Ilyushin Il-2 Shturmovik (1941): the armoured bath

1941·410 km/h·36,183·Mikulin AM-38F V-12, 1,720 hp·5–12 mm, ~700 kg·765 km

· THE STORY

A bath of steel with wings

The Il-2 went into action in the first weeks after Germany invaded the Soviet Union in June 1941, and the Red Army never had enough of them. It was built around a bath of armour plate that carried the engine, the fuel, the radiators and the pilot inside it, and it flew at tree-top height straight into the flak, firing cannon and rockets and dropping bombs on tanks. Stalin told the factories it was as necessary to the army as bread. More than 36,000 were built, and around 10,000 were lost — it was hard to kill, not impossible.

410 km/hTop speed36,183Built

· WHY IT MATTERED

Armour as structure

Most aircraft bolt armour plate onto a light frame. The Il-2’s forward fuselage was the armour: a welded shell of 5–12 mm steel weighing about 700 kg — roughly a seventh of the aircraft — that was the structure. A 20 mm hit that would have finished a fighter often did nothing. The gunner, added back in 1942 after single-seaters were slaughtered from behind, sat outside the bath and suffered about four times the pilot’s casualty rate.

GO DEEPERThe armoured bath →

· WHY IT MATTERED

The tank-killing carpet

At Kursk in 1943 the Il-2 opened four containers under its wings and let go of 192 small shaped-charge bombs, each 2.5 kg, that fell in a strip a few hundred metres long. No aiming was needed: any tank inside the strip took several hits, and a shaped charge that small could still burn through a Panzer’s engine deck.

· WHY IT MATTERED

Built for one height

Everything about the Il-2 was tuned to the fifty metres above the battlefield. Its engine was geared for low altitude, its guns were for soft vehicles and its armour faced the ground. Its service ceiling of 4,500 m would have been useless in the West; in the East nobody needed it.

· THE ENGINE

The biggest V-12 of the ten, geared for tree-top height

The AM-38 was a fighter engine, the AM-35, deliberately made worse at altitude: its supercharger was geared down so that all of its air went in at low level, and its compression ratio was dropped to six to one so that it would run on whatever fuel the front had. At 46.7 litres it was the largest engine in this list, heavy and cheap, with a ten-minute emergency rating the pilots used to get over the last line of flak. Forty-three thousand were built.

Mikulin AM-38F · V-12 · 46.7 L · single-speed supercharger geared for low altitude · 1,720 hp take-off, 1,500 hp at 750 m

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· WEAPONS AND SPECIALITY

Cannon, rockets, bombs — and the bomblet strip

Two 23 mm cannon and two of the fastest-firing machine guns of the war put about 4.6 kg of metal a second into whatever was ahead, for fifteen seconds of cannon fire. Under the wings hung rockets or bombs; from 1943 the four containers of PTAB shaped-charge bomblets were the weapon that mattered. None of it was accurate by modern standards. Numbers were.

· TRY IT

An engine that only breathes low down

The lab runs the AM-38F against altitude: enormous power at the height of the battlefield and a curve that collapses above 2,000 m. Compare it with the same lab set to the Spitfire and the reason for the Il-2’s 4,500 m ceiling is on the chart.

Readout

Weight of fire4.58 kg/s

Cannon share87 %

Seconds of fire15 s

Metal in this burst9.2 kg

Ilyushin Il-2 Shturmovik: the guns as carried on the main version; seconds of fire is the gun that runs dry first.