Aichi D3A “Val”

In 1936 the Imperial Japanese Navy issued a requirement for a new carrier-based dive bomber to replace its biplanes. Aichi’s answer drew openly on German practice — the company had close ties to Heinkel, and the prototype’s elliptical wing owed a clear debt to the elegant Heinkel He 70. First flown in January 1938, it entered service as the D3A and would receive the Allied reporting name “Val”.

It looked, from the outset, like a design already behind the times. Where the American Dauntless and most modern types retracted their wheels, the D3A kept a fixed, trousered undercarriage — a decision made to save weight and complexity, and to simplify the stresses of dive-bombing. The result appeared antiquated, and yet in the hands of the pre-war Navy’s superbly trained crews it would prove, for a time, devastatingly effective.

The D3A was a clean, compact two-seater built around a Mitsubishi Kinsei radial. The early D3A1 had about 1,000 hp; the later D3A2 (Model 22) raised that to some 1,300 hp and lifted top speed to roughly 430 km/h. Large dive brakes under the wings let it hold a steady, near-vertical dive, and its fixed gear — for all that it looked dated — gave a rock-solid aiming platform.

Its offensive load was modest: a single 250 kg bomb on a crutch under the fuselage, swung clear of the propeller in the dive, plus two 60 kg bombs under the wings. Defence was two fixed 7.7 mm guns forward and one flexible gun for the rear crewman. Lightly built and responsive, the Val was surprisingly nimble once its bomb was gone — pilots sometimes stayed to dogfight, and a few even claimed aerial victories.

On the morning of 7 December 1941, Vals were in the vanguard of the attack on Pearl Harbor. Dive bombers of the first wave struck the airfields at Hickam, Wheeler and Ford Island to smash American air power on the ground, while the second wave, built around a large force of D3As, pressed home against the warships through thickening anti-aircraft fire.

It was the opening act of a rampage. In the months that followed, the six carriers of the Kidō Butai ranged unchecked from Hawaii to Ceylon, and the Val was their hammer — the aircraft that put the bombs on the decks of the enemy’s ships. For half a year the Imperial Japanese Navy’s dive-bomber crews were arguably the finest in the world.

The peak came in the Indian Ocean raid of April 1942. On 5 April, D3As caught the British heavy cruisers HMS Cornwall and HMS Dorsetshire at sea and sank them both in minutes, reportedly landing an astonishing proportion of their bombs on the twisting, evading ships. Four days later, on 9 April, they found the aircraft carrier HMS Hermes and sent her to the bottom as well.

The hit rates the Val achieved in those weeks — commonly cited as well over 80 percent — were among the highest of the entire war, a level of accuracy that reflected years of peacetime training as much as the aircraft itself. No Axis aircraft would sink more Allied warships than the D3A, and much of that tally was written in these few extraordinary months.

The turn came quickly. At Coral Sea in May 1942 and above all at Midway in June, the Val’s carriers were destroyed and — more importantly — its irreplaceable veteran aircrew began to die in numbers Japan could not make good. Through the grinding carrier battles of Eastern Solomons and Santa Cruz, the D3A still bit hard, helping to cripple American carriers, but each engagement thinned the ranks of the men who had made it so deadly.

By 1943 the fixed-gear dive bomber was thoroughly outclassed, and the faster Yokosuka D4Y “Judy” was arriving to replace it. Yet the Val soldiered on to the end, relegated to training and second-line units and, finally, expended in kamikaze attacks. About 1,490 were built in all.

The Aichi D3A is a study in how much the crew matters. On paper it was obsolescent before the war even began — slow, lightly armed, its wheels hanging in the wind. In practice, flown by the elite of the pre-war Navy, it opened the Pacific war and ran up a record no other Axis aircraft could match: more Allied warships sunk than any other.

Its story is inseparable from that of the men who flew it. When the veteran crews were gone — burned away at Midway and in the Solomons — the Val declined as sharply as they did, from the terror of the Indian Ocean to a training hack and a suicide weapon in the space of three years. Few aircraft rose so high, or fell so far, so fast.

• René J. Francillon, Japanese Aircraft of the Pacific War (Putnam).
• Osamu Tagaya, Aichi 99 Kanbaku ‘Val’ Units 1937–42 (Osprey, Combat Aircraft).