by Attack on Pearl Harbor: Strategy, Combat, Myths, Deceptions
These factors suggest that the Japanese aircrew should have been able to give a decent report as to where their target was located. But that leaves the fact that there is a significant disconnect between what was shown in the BDA report and the distribution of the attack effort extracted from the US records.
Two additional factors would have prevented dive-bomber attacks against Battleship Row. First, there was the huge amount of smoke covering the area. The prevailing wind blew the smoke from Arizona’s raging fires and the oil fires around Tennessee and West Virginia down the length of Battleship Row. Flaming oil eventually drifted down upon California, the southernmost battleship on Battleship Row, forcing her to be temporarily abandoned.
Photographs taken from Japanese aircraft show heavy cloud cover over the harbor, as do American photographs taken just before the arrival of the second wave and during the dive-bombers’ attack. The dive-bombers would have to either find holes through the clouds or dive through them to make their attacks, a very difficult situation. Some approached their targets under the cloud base, which gave them insufficient altitude to execute attacks as they had been trained.
The Japanese trained to execute a standard dive-bombing attack. The attack would begin with an approach to the target area at 10,000 to 12,000 feet. As they approached the target they would go into a gentle glide to increase airspeed and head for a point downwind of the target. They would arrive at the pitch-over point about a half-mile from the taret at between 6,400 to 9,600 feet altitude. They attacked in a 55 to 60 degree dive with 20 to 30 second intervals between aircraft in the shotai. The intervals were longer than in American doctrine, allowing following aircraft to correct for wind drift based on the splash of the previous bomb. Bomb release could be as low as 300 to 400 meters.
This technique required good visibility. Smoke and clouds like those over the harbor would prevent a conventional attack. If the dive-bombers wanted to attack Battleship Row they had to come in crosswind or with the wind, reducing bombing accuracy. With 80 to 90% cloud cover between 2,000 to 3,500 feet the dive-bombers had to either find a hole in the clouds or begin their attack from under the cloud layer, another departure from their usual practice. Witnesses noted that some dive-bombers appeared to shift targets in the middle of their dive. A lower pitch-over altitude also meant less time for target identification and aiming before weapon release.
The smoke boiling out of Battleship Row would also have suggested that those targets were already destroyed. The aircrews had been briefed to pass up such targets.
Possible Misidentification of Targets
Photographs show that many of the battleships rigged canvas awnings over their decks, shielding them from the radiant heat of the tropical sun. Tenders and auxiliaries also rigged awnings. This, coupled with the smoke and low cloud cover, could have confused target identification. American reports indicate that eleven D3A Vals released bombs against the tenders Tangier and Curtiss. They might have believed them to be battleships. If the attacks on Shaw, Curtiss, and Tangier were added to those attacking Pennsylvania, California, and Nevada, there would be a total of 45 dive-bombers reporting they had attacked battleships.
The Japanese aviators’ reports could have been sufficiently vague that the BDA team had to apply their own judgment. The concentration of hits reported on Battleship Row targets could have just been a consequence of smoke, a low ceiling, and vague reporting.
If this were the case, the magnitude of the errors was breathtaking.
A Purposefully Inflated BDA Report?
Three times as many GP bomb hits were claimed than actually achieved. The BDA Report claims more hits than were reported by the carriers. The officers on the flagship assessing the results increased the number of hits over what was reported by the aviators.
Those officers might have assumed that the dive-bombers would duplicate their training performance, and so “promoted” hits reported as “probable” to definite hits. This is a common occurrence documented in psychological studies of decision making: people tend to see what they expect to see. If the reports were not specific regarding the target’s location an assessors might have attempted to place the expected hits against specific targets based on smoke, fires, or photographic evidence. With a process like that, some additional bomb hits could have been assigned to Battleship Row. But the aviators reported only 13 probable hits, of which 11 appear to have been promoted by the assessors to definite hits. This is much less than the 21 hits assigned to Battleship Row targets.
It could be that aircrews were vague about where their targets lay. Bombers that attacked the tenders west of Ford Island might have misidentified them as battleships, and if in the rush to get an initial assessment to the command, reported target locations in an imprecise manner, giving the BDA team the flexibility to assign them to Battleship Row. But there were only 16 aircraft that attacked tenders, insufficient for 21 hits to be assigned to Battleship Row even assuming all were hits.
The last possibility is that the hits claimed in the BDA report were intentionally inflated to attribute an excellent performance to the dive-bombers.
Organizational Theory would suggest that such an action would require three kinds of authority: the authority of rank, the authority of position, and the authority of knowledge.
The man in charge of the BDA was the strike commander, Fuchida. He had the “authority of rank,” the senior man assigned to the damage assessment effort. He also had the “authority of position” as head of the strike and leader of the assessment group.
After delivering his attack as part of the first wave, Fuchida remained over the harbor. Fuchida observed the entire course of the attack by the second wave, and was not distracted by a requirement to make an attack of his own. He stated he was the last to leave Pearl Harbor after making a tour to note the results. He had the “authority of knowledge” as the one that could be expected to have the best overall picture of the results of the second-wave bombing attacks.
