Douglas C-47 Skytrain (1943): the war’s logistics

1943·260 km/h·28 troops or 2,700 kg·2× R-1830 Twin Wasp radials, 1,200 hp each·2,600 km·10,174 (plus ~5,000 under licence)

· THE STORY

The airliner that won the war

The C-47 was a DC-3 airliner with a big cargo door, a reinforced floor and benches for 28 paratroopers, and it is on this list because the machines that decide wars are not always the ones with guns. It dropped the paratroops over Sicily and Normandy and Arnhem, flew fuel and ammunition over the Himalayas into China when Japan had closed every road, towed the gliders, brought out the wounded, and kept Bastogne alive. Eisenhower is usually quoted listing it with the bulldozer, the jeep and the truck as the equipment that won the war.

260 km/hCruise28 troops or 2,700 kgPayload

· WHY IT MATTERED

An airliner with a cargo door

The DC-3 had already made airlines profitable before the war; the C-47 changed almost nothing that mattered. A wider door, a stronger floor, hooks for glider towing. Ten thousand were built in the United States and thousands more under licence in the Soviet Union and Japan, on both sides of the war.

GO DEEPERThe DC-3 it was built from →Flying the Hump →

· WHY IT MATTERED

The Hump

From 1942 the only way into China was over the eastern Himalayas at 4,500–5,000 m, in weather that killed more crews than the Japanese did. The C-47B was built for that route: two-speed superchargers that gave its engines back the air the altitude took away, on a run that moved 650,000 tonnes in three years.

· WHY IT MATTERED

Normandy by air

On the night before D-Day more than 800 C-47s dropped some 13,000 American paratroopers behind Utah beach; by the end of the first days over 50,000 men had arrived by parachute and glider. Every one of those aircraft was unarmed, flying slow and low through flak.

· THE ENGINE

The most-produced aero engine in history

The Twin Wasp was not the most powerful radial of the war, nor the most advanced. It was the one that ran: 173,618 were built, more than any other aero engine ever, and they powered the B-24 and the Wildcat as well as the C-47. Two of them made 2,400 hp on take-off and burned about 400 litres an hour at cruise. The B model’s two-speed supercharger existed for one route, the Hump, where a single-speed engine ran out of air.

2× Pratt & Whitney R-1830-92 Twin Wasp · 14-cylinder two-row radial · 30.0 L · single-stage supercharger (two-speed on the C-47B) · 1,200 hp each

GO DEEPEROpen the full demo →

· WEAPONS AND SPECIALITY

Twenty-eight men, or three tonnes

The C-47 carried nothing to defend itself and everything else: paratroopers with their kit, jeeps in pieces, fuel drums, wounded on stretchers. Its speciality was arriving. At 260 km/h it was slower than everything that could shoot at it, and it flew anyway, night after night.

· TRY IT

Payload against range, and a mountain pass

The lab’s range tab is set to a C-47B: the fuel it can carry against the cargo it can carry, along one line, and what a 4,600 m pass on two 1,200 hp engines leaves in hand with the supercharger in high gear or low.

Readout

Power, 2 engines2,102 hp

Per engine1,051 hp

True airspeed360 km/h

Service ceiling8,000 m

A simplified model calibrated to the published rating and top speed — the shape of the curve is the point, not the third decimal.