Yokosuka D4Y Suisei
Operational History

Lacking armor and self-sealing fuel tanks, the Suiseis did not fare well against Allied fighters. They did, however, cause considerable damage to ships, including the carrier USS Franklin, which was nearly sunk by a single D4Y.

The D4Y was operated from the following Japanese aircraft carriers: Chitose, Chiyoda, Hiyō, Junyō, Shinyo, Shōkaku, Sōryū, Taihō, Unryū, Unyō and Zuikaku.

The D4Y1-C reconnaissance aircraft entered service in mid-1942, when two of these aircraft were deployed aboard Sōryū at the Battle of Midway, where both were lost when Sōryū was sunk.

During the Battle of the Marianas, the D4Ys were engaged by U.S. Navy fighters and shot down in large numbers.as faster than the Grumman F4F Wildcat, but not the new Grumman F6F Hellcat. The Japanese aircraft were adequate for 1943, but the rapid advances in American materiel in 1944 (among them, the introduction in large numbers of the Essex-class aircraft carrier) left the Japanese behind. Another disadvantage suffered by the Japanese was their inexperienced pilots.

The U.S. Task Force 58 struck the Philippine airfields and destroyed the land air forces first, before engaging Japanese naval aircraft. The result was what the Americans called "The Great Marianas Turkey Shoot", with 400 Japanese aircraft shot down in a single day. A single Hellcat pilot, Lieutenant Alexander Vraciu, shot down six D4Ys within a few minutes.

One D4Y was said to have damaged the battleship USS South Dakota.

Leyte and Philippines
The D4Y was relegated to land operations where both the liquid-cooled engine D4Y2, and the radial engine D4Y3 fought against the U.S. fleet, scoring some successes. An unseen D4Y bombed and sank the Princeton on 24 October 1944. D4Ys hit other carriers as well, by both conventional attacks and kamikaze actions. In the Philippines air battles, the Japanese used kamikazes for the first time, and they scored heavily. D4Ys from 761 Kōkūtai may have hit the escort carrier USS Kalinin Bay on 25 October 1944, and the next day, USS Suwannee. Both were badly damaged, especially Suwannee, with heavy casualties and many aircraft destroyed. A month later on 25 November, USS Essex, Hancock, Intrepid and Cabot were hit by kamikazes, almost exclusively A6M Zero fighters and D4Ys, with much more damage. D4Ys also made conventional attacks. All these D4Ys were from 601 and 653 Kkūtai.

Yokosuka D4Y Suisei Comet stripped and abandoned. WRG #: 0000144
Yokosuka D4Y Suisei "Comet" stripped and abandoned.
[Source: Jack Cook Collection]

In defense of the homeland
Task Force 58 approached southern Japan in March 1945 to strike military objectives in support of the invasion of Okinawa. The Japanese responded with massive kamikaze attacks, codenamed Kikusui, in which many D4Ys were used. A dedicated kamikaze version of the D4Y3, the D4Y4 with a non-detachable 800 kg bomb attached in a semi-recessed manner, was developed. The Japanese had begun installing rocket boosters on some Kamikazes, including the D4Y4 in order to increase speed near the target. As the D4Y4 was virtually identical in the air to the D4Y3, it was difficult to determine the sorties of each type.

Yokosuka D4Y3.
[Source: Unknown]

Carriers USS Enterprise and Yorktown were damaged by D4Ys of 701 Wing on 18 March. On 19 March, the carrier Franklin was hit with two bombs from a single D4Y, which then escaped despite heavy anti-aircraft fire. Franklin was so heavily damaged that she was retired until the end of the war. Another D4Y hit the carrier USS Wasp.

On 12 April 1945, another D4Y, part of Kikusui mission N.2, struck Enterprise, causing some damage.

During Kikusui N.6, on 11 May 1945, USS Bunker Hill was hit and put out of action by two kamikazes that some sources identify as D4Ys. This was the third Essex-class carrier forced to retire to the United States to repair.

Night fighter
The D4Y was faster than the A6M Zero and some were employed as D4Y2-S night fighters against Boeing B-29 Superfortress bombers late in the war. The night fighter conversions were made at the 11th Naval Aviation Arsenal at Hiro. Each D4Y2-S had their bombing systems and equipment removed, and replaced with a 20 mm Type 99 cannon with its barrel slanted up and forwards, in a similar manner to the German Schräge Musik armament fitment (pioneered in May 1943 on the Nakajima J1N by the IJNAS) installed in the rear cockpit. Some examples also carried two or four 10 cm air-to-air rockets under the wings; lack of radar for night interceptions, inadequate climb rate and the B-29's high ceiling limited the D4Y2-S effectiveness as a night fighter. Little is known of their operations.

The Complete Encyclopedia of World Aircraft, 1997, Barnes & Nobles Books, ISBN: 0 7607 0592 5