The D4Y was one of many Japanese aircraft that arrived too late to be truly effective in it’s original design role, in this case as a carrier based dive bomber. It wasn’t ready in time to take part in the battle of Midway, and many of the first units to be trained with the new aircraft suffered devastating losses when used as a land based bomber during the disastrous attempt to defend Rabaul using carrier aircraft late in 1943. More than two thirds of the carrier aircraft involved were lost in this period, taking with them many of the last well trained Japanese naval aviators.
The section of the battle of the Philippine Sea is interesting, as it is based around the eyewitness account of Lt Zenji Abe, one of the few Japanese pilots to actually attack a US carrier during the battle, and who survived the destruction of his aircraft as he landed at Rota airfield. This was the one occasion on which the D4Y was used in large numbers in a naval battle, and it failed to achieve anything.
After this the D4Y was almost exclusively used from land bases. During the attempt to defend the Philippines the type achieved it’s greatest success as a conventional bomber, sinking the light carrier USS Princeton, but the D4Y achieved most of its major successes as a kamikaze.
The largest chapter looks at the D4Y’s use as a suicide bomber. We start with an examination of the reasons for this new tactic, where it becomes clear that by 1944 formal kamikaze attacks weren’t that much more dangerous for the Japanese aircrews as attempts on conventional attacks, which tended to lead to very high casualty figures without actually achieving anything. During the battle of the Philippine Sea at least two thirds of the carrier aircraft that actually found the Americans were shot down. Obviously kamikaze attacks also led to high losses (although not perhaps quite as high as one might expect), and had a greater chance of doing some real damage to the American fleet. Next comes the complete text of a late war US report into kamikaze tactics, which demonstrates that they were rather more organised than one might think. We then reach the account of the D4Y as a suicide bomber, a role in which it inflicted the most damage on the US fleet. One problem here is firmly identifying which aircraft type was involved in each attack, but there is clear evidence that the D4Y hit one carrier and one heavy cruiser in the Philippines, the Saratoga off Iwo Jima, and the Franklin (in a conventional dive bomber attack)and a destroyer during a raid on Japan, and the Hancock off Okinawa. There is a slight tendency to turn this chapter into a general account of kamikaze attacks, but we do get enough material on the role of the D4Y.
The much shorter final chapter looks at the use of the D4Y as a night fighter, in the campaign against the B-29 attacks on Japan, a role in which it appears to have been fairly successful.
This is a well written account of the combat career of this capable dive bomber, and gives us an insight into the struggles of the Imperial Japanese Navy after the end of the early years of victory.
1 – Design and Development
2 – Battle of Midway
3 – Truk and the Marianas
4 – Formosa and the Philippines
5 – Kamikazes
6 – D4Y2-S Nightfighter