The combination of these three authorities would make his judgments the ruling authority in the BDA process. He was the one responsible for accepting an inflated number of torpedo hits, an overestimated number of AP bomb hits, and he had the authority and opportunity to do what he wished with the dive-bomber results. If he did not do it personally, he could have guided and influenced the group performing the assessment towards inflated results, something not hard to do, as this group would have been prone to see the results of their efforts in the best possible light.
The Japanese practice of having the strike commander responsible for collecting and collating the BDA assessment was faulty. In the US Navy, intelligence officers interviewed returning aviators and assembled a consolidated report. The process characteristically would result in a reduction in claims, as an individual aircraft’s results had to be corroborated by other aircraft. If a pilot claimed a hit and his attack was not observed by others, the claim was generally downgraded to a “probable.”
A process like this was not in place in the Imperial Japanese Navy. The strike aviators submitted their own claims, and the strike leaders consolidated the reports and made judgments under the supervision and guidance of the strike commander. They were not impartial observers.
Fuchida was responsible for the effort to collate all the data from the attack units. The reports and photographs from all the carriers were flown over to Akagi for the net assessment. He had assistance from Akagi’s senior flyers, and perhaps some of the bomber leaders flew over from the other carriers, although this last is not mentioned in the accounts of the post-battle evaluation. Fuchida headed the effort overall and personally was in charge of appraising the attack against the fleet, while the second-wave flight leader assessed the OCA effort against the airfields.
There were several psychological pressures on Fuchida.
Fuchida had personal interests in the D3A Vals’ performance. He was a “special friend” of LCDR Egusa,29 the leader of the second-wave dive-bombers. Naturall
y he would want to see his friend succeed. Egusa’s reputation was at stake. He would be embarrassed by a poor performance by the dive-bombers, as their leader and as the man responsible for their training.
Egusa could also be embarrassed by the poor target selection command decisions made by the dive-bombers’ leadership. He was directly involved in the decision to attempt to sink ships in the channel, which resulted in the attacks on Nevada (a poor weapons-target match and inadequate level of effort), and on what were identified as class “B” cruisers that were actually destroyers Dale30 and Helm. Class “B” cruisers, similar to the Omaha class, were not high on the target priority list.31 All of these attacks were poor weapon-target matches or poor target identification. If the final assessment reported a poor dive-bombing hit percentage, it would open the door to inquiries, and Egusa might be held responsible for using valuable bombs on targets too tough for the weapon, or targets too small to be worthwhile.
A poor performance by the dive-bombers might open up the floodgates of criticism. Genda and Fuchida might have a share of the blame thrown in their direction in their role as attack planners. Genda was Fuchida’s friend. Fuchida had assisted him in formulating the attack plan. Fuchida had also briefed the dive-bombers to be alert to an opportunity to sink a battleship in the channel, an effort that failed.
Lastly, a poor performance by the dive-bombers would also reflect poorly on the performance of Kido Butai as an offensive weapon system, something an air power advocate like Fuchida would deplore. Dive-bombers were one-third the aircraft and half the offensive punch of the fleet carriers. Aviators were still sensitive to the competition between carrier advocates and battleship gunnery specialists for leadership in the Imperial Navy, and were in competition with them for resource. To have half of the offensive punch of the carriers perform in an unsatisfactory manner would not have promoted the aviators’ cause. This is especially the case when it is considered that the torpedo bombers’ attack could be represented as a fluke that could not be repeated against a forewarned enemy at sea and free to maneuver and evade torpedoes.
Torpedo bombers were already assumed to be, in some aviation circles, ineffective. The Americans questioned their viability, at one period considering abolishing torpedo bombers. The carrier Ranger was built without facilities for torpedo bombers and was to carry only fighters and dive-bombers. If aviators expected the torpedo bombers would score few hits and suffer debilitating attrition from enemy AA fire, and if the dive-bombers were also found to be ineffective, then the carriers would have their credibility questioned in the Imperial Japanese Navy as well. Carriers’ effectiveness in anything but a surprise attack might be questioned. The Imperial Navy might look to build more battleships like Yamato and fewer carriers like Shokaku.
There was also another possible motive, an institutional motive. A poor showing by the dive-bombers would put that aviation sub-community under scrutiny. Careers could be threatened. The Imperial Navy’s commitment to dive-bombing might be questioned.
All these factors point to very serious consequences if the BDA Report stated that the dive-bombers did not perform as expected. Fuchida might have taken it upon himself, or he might have been directed by some higher authority, to change the hit numbers to forestall internal conflicts within the aviation communities and to make all the carrier aviation branches look good. Such an order might not be made explicitly, but in conversations and other ways such demands could clearly be made or implied.
These are all potential motives. There is no evidence to support or challenge these observations. They are only possibilities—but strong possibilities.
Fuchida had potential personal, social, professional, and institutional motivations for seeing the dive-bombers perform well. Fuchida was in position, through manipulating a few numbers, to help his friends, protect himself, protect the dive-bomber community, protect the concept of carrier striking forces, and protect naval aviation in general.
