[2][3][4] In mid-1936, the Japanese Navy issued the 11-Shi specification for a monoplane carrier-based dive bomber to replace the existing D1A biplane then in service.

Power was increased by replacing the Hikari with the 626 kW (839 hp) Mitsubishi Kinsei 3 in a redesigned cowling, and the vertical tail was enlarged to help with the directional instability.

The wings were slightly larger in span and the outer sections of the leading edges had wash-out to combat the snap rolls, and strengthened dive brakes were fitted.

The directional instability problem was finally cured with the fitting of a long dorsal fin-strake which started midway down the rear fuselage, and the aircraft actually became highly maneuverable.

The observer/navigator position was equipped with a Type 97 Mk1 drift sight, which was a long vertical tube located in the front-left of the observer's seat.

The D3A1 first saw combat operation in November 1939, one month prior to its official acceptance as the Navy Type 99 dive bomber.

These D3A1s were commanded by Lieutenant Sadamu Takahashi and supported the Imperial Japanese Army in the capture of Nanning, which was intended to cut the supplies coming from French Indochina.

After the invasion of Indochina in autumn 1940, 14th Air Group operated at Hanoi and flew missions against Kunming and Burma Road.

D3A1 dive bombers scored over 80% hits[14] with their bombs during attacks on two heavy cruisers and an aircraft carrier during the operation.

Before the Indian Ocean raid, the established doctrine regarding attacks against ships was to arm all D3A1 dive bombers with semi-AP bombs.

When British heavy cruisers were spotted soon afterwards, the reserve force was sent with a portion of D3A1 dive bombers armed with land bombs.

In the subsequent attack, land bombs unintentionally proved very effective in suppressing the anti-aircraft fire from the ships.

Discounting the Pearl Harbor strike, which also used the B5N for level bombing and torpedo attacks, D3A dive bombers were credited with sinking the following Allied warships (partial list):[18][19] As the war progressed, there were instances when the dive bombers were pressed into duty as fighters in the interceptor role, their maneuverability being enough to allow them to survive in this role.

By then, many D3A1s and D3A2s were operated by training units in Japan, and several were modified with dual controls as Navy Type 99 Bomber Trainer Model 12s (D3A2-K).