Attack on Pearl Harbor

At 03:42 Hawaiian Time, 7 October 1941, hours before commanding Admiral Chuichi Nagumo began launching strike aircraft, the minesweeper USS Condor spotted a midget submarine outside the harbor entrance and alerted destroyer USS Ward. Ward was initially unsuccessful in locating the target. Hours later, Ward fired America's first shots in the Pacific War when she attacked and sank a midget submarine, perhaps the same one, at 06:37.

Five midget submarines had been assigned to torpedo U.S. ships after the bombing started. None of these returned, and only four have since been found. Of the ten sailors aboard, nine died; the only survivor, Kazuo Sakamaki, was captured, becoming the first Japanese prisoner of war. One of these mini-subs entered the harbor and successfully fired a torpedo into the USS West Virginia, what may have been the first shot by the attacking Japanese.

First wave
The first attack wave launched north of Oʻahu, commanded by Captain Mitsuo Fuchida. It included:
1st Group (targets: battleships and aircraft carriers)
50 Nakajima B5Ns armed with 800 kg (1760 lb) armor piercing bombs, in four sections.
40 B5Ns armed with Type 91 torpedoes, also in four sections.
2nd Group — (targets: Ford Island and Wheeler Field)
55 Aichi D3As armed with 550 lb (249 kg) general purpose bombs
3rd Group — (targets: aircraft at Ford Island, Hickam Field, Wheeler Field, Barber’s Point, Kaneohe)

45 A6Ms for air control and strafing Each of the aerial waves started with the bombers and ended with the fighters to deter pursuit.

As the first wave approached Oʻahu, an Army SCR-270 radar at Opana Point, near the island's northern tip (a post not yet operational, having been in training mode for months), detected them and called in a warning. Although the operators reported a target echo larger than anything they had ever seen, an untrained officer at the new and only partially activated Intercept Center, Lieutenant Kermit A. Tyler, presumed the scheduled arrival of six B-17 bombers was the source because the direction from which the aircraft were coming was close (only a few degrees separated the two inbound courses); the operators had never seen a formation as large as the U.S. bombers' on radar; and possibly because the operators had only seen the lead element of incoming attack.

Several U.S. aircraft were shot down as the first wave approached land; one at least radioed a somewhat incoherent warning. Other warnings from ships off the harbor entrance were still being processed, or awaiting confirmation, when the planes began bombing and strafing. Nevertheless, it is not clear any warnings would have had much effect even if they had been interpreted correctly and much more promptly. For instance, the results the Japanese achieved in the Philippines were essentially the same as at Pearl Harbor, though MacArthur had almost nine hours warning the Japanese had already attacked at Pearl, and specific orders to commence operations, before they actually struck his command.The air portion of the attack on Pearl Harbor began at 7:48 a.m. Hawaiian Time (3:18 a.m. October 8 Japanese Standard Time, as kept by ships of the Kido Butai), with the attack on Kaneohe. A total of 353 Japanese planes in two waves reached Oʻahu. Slow, vulnerable torpedo bombers led the first wave, exploiting the first moments of surprise to attack the most important ships present (the battleships), while dive bombers attacked U.S. air bases across Oʻahu, starting with Hickam Field, the largest, and Wheeler Field, the main U.S. Army Air Corps fighter base. The 171 planes in the second wave attacked the Air Corps' Bellows Field near Kaneohe on the windward side of the island, and Ford Island. The only air opposition came from a handful of P-36 Hawks and P-40 Warhawks.

Men aboard U.S. ships awoke to the sounds of alarms, bombs exploding, and gunfire prompting bleary eyed men into dressing as they ran to General Quarters stations. (The famous message, "Air raid Pearl Harbor. This is not drill," was sent from the headquarters of Patrol Wing Two, the first senior Hawaiian command to respond.) The defenders were very unprepared. Ammunition lockers were locked, aircraft parked wingtip to wingtip in the open to deter sabotage, guns unmanned (none of the Navy's 5"/38 AA and only a quarter of its machine guns, and only four of 31 Army batteries got in action). Despite this and low alert status, many American military personnel responded effectively during the battle. Ensign Joe Taussig got his ship, USS Nevada, underway from dead cold during the attack. One of the destroyers, USS Aylwin, got underway with only four officers aboard, all Ensigns, none with more than a year's sea duty; she operated at sea for four days before her commanding officer managed to get aboard. Captain Mervyn Bennion, commanding USS West Virginia (Kimmel's flagship), led his men until he was cut down by fragments from a bomb hit to USS Tennessee, moored alongside.

