Archie to SAM: A Short Operational History of Ground-Based Air ...

ANTIAIRCRAFT DEFENSE THROUGH WORLD WAR II
four shells. In the proximity fuze’s first combat engagement a
year later, the USS Helena downed a Japanese bomber with its
second salvo. The Navy estimated that the proximity fuzes increased
AAA effectiveness three to four times. The fuze helped
account for the high percentage of Japanese aircraft claimed
by the 5-inch/38-caliber guns, numbering 31 percent through
the first half of 1944. 94
Japanese Antiaircraft Artillery
Japanese AAA lagged behind the other major powers throughout
the war. The Japanese lacked the technological and manufacturing
base to deal with their air defense problems and to
make good their deficiencies. In addition, the Japanese received
only limited assistance from the Germans and failed to
fully mobilize their civilian scientists. 95
The most widely used Japanese heavy flak piece was the 75
mm type 88 that entered service in 1928. It fired a 14.5-pound
shell at a muzzle velocity of 2,360 fps to 23,550 feet but was
inaccurate above 16,000 feet. The Japanese stuck with this
gun throughout the war, while the Americans, British, and
Germans went to larger and better performing weapons. Not
that the Japanese did not try to upgrade their weapons—they
produced an improved 75 mm gun (75 mm type 4) in 1944 but
built only 65 and got few into action. Likewise, the Japanese
put a 120 mm gun into production in 1943 but built only 154.
Only two 150 mm guns saw service. The Japanese also used a
few 88 mm naval guns. 96
In 1941, the Japanese deployed 300 antiaircraft guns in defense
of the home islands. By March 1945, they deployed
1,250, and, by the end of the war, over 2,000. As might be expected,
the Japanese concentrated the largest number of their
heavy guns (in all 509 to 551) around Tokyo: in August 1945,
150 naval 88 mm guns; 72 120 mm guns; and two 150 mm
guns. Thus, compared with the Germans, the Japanese deployed
fewer and less-capable guns. In addition, Japanese radar
was far behind German radar. The Japanese did not capitalize
on German technology but primarily relied on technology from
captured American and British equipment.
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