- Long-range bomber
- First flight: 1943
Beginning of the war prevented restart of mass production of the Er-2 with M-40F diesel engines as it was planned in 1941. Rapid German advance to Moscow made it necessary to evacuate the experimental factory and the V.Ermolayev Design Bureau to Kazan, where it was impossible to resume works on improvements of the bomber. Having returned to Moscow in Summer 1942 the Bureau found itself without working accommodation, since all its working spaces had been given to the S.llyushin Design Bureau. It took another year to develop a new variant of the Er-2, this time with M-30B diesels.
At the beginning of 40-s 1250 H 1500 hp aircraft diesels were considered one of the main achievements of the Soviet engine industry. These economical engines, fueled by easily available tractor kerosene made possible combat range, tremendous for that time. For the Er-2 it was 5500 — 6000 km with 1000 kg of bombs to be dropped at the middle of the route. Moreover, aircraft with diesel engines definitely were not so flammable. But diesels had a weak side — big weight and insufficient reliability.
At the end of 1943 having passed state trials the Er-2 with M-30B diesel engines (soon the designation of the engine changed to ACh-30B, after its designer A.Charomsky) was put into production at an aircraft factory in Irkutsk, and at the Spring of 1944 began forming of units, equipped with the newest bomber. By mid-Summer of 1944 the Long Range Aviation (Soviet equivalent of Strategic Bomber Command) had seven regiments, flying on Er-2s. But these regiments were mostly on paper, since by the end of the year no more then forty planes had been produced and delivered to the operating units. The main reason for such a delay being exceptionally low reliability of the engine (its fuel system, for instance).
Only in April 1945 two regiments of the 18th Guards Division became operational and took part in fighting. At the closing stage of the war Er-2s bombed Konigsberg and Berlin suburbs. However, the diesel Er-2 saw limited combat — the general situation was so unfavorable for Germany that there were no need in mass night bombing raids against its rear targets.
During Summer of 1945 in the 18th Guards Division were held operational trials of the Er-2 with ACh-30B diesels, ended with negative results. After the war quality standards for military equipment became much higher, and many defects that were turned blind eye on before by military representatives and air crews were no more tolerated. The Design Bureau that after the death of V.Ermolayev was headed by a renowned designer RSukhoy was tasked with elimination of all defects, including power-plant problems, in extremely short period — till 1 January, 1946. Unfortunately, it was not done, moreover, new aircraft industry leaders had different views on diesel-powered planes. It was the start of the era of jet propulsion, and diesels that once looked so promising were loosing their appeal quickly.
In Spring of 1946 it was decided to withdraw the Er-2 from service with the Red Army Air Force units. Actually, its production had been terminated even earlier, in August, 1945. In all, 360 planes were produced.