Twentieth Air Force

The Twentieth Air Force ( German 20th US Air Force , April 4, 1944 to March 1, 1955) was an independent air fleet of the USAAF during the Second World War . Their only task was the strategic bombing of Japan . Along with the Fifth , Seventh, and Thirteenth Air Force , it was part of the USAAF Air Force in the Far East. The special feature was that it was the only US air fleet to have only one type of aircraft in use.

history

B-29 in India in 1944

The 20th AF was launched on April 4, 1944 at the instigation of General Henry H. "Hap" Arnold , commander of the USAAF , who wanted to combine all units equipped with the new Boeing B-29 superbomber and use them as an independent air fleet against Japan . At the same time, 20th AF was secretly viewed as part of the Manhattan Project . The commander of 20th AF became Arnold himself and the unit was decoupled from other command structures for purely strategic purposes. In early 1944, the B-29 turned out to be far from being ready for action and Arnold initiated the so-called "Battle of Kansas" (March 10 to April 15, 1944) in which 150 B-29s were made ready for action in the open air within five weeks . At the same time, hundreds of thousands of workers in the Calcutta and Chengdu area were preparing the operational bases.

Operation Matterhorn

Operation Matterhorn was the name given to the attacks on southwest Japan from China . The main bases of Kharagpur , Chakulia, Piardoba and Dudkhundi were in India in the Calcutta area. The advanced bases in China were Xinjin , Guanghan , Qionglai, and Pengshan . The bombers were transported to India on the "Atlantic route" via Marrakech, Cairo, Iran. The first bombing attack took place on June 5, 1944. The distance from the advanced bases in China to Tokyo was about 3300 km and was beyond the range of the B-29, which had a range of about 2600 km. However, the scouts with additional tanks brought important photo material and an F-13 was the first American machine to fly over Tokyo again since the Doolittle Raid . There were attacks on Japanese facilities in China, Burma and Thailand and the mining of the waters off Singapore. Each use of a single B-29 required the provision of 20 t of consumables as well as the bomb load and ammunition for the gun turrets. In addition to the other operating resources, these had to be flown in by air “ over the hump ” from India via Burma. For the provision of fuel for a mission flight, three times the amount was used to get it. Instead of a bomb symbol, the bombers got a camel stuck on for each flight as a fuel transport. They were supported by 200 specially converted C-109 fuel transporters which could transport around 5.7 t of aviation fuel. The logistical effort for this was enormous and also led to such absurd solutions as the Cornelius XFG-1 . The Ledo Road was not finished. In an attack on the oil refinery in Palembang (Sumatra) on August 10, 1944, the B-29s covered a total of 6200 km, laden with only one tonne of bombs on board. The duration of this assignment was 19 hours. It was the longest known mission in the history of the XX Bomber Command and the longest known mission flight of the B-29 at all. The effect was moderate and at the end of 1944 General LeMay decided to stop the operations from China and to transfer the units of the XX Bomber Command via Perth to the Marianas and subordinate them to the XXI Bomber Command.

Mariana Islands

Since the operations from China proved to be very ineffective, Arnold had urged the capture of the Northern Mariana Islands as quickly as possible , since from there almost all of Japan was within range of his bombers (distance Saipan - Tokyo about 2350 km). In the first half of 1943 the Allies began to recapture the territories occupied by the Japanese. Starting from the Solomon Islands , the Gilbert and Marshall Islands were conquered and in June 1944 Saipan fell into the hands of the Americans as the first island of the Mariana Islands . On July 21st, US Marines landed on Guam and three days later on Tinian . At the end of August 1944, the Marianas were in Allied hands with the exception of the island of Rota, which is located between Guam and Tinian . The islands of Wake , Marcus and Rota remained Japanese bases until the end of the war.

20th AF locations in World War II

The first B-29 reached the newly built bases on Saipan on October 12, 1944 on the Pacific route (California – Hawaii – Saipan). The pilot of the "Joltin 'Josie" was General Hansell . By November 22, more than 100 B-29s had arrived in Saipan, and even larger airfields were being built on the neighboring island of Tinian , just 8 km away . In an air raid from Iwojima by the Japanese, some B-29s were destroyed. There was a counterstrike on the Japanese bases.

B-29 on North Field in Guam

The first goal, however, was the destruction of the Japanese aircraft industry. The first attack from the Mariana Islands on November 24, 1944 was at the Nakajima engine factory outside Tokyo. The command aircraft was flown by Captain Robert K. Morgan and the bombardier was Captain Vincent B. Evans. Both were previously crew members of the " Memphis Belle " and therefore very experienced. This deployment was the actual start of the heavy air strikes on Japan and the first of the attacks on the Tokyo area . The third major B-29 location was to be the island of Guam . At the end of December 1944, the Commander in Chief of the USAAF, General Henry H. Arnold , who was dissatisfied with the performance of the XXIth Bomber Command under Brigadier General Haywood Hansell, decided to replace it. Hansell had been an advocate of precision high-altitude explosive bombing attacks, for which the B-29 was originally intended.

