by Attack on Pearl Harbor: Strategy, Combat, Myths, Deceptions
A second alternative is a middle ground between the two. Fuchida may have received reports that were vague and subject to interpretation. In the background, operating in his subconscious, were all the factors mentioned previously: the desire to support his ally, the dive-bombing community, and carrier aviation in general by making the dive-bombers’ performance look good. There were also his expectations, conditioned by the long training period, which made him expect to see 40 to 50 hits by the dive-bombers. His inherent cultural bias was not to call down criticism on his fellow aviators or question claims. He did not want to cause the dive-bomber crews any embarrassment by suggesting that their performance was poor. Consequently, he was psychologically primed to see 50 hits. All the imperatives mentioned above would drive him to look hard for those 50 hits. A second explanation is that, with all the conditioning from the long days of training and planning, his mind would make him willing to see the additional hits on the scantest of evidence.
So, the exaggerated effectiveness of the second-wave dive-bombers recorded in the BDA report to the Emperor could have been the result of:
A) the fog of war,
B) a purposeful falsification of data, or
C) a subconscious predisposition to see hits where there were none.
In the absence of definitive evidence, readers must decide for themselves which case is the more compelling.
Other Comments on the Accuracy of the Japanese Battle Damage Assessment
The underestimated damage on Nevada is understandable. She was hit by only one torpedo, and sank well after the strike departed. Had the mistaken flooding of the magazine and the progressive flooding not occurred, the assessment of moderate damage would have been accurate.
The same held for California. Under normal combat circumstances two torpedo hits would not have been enough to sink her.
The assessment that Tennessee was sunk by three 800kg AP bomb hits is questionable. It might have been prompted by the burning oil released from Arizona that engulfed her at the end of the second-wave attacks. The heat from these external fires was so intense that fires were started in some of Tennessee’s internal compartments, and her magazines were flooded as a precautionary measure. The Japanese probably thought that Arizona’s magazine explosion was actually Tennessee, as the assessment of the ship in Arizona’s berth was that she was only “seriously” damaged.
Vestal was misidentified as an oiler and assessed as sunk by a single AP bomb. Vestal had moved during the lull between the attack waves. Presumably she was in photographs of the attack by the first wave, and absent from photographs made by the second wave, and this was used as justification for a claim she was sunk. Like Neosho, if she would have sunk much of her superstructure would have remained above the water, so this was a poor assessment.
The net assessment was remarkably accurate with respect to the battleline and poor with regards to cruisers and auxiliaries. Compared to some of the later battles when the Japanese pilots returned wildly optimistic reports on the damage they inflicted, the overall assessment of the Pearl Harbor attack against the mission-critical targets was good, even though some of the details were exaggerated.
Most of the opposition to the Japanese torpedo bombers came from .50-cal water-cooled machine guns. Shown is a battery mounted on Enterprise at the Battle of the Coral Sea. The gun sight is not mounted. The white liquid splashed on the gun mounting and catwalk is protein foam, used for firefighting. The loader, to the left of the gunner, has cans of ammunition reloads at his feet. Guns like this on destroyers and battleships were responsible for four of the five B5N Kate bombers shot down. Source: Naval Archives, Washington DC
Wisconsin outboard of the salvaged Oklahoma. The Japanese could choose to fight Oklahoma on the open seas, or attack Pearl Harbor, delay a fleet encounter, and face Wisconsin later in the war. Either choice would likely have led to defeat. Source: Naval Archives, Washington DC
Pearl Harbor, 30 October 1941, looking south, with the channel to the open sea at the top. This is the view that the Japanese should have seen from their planned IP north of the harbor. B5N Kate torpedo bombers would then have split east and west to attack Battleship Row and the carrier anchorage nearly simultaneously. Source: Naval Archives, Washington DC
An A6M Zero fighter plane. This photograph is from a set of recognition photographs taken of a captured A6M Zero taken in 1943. Source: Naval Archives, Washington DC
A B5N Kate carrier attack bomber, from a series of recognition photographs of a captured plane taken in 1944. A torpedo or up to three 250kg bombs could be slung externally under the fuselage. Source: Naval Archives, Washington DC
Two Japanese B5N Kate carrier attack bombers in formation. This is a Japanese photograph taken in 1939. Source: Naval Archives, Washington DC
A B5N Kate carrier attack bomber taking off from a carrier early in the war. This photograph was taken from an early WWII Japanese newsreel. Source: Naval Archives, Washington DC
A pre-war photograph of Battleship Row (top right), the Supply Base (center, on the peninsula), and a portion of the Submarine Base (lower left), and the edge of the shipyard piers (upper left) along the Southeast Loch. All but a few attackers avoided hopping the Supply Base and instead followed the loch past the shipyard to attack the southern end of Battleship Row. Source: Naval Archives, Washington DC
The attack route past the shipyard piers. The best approach would have been to arrive in echeloned waves with 50 yards between aircraft, with each aircraft attacking the ship to the right of that attacked by the previous aircraft. This would have better distributed the attack and split the defensive AA fire.
