Tinian

In July 1944, US marines and army had captured Saipan as the first sub-goal in operation Forager (capturing Northern Mariana Islands). The next sub-goal of the operation was Tinian, located only about five kilometers south of Saipan. Like Saipan, there were airfields that americans could use for raids on the Japanese mainland and its islands. The Japanese themselves had used Tinian as a base for airstrikes on the US navy. The Japanese defense on Tinian was not as extensive as on Saipan. Tinian was also quite flat and more difficult to build up an effective defense. The number of defenders amounted about 6,000 men and was a mixture of army, air force and fleet. Those who belonged to the army were under the command of Colonel Kiyochi Ogata. Vice Admiral Kakuji Kakuta commanded those who belonged to the fleet. Captain Goici Oie commanded the crew stationed at one of the three airfields on Tinian. Kakuta was the one who had the highest rank but it was Ogata who became responsible for the defense on Tinian.

The americans discussed suitable beaches for an amphibious operation and the choice fell on two small beaches on the northwest side of the island. They were named White 1 and White 2. The Japanese had expected a landing further south and it was there the emphasis of their defence had been laid. On July 24th, the american 2nd and 4th marine division begun the amphibious operation on Tinian. As expected, the resistance was weak, although sporadic battles occured. As in Saipan, the operation on Tinian had been preceded by an intense bombardment to weaken the Japanese defence. The Marines could therefore quite unimpeded bring both materials and men ashore for further advance south. Despite Japanese counter-attacks, the marines could effectively wipe out the Japanese defense on the island. After a week Tinian was secured and captured. Marine General Holland Smith said that the invasion of Tinian was ”the most perfect amphibious operation in the Pacific”. Tinian was also the first battle in which americans used napalm in an attempt to destroy the sugar fields where Japanese soldiers could hide.

Japanese losses in the battle amounted about 5,500, many of them chosed suicide instead of the disgrace ending up in captivity. All three commanders committed suicide. Just as in Saipan, Japanese soldiers fought furiously, and only about 500 were captured. Some Japanese soldiers remained hidden in caves until the end of the war, some longer than that. Of the approximately 16,000 Marines who took part in the operation, only about 300 were killed and about 1,500 were wounded. Just as on Saipan, hundreds of Japanese (civilians and soldiers) chose to commit suicide by jumping out of a steep precipice on southern Tinian and were killed when crashing into the cliffs and the sea below.

At Tinian there were three airfields that the Japanese had built and two of these american engineering troops begun to expand. They were named North Field and West Field. The largest was North Field, which when completed in February 1945 consisted of four runways about 2.5 kilometers long each. The runways were from north to south named A (Able), B (Baker), C (Charlie) and D (Dog/Delta). In connection with these, a number of buildings with various functions were built, such as barracks, mess halls, officer clubs, dining rooms, kitchens, chapels, theatres, conferences, administration buildings. The whole island became like a small town where everything revolved around the airfields, especially North Field.

The airfields were put under the USAF XXI Bomber Command which stationed the 313th Bombardment Wing on Tinian. The 313th, with its B-29 Superfortress, conducted regular raids against Japanese targets in the Philippines, Okinawa, Iwo Jima and the japanese mainland. Bombers that took part in the massive raid on Tokyo on March 9 and 10, 1945, took off from Tinian. A raid that resulted in about 100,000 dead and one million homeless. In 1945 and until the end of the war in September, 1945, Tinian and North Field were the largest and busiest airfield in the world. In total there were 265 B-29 stationed at Tinian.

In May 1945, the 509th Composite Group was stationed at Tinian and placed in the southwestern part of the North Field. Their mission was to carry out special missions against Japanese targets and was surrounded by secrecy and was partially cut off from the rest of the base. In early August, 1945, it becmae clear what special mission 509th Composite Group had. Early in the morning of August 6, 1945, the B-29, Enola Gay, with a crew of twelve, under the command of Colonel Paul W. Tibbets, took off from runway A (Able) to Hiroshima in southern Japan. About six hours later, they arrived at the target and dropped the first atomic bomb in history. The bomb was called Little Boy and was the final result of the american Manhattan project that had been going on since 1942 with the purpose off produce an atomic bomb. 

Uranium and other components for Little Boy had been secretly transported to Tinian at the end of July by the cruiser USS Indianapolis. At Tinian, it was then mounted under equal secrecy and through a special-built pit (Atomic Bomb Pit no. 1) with hydraulic lift been loaded on Enola Gay hours before the mission. Little Boy weighed about four tons and was equipped with 60 kg of uranium that gave an explosive power of about 15 tons of trotyl. The bomb detonated to achieve maximum effect at an altitude of about 600 meters. It destroyed everything within a radius of about 1.6 kilometers and killed about 100,000 people directly or in the following days and weeks. After completing the mission, Enola Gay returned to Tinian without mishaps. The whole mission took about twelve hours. The hope from the americans was that the bomb would make the Japanese realize the futility of continuing the war and surrender.

But the Japanese had no plans to surrender and therefore the americans decided to drop a second atomic bomb. Early in the morning of August 9, Bockscar (also a B-29) took off with the second atomic bomb in history from runway A (Able). This bomb had been loaded on Bockscar from the second pit (Atomic Bomb Pit no. 2). Captain was Major Charles W. Sweeney and the destination was Kokura in southern Japan. However, the weather over Kokura was cloudy and visibility poor and Sweeney therefore decided to continue towards the secondary goal, Nagasaki. It was cloudy over Nagasaki as well but a gap in the cloud opened upp the possibility to drop the second atomic bomb just after 11.00 am. This atomic bomb was called Fat Man and detonated at an altitude of about 500 meters to achieve maximum effect. Fat Man weighed about 4.5 tons and was equipped with about six kilograms of plutonium that gave an explosive power equivalent to about 21 tons of trotyl and destroyed everything within a radius of 1.6 kilometers. Components for Fat Man had been delivered to Tinian at the end of July and were assembled under the utmost secrecy before being loaded on Bockscar. The idea was actually that the assignment would be carried out on August 11th, but the weather forecast did not look promising and therefore the assignment was brought forward.

Fat Man killed between 40,000 – 75,000 immediately or in the following days and weeks. Fat Man probably would have killed more people if it had been dropped at the intended site. The visibility conditions were not the best, which made it difficult to locate the site and instead it was dropped about 2.5 kilometers away from the planned drop point. This caused the blast radius to be smaller because the bomb detonated in a place surrounded by mountains. Bockscar could not return to Tinian because she had problems with the fuel system. Instead, Bockscar landed on Okinawa with more or less empty fuel tanks. A third bomb was also planned to be dropped, but since Japan surrendered on August 15, it was never materialized.