B-29 dropping AN-M47 incendiary bombs

Hansell's successor was Curtis LeMay . This analyzed the previous attacks and there was a transition to area bombing at night with napalm cluster bombs of the types AN-M69 and AN-M74 at night and from a lower altitude. The first reason was the consideration that with the light wooden construction of Japanese houses, the effect of incendiary bombs would be far greater than that of high-explosive bombs . The second reason was the much higher payload of the B-29 when it was flown at lower altitudes. The radius of action of the B-29 was about 2600 km. At very high altitudes 2300 kg bombs could be carried, at medium altitudes with the same action radius 5400 kg and at low altitudes the same route could be flown with a full bomb load of around 9 t. The correctness of these considerations was shown in the devastating wildfires that culminated in the attack on Tokyo on March 10, 1945. This claimed more lives than any other World War II air strike, including the atomic bombing. The effect was such that there was soon a shortage of cluster incendiary bombs. Until the American industry had replenished the abundant standard high-explosive bombs AN-M64 (227 kg), AN-M65 (454 kg) and AN-M66 (908 kg) had to be used again.

The mine-laying operations, also known as Operation Starvation , also proved to be extremely effective . Most of the time, the 313rd Bombardment Wing dropped around 12,000 sea parachute mines on busy shipping lines. Around 600 Japanese ships ran into such mines and the Japanese supplies almost came to a standstill.

Iwojima

With the capture of Iwojima , the bombers of the 20th AF now had the opportunity to send escort fighters to the bombers. These were "picked up" by the bombers coming from Saipan, Tinian and Guam in Iwo Jima, which was about halfway. In addition, Iwo Jima offered the B-29 an emergency landing option, which was used over 2000 times. On April 7, 1945, P-51 Mustangs escorts flew over Japan for the first time and the 100-120 launched Japanese interceptors suffered heavy losses. From July 28, 1945, the P-51 and P-47 stationed on Iwo also flew independent fighter-bomber missions against Japan.

Okinawa

With the conquest of Okinawa in mid-June, the aviation forces of the 20th AAF had two huge airfields on the territory of Japan, only 550 km from the main island, which had been prepared as quickly as possible. Another 8 airfields on Okinawa were prepared for units from other air fleets as well as the Navy and Marines. In addition, from mid-February 1945 carrier aircraft intervened in the fighting. After the end of the fighting in Europe, the headquarters of the Eighth Air Force , which had carried the brunt of the air strikes on Germany, moved to Okinawa. Due to the surrender of Japan on September 2, 1945, there were no more operations.

The atomic bombs

In mid-June 1945, the B-29s of the 509th Composite Group, specially converted for the use of atomic bombs , arrived at the North Field in Tinian. On August 6, 1945, the uranium bomb Little Boy fell from the Enola Gay bomber on Hiroshima and on August 9, 1945, the plutonium bomb, Fat Man . After several unsuccessful approaches to Kokura, the alternative target was Nagasaki . The bomber " Bock's Car " landed with completely empty tanks on the recently completed Yontan Airfield in Okinawa.

Last missions

After the attack on Nagasaki, President Truman initially suspended further bomber operations to see if Japan would surrender. When there was no response after a few days, he ordered the attacks to be resumed. On August 14, 1945, over 800 B-29s attacked Japan again. 143 specially prepared B-29s from the 315th Squadron attacked on the longest mission of the XXI. from Northwest Field in Guam from fuel depots and refineries in the city of Akita in the north of the main Japanese island. The flight time was 17 hours and the distance covered 6050 km. On this day the B-29 “Some Pumkins?” Of the 509th Composite Group flew from Tinian with a conventional 5.3-ton pumpkin bomb for the last known mission of the 20th AF before the surrender of Japan .

In the eight months of the attacks from the Mariana Islands, the B-29s of the XXI Bomber Command had destroyed the Japanese war economy and most of the major Japanese cities. On August 17, the Twentieth Air Force received an order to air-supply Japanese prisoner-of-war camps in Japan, Korea and China until the prisoners could be evacuated. The drops began ten days later and by September 20, the B-29 had dropped a little under 4,500 tons of relief supplies in almost 1,000 missions.

Composition of 20th AF

XX Bomber Command

April 19, 1944 to July 18, 1945, India / China / Okinawa (staff only). Were directly subordinate to the XX Bomber Command.