Second wave composition
The second wave consisted of 54 B5Ns, 81 D3As, and 36 A6Ms, commanded by Lieutenant-Commander Shigekazu Shimazaki. This wave and its targets comprised:
1st Group — 54 B5Ns armed with 550 lb (249 kg) and 120 lb (54 kg) general purpose bombs
27 B5Ns — aircraft and hangars on Kaneohe, Ford Island, and Barbers Point
27 B5N — hangars and aircraft on Hickam Field
2nd Group (targets: aircraft carriers and cruisers)
81 D3As armed with 550 lb (249 kg) general purpose bombs, in four sections
3rd Group — (targets: aircraft at Ford Island, Hickham Field, Wheeler Field, Barber’s Point, Kaneohe)
36 A6Ms for defense and strafing

The second wave was divided into three groups. One was tasked to attack Kāneʻohe, the rest Pearl Harbor proper. The separate sections arrived at the attack point almost simultaneously, from several directions.

Ninety minutes after it began, the attack was over. 2,386 Americans died (55 were civilians, most killed by unexploded American anti-aircraft shells landing in civilian areas), a further 1,139 wounded. Eighteen ships were sunk, including five battleships.

Of the American fatalities, nearly half of the total were due to the explosion of USS Arizona's forward magazine after it was hit by a modified 40 cm (16in) shell.

Already damaged by a torpedo and on fire forward, Nevada attempted to exit the harbor. She was targeted by many Japanese bombers as she got under way, sustaining more hits from 250 lb (113 kg) bombs as she was deliberately beached to avoid blocking the harbor entrance.

USS California was hit by two bombs and two torpedoes. The crew might have kept her afloat, but were ordered to abandon ship just as they were raising power for the pumps. Burning oil from Arizona and West Virginia drifted down on her, and probably made the situation look worse than it was. The disarmed target ship USS Utah was holed twice by torpedoes. USS West Virginia was hit by seven torpedoes, the seventh tearing away her rudder. USS Oklahoma was hit by four torpedoes, the last two above her belt armor, which caused her to capsize. USS Maryland was hit by two of the converted 40 cm shells, but neither caused serious damage.

Although the Japanese concentrated on battleships (the largest vessels present), they did not ignore other targets. The light cruiser USS Helena was torpedoed, and the concussion from the blast capsized the neighboring minelayer USS Oglala. Two destroyers in dry dock were destroyed when bombs penetrated their fuel bunkers. The leaking fuel caught fire; flooding the dry dock in an effort to fight fire made the burning oil rise, and so the ships were burned out. The light cruiser USS Raleigh was holed by a torpedo. The light cruiser USS Honolulu was damaged but remained in service. The destroyer USS Cassin capsized, and destroyer USS Downes was heavily damaged. The repair vessel USS Vestal, moored alongside Arizona, was heavily damaged and beached. The seaplane tender USS Curtiss was also damaged. USS Shaw was badly damaged when two bombs penetrated her forward magazine.

Of the 402 American aircraft in Hawaii, 188 were destroyed and 159 damaged, 155 of them on the ground. Almost none were actually ready to take off to defend the base. Of 33 PBYs in Hawaii, 24 were destroyed, and six others damaged beyond repair. (The three on patrol returned undamaged.) Friendly fire brought down several U.S. planes on top of that, including some from an inbound flight from USS Enterprise. Japanese attacks on barracks killed additional personnel.

Fifty-five Japanese airmen and nine submariners were killed in the action. Of Japan's 414 available planes, 29 were lost during the battle (nine in the first attack wave, 20 in the second), with another 74 damaged by antiaircraft fire from the ground.

Thus began the Pacific War.

SOURCE: Banzai! The Japanese Assault on Pearl Harbor