|Weights (kg) and Loads|
|Wing Load (kg/m2)||147|
|Power load (kg/hp)||3.4|
|at 0m||365 (382 S/S)|
|at 2500m||396 (421 S/S)|
This development was initiated after fall of Smolensk to Germans on 16 July 1941 placed Moscow in imminent danger and forced evacuation of Mikulin engine works (producing AM-38 engine) to a location behind the Ural mountains. There was a clear risk of shortages with this engine until production re-started at new location.
M-82 engine mounting was unarmored (due to better survivability of air-cooling engines) and mounted lower to retain aircraft thrust line and minimize pilot view restrictions. As a result, aircraft had a distinctive humped nose appearance. Armored gunner position with 12.7mm UBT machine gun was surrounded with a glazed covering. More conical spinner with new propeller were fitted, fuel tank capacity was increased to 724 litres. Aircraft was ready in September 1941, and was presented on State Acceptance trials in February 1942.
Performance of Il-4 were found slightly inferior to Il-2, but at the moment of decision making it became clear that there will be no shortages with AM-38 engine. Plus the M-82 had its optimal performance at altitudes well above those needed for the Stormovik. Project was cancelled and designation Il-4 was allocated to DB-3F long-range bomber;