With a 10 to 15 knot crosswind, a bomber would encounter turbulence over the fuel storage tanks and an alternating zone of lift over the warming ground and the relatively colder water. The warehouses had to be cleared by only 20 feet. Past the warehouses the pilot would have 5 to 6 seconds to establish the right weapons delivery altitude, attitude, and airspeed.
A late 1941 photograph showing Hickam Field, a fuel tank farm, and the Naval Shipyard. To the right is the channel leading to the open sea at the top of the photograph. The channel was 400 yards wide. Source: Naval Archives, Washington DC
A 600-foot plume of water is next to Oklahoma. A torpedo bomber is above Neosho. Another can be seen over the Naval Shipyard, in a left turn to line up for a run down the loch, possibly a Hiryu or Soryu bomber cutting into Kaga or Akagi’s stream of attackers. Source: Naval Archives, Washington DC
Leaking black oil covers the water around Oklahoma and West Virginia. Note the two splashes in the water on Arizona’s starboard quarter, and one in line outboard of Vestal, from high-altitude AP bombs. Of the other two bombs from this formation, one hit Vestal and one hit Arizona. Note that there is no discernable signature from the hits. Source: National Archives at College Park, MD
California after the first wave has departed. She is listing and near to settling onto the bottom. Note all the debris in the water, from the capsized Oklahoma and Arizona’s explosion. Flotsam like this, drifting with the current, was likely the source of many of the reported submarine and periscope sightings. Source: Naval Archives, Washington DC
California in drydock, showing the damage produced by one aerial torpedo. The explosion did not penetrate the ship’s anti-torpedo defenses. California’s belt armor, 14 inches thick on top tapering down to 8 inches above the hole, does not appear to be damaged or deformed by the explosion. The bilge keel, lower left, is bent down in the vicinity of the hit. Source: Naval Archives, Washington DC
Pearl Harbor, ~0900. A more famous version of the scene telescopes in on the smoke pouring out of Battleship Row. Heavy cloud cover disrupted the dive-bombers’ attack. Neosho is in the center of the channel and easily visible. Fuchida, overhead observing the attack, should have noted that ship’s movement. Source: Naval Archives, Washington DC
A photograph taken during the second wave attack on the fleet. Note the heavy cloud cover. The small black smudge
s are AA shell bursts. A dive-bomber can be seen to the left about two-thirds of the way up the photograph, silhouetted against the clouds. Source: National Archives at College Park, MD
A D3A Val after releasing its bomb. The dive brakes under the wings are extended. The bomb release yoke or bukadan-ka (bomb rack) is extended under the fuselage. The yoke, called by Americans the “trapeze,” guides the bomb away from the aircraft’s propeller. Source: Naval Archives, Washington DC
A captured Japanese photograph of Hickam Field and Pearl Harbor through a break in the clouds. In the upper left is the dark fuselage of a B5N Kate. Smoke is rising from Battleship Row, right, and from the Shaw in drydock, left. Source: Naval Archives, Washington DC
Taken before the arrival of the second wave, this photograph shows California listing to port, with Neosho backing out into the channel. Neosho is at 75% load and is showing about 15 feet of freeboard amidships. Neosho’s bottom was about eight to ten feet above the harbor bottom. If she was sunk, some of her main deck and all of her superstructure would have remained out of the water. Source: National Archives at College Park, MD
A Japanese bomber, identified as one of Kaga’s D3A Val dive bombers, shot down over Pearl Harbor and in the process of salvage. The long tube above the fuselage forward of the cockpit is the bombsight telescope. The bomber’s streamlining “spats” encasing the landing gear and tires have either been removed or were knocked off in the crash. Source: National Archives at College Park, MD
Neosho departing from her Ford Island berth prior to the arrival of the second wave, showing how visible this movement would have been to newly arriving aircraft. Note also the very heavy layer of cloud cover arriving from over the mountains in the background. Smoke is coming out of California apparently due to a fire on the main deck starboard side. Many small boats and craft are near the battleships—over 20 boats and craft are visible. Had the dive-bombers attacked Battleship Row, bomb misses would have sunk many of these boats. Source: Naval Archives, Washington DC
This photograph shows Neosho nearing the center of the channel. The burning oil from Battleship Row that will eventually engulf California is beginning to move south with the current. The cloud cover is prominent. Source: National Archives at College Park, MD
Burning oil drifts toward California. The oil totally obscures Neosho’s former berth. Any Japanese photograph taken at this time might lead them to believe that the oiler had been sunk. Source: Naval Archives, Washington DC
West Virginia, sunk, is sitting on the harbor bottom outboard of Tennessee. Most of West Virginia’s main deck and all of her superstructure remain above the water. Had Neosho been sunk, her superstructures would have similarly remained visible. Source: Naval Archives, Washington DC
The fuel oil storage tanks adjacent to the Submarine Base. Note the tank dikes, sized to contain the entire contents should a tank rupture. Some of the tanks have been camouflaged with simple paint patterns. One tank is painted to look like a building. Source: Naval Archives, Washington DC
A view of the Naval Shipyard during wartime. The piers are adjacent to the industrial area encompassing nearly 500 acres. To the upper right is the southern end of Battleship Row, with one berth occupied by an Essex class carrier. Source: Naval Archives, Washington DC
