4. Acceleration ( June 28, 1945 — August 2, 1945)
From 'Ruin From The Air' by Gordon Thomas & Max Morgan Witts

Six hundred miles from Guam, at "the crossroads" — the intersection of American shipping lanes connecting the major island chains in the Pacific-submarine I.58 lay surfaced shortly before midnight, July 29.

On the bridge, peering through his binoculars, Commander Mochitsura Hashimoto saw in the moonlight a black spot on the horizon. He leaped for the ladder, shouting, "Dive!"

The bridge watch shinnied down behind him, the hatch was slammed shut, and I.58 crash-dived to thirty feet below the surface, Hashimoto's eyes glued to the night periscope fixed on the target.

It was the Indianapolis, which had delivered Furman and Nolan and their mysterious cargo safely to Tinian three days earlier. Now headed for Leyte, in the Philippines, it was likely that the Indianapolis would be ordered back to San Francisco to collect more nuclear material.

As the target came closer, Hashimoto felt a sense of excitement; this was no mere merchantman, but a large warship. Eyes pressed to the periscope, he assessed the ship's masthead height as ninety feet, too big for a destroyer. She was either a battleship or a large cruiser, steaming in a direct line toward him.

Aboard the Indianapolis, the 12:00 to 4:00 a.m. watch arrived on the bridge. One of the officers commented that visibility, which had been poor, was improving as the moon rose higher.

Earlier, the ship had followed a standard zigzag course, and her engines were phased so as to produce uneven sound patterns from her four screws, to hamper enemy submarines listening to hydro-phones. But at dusk Captain McVay had told the watch officer that the ship need not zigzag after twilight. At 10:30 p.m., with visibility still poor, MeVay had signed the night orders; they contained no orders to resume zigzagging if the weather improved. He had then retired to his cabin.

Now, at sixteen knots, the Indianapolis steamed directly toward submarine I.58. Less than ten miles of sea separated them.

At five miles, the hydrophone operators on the submarine picked up engine noises. At three miles, the target was clearly outlined in the moonlight. At two miles, Hashimoto turned to the men grouped around him and predicted, "We've got her!"

The crew waited tensely for the order to fire. The kaiten pilots began clamoring to go. Hashimoto curtly told them they would be used only if the ordinary torpedo attack failed.

With less than fifteen hundred yards separating the cruiser and submarine, Hashimoto shouted, "Stand by. Fire!"

At two-second intervals the torpedo-release switch tripped. Six torpedoes sped fanwise toward the Indianapolis.

It was two minutes past midnight, July 30, 1945.

Less than a minute later a huge column of water rose into the air, blocking out the forward turret of the U.S. warship. Another column spouted near the aft turret. As each torpedo struck home, Hashimoto gave an exultant cry. The crew of I.58 danced with joy, shouting and stamping their feet until the submarine resembled some underwater madhouse.

The cruiser was straining and already settling at the bows. Awakened by the impact, Captain McVay ordered the radio room to transmit a distress message. Moments later, without lights or power — certain indication of mortal damage — McVay gave the order to abandon ship.

The top-heavy Indianapolis rolled onto her starboard side. Her stern rose in the air, and for a few moments the glistening hull remained poised. Then, at 12: 14 a.m., barely disturbing the Pacific swell, the Indianapolis plunged out of sight — the last major vessel to be lost in World War II, and, with nearly nine hundred victims, the greatest sea disaster in the history of the U.S. Navy.

In Washington, when Groves heard of the terrible loss, he was relieved that the ship had delivered her precious cargo of uranium before being sunk. On the very day the Indianapolis was attacked, Groves had been writing a memo to the chief of staff outlining the projected production schedule for atomic bombs after August.

"In September, we should have three or four bombs ... four or three in October.... In November at least five and the rate will rise to seven in December and increase decidedly in early 1946."

Clearly, the Manhattan Project chief would have to think carefully in the future whether delivery by ship, as with the Indianapolis, was the most sensible course.

THE thirteen surviving fliers from the Taloa and the Lonesome Lady were being held prisoner within the grounds of Hiroshima Castle. They had no knowledge of the ten other U.S. servicemen who had already spent weeks in solitary confinement within the castle.

For all twenty-three Americans now in Hiroshima, life was a mixture of despair and fear. Their cells were bereft of furnishings, they had no clothes other than those they had been wearing when captured, and the three bowls of cornmeal mush or rice they received each day were barely enough to sustain them.

Occasionally they were taken to the interrogation room for bouts of hard questioning. Some invented stories, hoping to stay alive by saying what they imagined their captors wanted to hear.

One of their guards was Private Second-Class Masaru Matsuoka. He never spoke to the servicemen, but he and his fellow guards thought their dress looked so shabby that "America must be in bad shape — we can win the war yet."

Matsuoka pitied his prisoners. He could not understand why they had not killed themselves to avoid the disgrace of capture, as "we would have done." The belts and shoelaces of the prisoners had been taken away. The Japanese feared the Americans might yet commit suicide.

ON GUAM, MEANWHILE, General Spaatz, unaware of the POWs' plight, sent a top-secret message to General Handy in Washington, using the code name Centerboard for the atomic strike. It read:

HIROSHIMA ACCORDING TO PRISONER OF WAR REPORTS IS THE ONLY ONE OF FOUR TARGET CITIES FOR CENTERBOARD THAT DOES NOT HAVE ALLIED PRISONERS OF WAR CAMPS. ADVISE.

