used for attacks on enemy military installations located in its hinterland, including in the capital of Nazi Germany.
Performance characteristics
Year adopting
Wing span, m   23., 00
Length, m  16.40
Wing area, m   272.10
Empty / takeoff, kg   6500/12570
Engines   Two M-105 (1100 hp)
Maximum speed, km / h   500
Cruising speed, km / h   437
Range, km   4100
Maximum rate of climb, m / min   990
Practical ceiling, m   7700
Crew   4
Bomb load, kg  1000
Armament 1940   20-mm SHVAK, 12,7 mm UBT and 7,62 mm SHKAS