These problems could have been solved by “padding the returns.” Twelve GP bomb hits were assigned to Maryland, eight to California, three to an oil tanker that Fuchida assessed as “sunk,” and six to a cruiser, all hits that had not occurred. Other bogus hits were scattered about among targets at the naval shipyard. Two hits and “moderate damage” was also assigned to a “Class B Cruiser” that was actually the undamaged destroyer Dale. These inflated returns brought the score for the dive-bombers up to a hit percentage in line with their performance during training, and gave Egusa’s men justification to take pride in “their share” of the destruction of several targets.
These bogus hits were not arbitrarily assigned. It appears that they were assigned after careful consideration to ensure that the deception could be concealed to the largest extent possible.
Additional hits against ships on battleship row could be assigned because:
1) battleships were on the priority list for Egusa’s men, regardless of how inappropriate the weapons-target match;
2) there was so much smoke over Battleship Row, and the second wave dive bombers’ attacks so geographically scattered, that no one else could really have a full picture that might contradict Fuchida’s word;
3) the smoke along Battleship Row could be attributed to the effects of the additional GP bomb hits;
4) the dive-bombers attacked so many scattered and diverse targets over such a duration that, when seeing all the hits claimed against Battleship Row, the dive-bomber aircrews would probably just assume that aircraft from one of the other ships were responsible for those hits;
5) many dive-bomber pilots who attacked tenders or the floating drydock might have reported that they attacked battleships. Abe’s and Furuta’s accounts serve as examples. If their location report was vague, Fuchida would have taken the responsibility of assigning the attacks to likely battleship targets.
Dive-bombing attacks on Battleship Row would have been nearly impossible. There was dense smoke boiling out of Arizona, along with the burning oil on the water that caused the evacuation of the after part of Tennessee and of West Virginia and California. Photographs show that area to be totally obscured by smoke as high as 8,000 feet. Only California, on the extreme southern end of Battleship Row, peeked out from under the smoke clouds; apparently only California was actually attacked by one shotai of dive-bombers.
The disparate performance between the various carriers’ can also be explained. Akagi’s dive-bombers were given credit for 6% hits, while the other carriers were given credit for hit percentages between 78% and 94%. Fuchida was on board Akagi and had direct access to Akagi’s airmen, and they undoubtedly knew what they achieved and could be interviewed directly to provide reports of what they attacked and if their bombs hit. The leaders of Akagi’s dive-bombers likely assisted in formulating the BDA Report. It would be very difficult to manipulate the results of Akagi’s airmen, as they were literally looking over his shoulder. Fuchida would have little flexibility regarding Akagi’s reported results. However, the other carriers’ aviators could not immediately review the work. If hits were to be added to improve the D3A Vals’ overall score, they would have to be credited to the other carriers.
The number of torpedo hits credited in the BDA Report was larger than the aviators’ claimed. It was inflated apparently to give a hit for every torpedo dropped and one for every aircrew that returned, sparing anyone the embarrassment of failure, a critical consideration in Japanese society. This establishes in principle that the final BDA report numbers were manipulated, as it would be impossible to count torpedo hits from post-action photographs. Similarly, the results reported for the level bombers exceeded practice scores and exceeded the aviators’ own claims, indicating that someone on the flagship upped those numbers, too.
Aviators had a tendency to see hits where no hits occurred, or hits that were not their own, and report results that were serious exaggerations. Fuchida himself claimed two hits for his formation that did not occur. This is not an indictment of dishonesty, but rather
recognition that in high-stress environments the mind’s eye tends to see what it expects to see. The Japanese aviators at the end of the war suffered badly from this syndrome. According to their reports, Halsey’s Fifth Fleet was sunk several times over.
However, what is being extracted now is different. The question is not only the hit percentage, but the location of the claimed hits compared to the truth on the ground of what they actually attacked.
Either about half the second-wave dive-bombers’ aircrews misrepresented or mistook the targets in which they attacked and claimed hits that did not occur, or Fuchida signed a report that misrepresented their targets and results. Occam’s razor might come into consideration: “All other things being equal, the simplest answer is the most likely.” What is simpler, a collusion authored by a large group of unassociated personnel, or a few tweaks to the report under the authority of one individual?
If Fuchida saw the need to report some 30 additional 250kg GP bomb hits, how could it be done? Hits could not be claimed where photographs did not show damage. Some hits could be assigned to targets that were actually attacked, but the battle damage assessment photographs would not support too many hits since the damage simply was not there. Some hits could be assigned to the tanker that disappeared off the photographs and could be claimed as sunk at its moorings when the mooring area became totally obscured by fires, and to the “cruisers” Dale and Helm attacked in the channel.
But even with extra hits assigned to these targets, the photographic evidence would still not support 30 additional hits. The hits had to be assigned to something that had been destroyed, could likely be thought of as absorbing many hits to prevent accusations that bombs were wasted on destroyed ships, and to targets that were on the priority list to prevent investigations on why inappropriate targets were attacked, and to targets that were obscured in the photographs so that individual smoking holes could not be counted.