The controversial “midget submarine in the picture,” shot from a Japanese bomber. The Japanese caption: “Thanks to the blessings of heaven and the will of the gods the sky opened up suddenly over the Hawaiian Naval Base of Pearl Harbor, and below our eyes were ranged in rows the enemy’s capital ships.” After describing the type and class of each ship in detail, the caption continued: “Our Sea Eagles’ determined attack had already been opened, and a column of water from a direct torpedo hit on a Maryland Class is rising. On the surface of the water concentric waves are traced by the direct torpedo hits, while murky crude oil flows out. The three bright streaks between the waves are torpedo tracks.” The Japanese examined the photograph closely and did not mention a midget submarine. American copies might be marred. Sailors in a launch caught in the photo near the splashes did not see a midget submarine. Source: Naval Archives, Washington DC
Utah in the process of capsizing after two torpedo hits. Toland’s assertion that Utah was attacked because she “looked like a carrier” is clearly wrong. Japanese aviators stated that Utah was mistaken for an operational battleship. Source: Naval Archives, Washington DC
CHAPTER NINE
WHAT MIGHT HAVE BEEN: ALERTED PEARL HARBOR DEFENSES
Initial Conditions
The US Army was responsible for the defense of the Pearl Harbor area, and Oahu in general. On 7 December the Army air defenses were in a complete stand-down, totally unready. This contrasted with the previous weeks, where the defenses were at high alert, with pilots standing by their aircraft, fighter patrols aloft at daybreak, and AA guns in position with live ammunition.
As early as 14 June 1940 the Army was practicing alerts for the defense of the islands. Lieutenant General Herron wrote of it in a letter to the Army Chief of Staff, General Marshall:
I have just come from seeing the dawn patrols take the air, and the anti-aircraft men roll out of the blankets at the first gray light at the sound of the Klaxon and stand at their guns…. I have been highly gratified with the promptness and precision with which the planes get off the ground every morning promptly at 4:30. It is further encouraging to see the discipline and quiet efficiency among the ground crews. It is my belief that the Air Corps here comes on well…. A week ago today I gave the command for a surprise alert, which went off smoothly and efficiently.1
In the months before the attack the Army had constructed an aircraft warning service system patterned after that used by the British during the Battle of Britain. The full system consisting of radar and human observers connected to an Aircraft Information Center (AIC), which would control the pursuit squadrons and air defenses. The AIC was successfully tested on 27 September 1941, more than two months before the raid. In that exercise, carrier aircraft playing the part of an enemy raiding force were detected 84 miles from Oahu, giving the defenders 40 minutes to react before the attacking planes went “feet dry,” and another 10 minutes before they reached Pearl Harbor. Within six minutes Army pursuit aircraft were aloft. The raid was intercepted 30 miles offshore.2
This was not a fully realistic test. It was scripted and the participants alert and ready to fly at the beginning of the exercise. There were still deficiencies, such as the fact that the system lacked the ability to differentiate hostile from friendly tracks. But it was a system fully capable of detecting a major carrier-launched strike with enough warning to allow the defenders to be manned and ready to receive it.
With the excuse that they lacked officers to man the center, Lt. General Short and Admiral Kimmel decided to wait until after the war began to place the AIC in operation.
On 7 December one of the system’s radars (operating beyond its scheduled time, for training) picked up the Japanese strike 136 miles north of Oahu. Before that, it had tracked the two Japanese reconnaissance floatplanes. Had the AIC been operational, the fleet and army forces would have had approximately 50 minutes warning. Additional sighting reports were called in by a ground observer and an aircraft, but the AIC was not in operation and had no authority to act on the information, so nothing happened.
However, what if the defenders had been alert and ready?
The Fleet
The fleet was in Condition Three. For the battleships, this specified that one-fourth of the heavy AA guns would be manned with 15 rounds of ready service ammunition on station per gun, along with two .50-caliber machine guns with 300 rounds each. The ready service ammunition was generally padlocked in ready service boxes in the immediate vicinity of each gun, with the keys under the control of the duty gunnery officer.
With a trained crew, the 5”/25 could fire up to 20 rounds per minute, so they had ready ammunition for about a minute’s fire. The ready service ammunition was to be imm
ediately supplemented by the regular ammunition supply from the main magazines. These magazines were also locked, usually with the keys in the custody of the commanding officer, the gunnery officer, or the senior duty officer. In most cases the crews did not wait but broke the locks. The ready service ammunition was fired, and then there were delays and interruptions in the ammunition supply until General Quarters was set.
Saturday offered shore leave for the officers and liberty for the sailors. With few accommodations available ashore and with personal budgets more attuned to provide drinking money than overnight room rental, most enlisted men returned to their ships after liberty, and were available Sunday morning—some with hangovers, but available. Over-night absences were mostly taken by the more senior officers and senior enlisted men, some of whom were married and had establishments ashore. Some ships had as many as 50% of their officers absent on Sunday morning. The most significant manpower gap would be in manning the gun directors, where junior officers and senior petty officers were often assigned to the AA battery directors.
The Army
