The USN, and anyone else in the dive bombing business, could tell you that in those days once a plane started its dive, it was very difficult for AA to shoot down . . . mostly a fire direction and time on target problem that, with locally controlled fire such as the Japanese employed through most of the war, generally leads to a bad defense solution. In other words, if the dive bomber knows his business, he’s coming almost straight down on a target, hopefully lined up straight with the direction of travel (this reduces HIS deflection problem) which probably has – I hesitate to use the word “small” caliber, but what I mean is something in the 12 mm to 20 mm range - a small caliber defensive suite which cannot be elevated to an angle which would allow for effective return fire.
In the overall scheme, Japanese AA didn’t appear to be all that effective anywhere during the war. Using official USN statistics, compiled circa 1947, in the 1941-42 period, US carrier based-based aircraft flew some 1976 sorties attacking targets, encountering AA on 1238, or 62.6% of attack sorties. In the 1238 attack sorties meeting AA, 113 planes suffered AA hits. 47 of those were lost and 66 returned damaged; thus 41.6% of aircraft hit byAA fire were lost. Overall, however, this works out to only 9.1% of attacking aircraft suffering AA hits, with only 3.8% shot down. And this was Japanese naval AA’s best annual effort; as the war progressed, their results were increasing less effective despite increases in numbers of guns, especially land-based, and resultant volume of AA fire.
More recent research (see Parshall & Tully “Shattered Sword”) indicates that Japanese AA fire at the Battle of Midway accounted for only but two US aircraft during the various attacks on the Japanese carriers. Of the 47 losses noted above in the USN post war compilation, 24 were counted to have occurred during the Battle of Midway.
If we now know that 22 AA losses ascribed in the 1947 as to Japanese AA fire at Midway were actually the result of some other cause (probably to CAP action), then that would mean that USN AA loses for 1941-1942 actually were not more than 25, or 27.4% of those receiving AA hits (reduced accordingly from 113 to 91). In turn, the number of percentage of attacking aircraft suffering AA hits, overall, reduces to 7.3% and only 2.0% shot down. Either that or there were more than a few planes lost somewhere away from the immediate area of the Kido Butai whose loss was the result of AA damage. A little something to think about.
Official statistics on US losses for the Battle of Midway period are: 261 carrier-based (including strike escorts) and 59 land-based action sorties attacking Japanese ships for a total of 320 attacking sorties, with a total of 24 aircraft (20 carrier-based and 4 land-based) lost to AA, or 7.5% of all attacking aircraft. Total action sorties for the time period were 387 for carrier-based aircraft and 101 for land based. Losses credited to Japanese aircraft against total carrier-based sorties were 42, or 10.9%. For total land-based sorties, losses credited to Japanese aircraft were 33 or 32.7%. Total losses credited to Japanese aircraft: 65 aircraft or 15.4% of all action sorties. Total carrier-based operational losses were 16 (4.1% of carrier sorties).