Handy spoke to Groves, then cabled a reply.

IF YOU CONSIDER YOUR INFORMATION RELIABLE HIROSHIMA SHOULD BE GIVEN FIRST PRIORITY.

Hiroshima was put at the top of the target list.

ALMOST a thousand planes, the biggest task force ever launched from the Marianas, took off four at a time from the eighty-five-hundred-foot parallel runways of Tinian's North Field on July 31 to attack a dozen Japanese cities. It took two hours for all the bombers to become airborne; by the time the last plane rose from North Field, the lead bomber was almost five hundred miles away. Yet the planes' combined payload in explosive power was less than that expected of the first atomic bomb, now assembled and resting on a cradle in one of the island's Tech Area workshops.

Tibbets, Ferebee, and Van Kirk spent the morning on Iwo Jima, six hundred miles away, checking on plans to use the island as an emergency "pit stop" for the atomic mission. If, for any reason, the plane carrying the atomic bomb developed a serious malfunction on the outward leg of its journey, it would land on Iwo; it was better to put at risk the few thousand U.S. servicemen stationed there than to endanger the more than twenty thousand on Tinian — not to mention Tinian's second priceless piece of ordnance, the plutonium weapon, which had also arrived by then.

In the center of a fenced-off area on Iwo Jima was a large open pit, precisely the same size as one in a fenced-off area on North Field, Tinian. To load the strike ship, the weapon would be lowered into the Tinian pit, and the plane wheeled into position over the hole so that the bomb could be winched up into the bomb bay. The pit on Iwo would permit quick transfer of the bomb to a standby plane if the original B-29 had to force-land on the island. A special communications center there would act as a relay station between the strike aircraft and Tinian.

The next morning, at the 509th's headquarters, after one of Mess officer Perry's magnificent breakfasts, Tibbets adjourned to his office, closed the door, sat at his desk, and wrote rapidly. It took him only minutes to draft the top-secret order LeMay would write for the first atomic attack in history. He sealed the draft in an envelope and sent it by special courier to LeMay's headquarters on Guam.

The order specified that a total of seven B-29s would be used on the historic mission. One would be needed at Iwo Jima as the standby aircraft. Three would be weather planes, flying well ahead of the strike ship, one to each of the potential target cities to appraise the local weather and relay information back to the bomb carrier. The strike ship would be accompanied by two observer planes.

At noon Tibbets sent for his intelligence officer, Lieutenant Colonel Hazen Payette, and the intelligence officer of the original 393rd Squadron, Captain Joseph Buscher, who on that first day at Wendover had urged the fliers to "give the place a chance."

Tibbets told the two men about the impending mission and ordered them to be ready to brief the selected crews on what the target cities looked like from thirty thousand feet.

Then Tibbets spoke to Mess Officer Perry, and to Charles Sweeney of crew No. 15, whose plane had been named The Great Artiste in honor of its highly efficient bombardier, Captain Kermit Beahan. Tibbets ordered Perry to make sure he had "a goodly supply of pineapple fritters ready from August 3 onward." The fritters were Tibbets' favorite meal; he liked several helpings before he flew.

Tibbets then briefed Sweeney on the forthcoming mission. He told the Boston Irishman that The Great Artiste would be turned into a flying laboratory, carrying sensitive instruments to measure the blast and other effects of the bomb. Sweeney's, and a second B-29 carrying photographic equipment, would be the two observer planes accompanying Tibbets' No. 82 to the target.

The following day, August 2, Tibbets told Van Kirk that he would be the navigator on the bomb carrier. Tibbets did not send for Bob Lewis to tell him that he would be his copilot. He felt that was "so self-evident it didn't warrant stating."

That afternoon Tibbets and Ferebee arrived at LeMay's headquarters on Guam to complete the details Tibbets had been unable to incorporate in his draft of the mission order.

The first thing the two fliers needed to know was which target city LeMay personally preferred. Because Hiroshima contained a large number of troops and war factories, LeMay was happy with it. He turned to Tibbets and said, almost casually, "Paul, the primary's Hiroshima."

Tibbets' response was immediate. "I've always preferred it."

LeMay then led his visitors to a large map table covered with the latest reconnaissance photographs of Hiroshima. As Tibbets and Ferebee studied them, LeMay called in Operations Officer Blanchard.

"Bombing from the height you intend," LeMay said to Tibbets and Ferebee, "crosswinds can be a big problem."

Ferebee agreed, saying his bombsight

"could handle twenty-five to thirty degrees of crosswind, but it sometimes gets to forty to fifty degrees up there."

Blanchard proposed a solution.

"You should fly directly down-wind. That would have the double advantage of increasing your speed, so you wouldn't be vulnerable over the target so long, and you wouldn't have to worry so much about crosswinds."

Tibbets disagreed. He thought it better to head directly into the wind, which could eliminate crosswind effect and give Ferebee the best chance to bomb accurately.

LeMay stated that going against the wind would reduce the aircraft speed, making the journey over the target more hazardous. Ferebee looked at Tibbets and then spoke for them both.

"Our primary purpose is to hit the target. We're going up there to bomb, not to play safe."

"Okay, the heading will be into the wind." LeMay then asked Ferebee to select his aiming point.

The bombardier unhesitatingly placed his index finger on the T-shaped Aioi Bridge, in the center of Hiroshima. LeMay nodded.

Tibbets agreed. "It's the most perfect AP I've seen in this whole damn war."