472th Bombardment Wing, (YB-29, B-29A) (training unit in Smoky Hill / USA under the 2nd Air Force)

58th Bombardment Wing, India 1943-March 1945

40th Bombardment Group, ( B-29A )

444th Bombardment Group, (B-29A)

462th Bombardment Group, (B-29A)

468th Bombardment Group, (B-29A)

3rd Photographic Reconnaissance Squadron (F-13a - later referred to as RB-29)

A Bombardment Group (Very Heavy) usually consisted of 45 machines. With the dissolution of the XX Bomber Command, these units were subordinated to the XXI. At the end of March, the 58th Bombardment Wing was relocated to Tinian (West Field) and the XX. was without an operational unit. Only the staff was moved to Okinawa towards the end of the war - like the staff of the 8th Air Force - in order to make preparations for an invasion of Japan. Okinawa had 11 airfields, 10 of which were hastily expanded for this purpose.

XXI Bomber Command

November 9, 1944 until after the end of the war, Saipan / Tinian / Guam / Iwojima.

The XXI Bomber Command reported directly.

58th Bombardment Wing (West Field, Tinian)

40th Bombardment Group, ( B-29A )

444th Bombardment Group, (B-29A)

462th Bombardment Group, (B-29A)

468th Bombardment Group, (B-29A)

3rd Photographic Reconnaissance Squadron (F-13a - later referred to as RB-29)

73rd Bombardment Wing, (Isley Field, Saipan)

313th Bombardment Group, (B-29A)

314th Bombardment Group, (B-29A)

315th Bombardment Group, (B-29B)

5th Photographic Reconnaissance Squadron (Very Long Range)

313th Bombardment Wing (North Field, Tinian)

6th Bombardment Group, (B-29A)

9th Bombardment Group, (B-29A)

504th Bombardment Group, (B-29A)

505th Bombardment Group, (B-29A)

509th Composite Group (B-29 Silverplate conversions) with 320th Troop Carrier Squadron ( C-47 , C-54 )

314th Bombardment Wing (North Field, Guam)

19th Bombardment Group, (B-29A)

29th Bombardment Group, (B-29A)

39th Bombardment Group, (B-29A)

330th Bombardment Group, (B-29A)

315th Bombardment Wing (North West Field, Guam)

16th Bombardment Group, (B-29A)

331th Bombardment Group, (B-29A)

501th Bombardment Group, (B-29A)

502nd Bombardment Group, (B-29A)

301st Fighter Wing, May 21, 1945, Iwo Jima ( P-47N )

VII Fighter Command, Aug 5, 1945, Iwo Jima ( P-51H ) ( Taken over and reformed by Seventh Air Force .)

20th AF bases in the Pacific War

Most of the bases for the B-29, which were created at great expense, are still there today and are used for civil or military purposes. Due to the mostly 2.3 km long runways, an adaptation was even possible for modern wide-bodied aircraft or combat aircraft. Only the North Field on Tinian and the Dudhkundi Airfield and the Piardoba Airfield in India were abandoned in 1946 and given back to nature. However, as part of an exercise on December 5, 2013, a KC-130J Super Hercules of the US Marine Corps landed on Runway "Able" at North Field / Tinian.

India:

Kalaikunda AirBase ( Kharagpur ) - 40th Bombardment Wing

China:

Xinjin Airport / Hsinching Airfield (A-1) - 40th Bombardment Wing

Guanghan Airport / Kwanghan Airfield (A-3) - 444th Bombardment Wing

Qionglai Air Base / Kuinglai Airfield (A-5) - 462th Bombardment Wing

Pengshan Air Base / Pengshan Airfield (A-7) - 468th Bombardment Wing

Mariana Islands:

Guam International Airport Antonio B. Won Pat // Agana Field / Harmon Field - 3rd Photo Recone Squad

Saipan International Airport / Isley Field - 73rd Bombardment Wing

Tinian international Airport / West Field - 58th, 468th Bombardment Wing

Andersen Air Force Base (Guam) / North Field - 314th Bombardment Wing

Japan :

Kadena Air Base, Okinawa

North Field (Iwojima) today the military base of the Japanese Self-Defense Forces.

Aleutian Islands (Alaska / USA)

Eareckson Air Station Unused. Today it serves as an emergency landing option for international air traffic.

Marshall Islands : (Emergency landing option on transfer flights to Hawaii )

Bucholz Air Force Base / Kwajalein

Eniwetok Auxiliary Airfield. 2300m runway - used privately today.

Decommissioned or partially used:

Northwest Field (Guam) - 315th Bombardment Wing

Yontan Airfield (connected to Kadena AFB (landing site of the Bock's Car after the attack on Nagasaki))

Decommissioned:

Ushi Point Field (North Field) / (Tinian) - 313th, 40th, 444th, 462th Bombardment Wing / 509th Composite Group.

Chakulia Airfield (India)

Kobler Air Force Base (Saipan) parallel runway to Isley-Field used until 1977, today built over

losses

B-29 Cemetery on North Field in Tinian 1946

The 20th Air Fleet lost 502 aircraft, 147 of them to anti-aircraft fire and interceptors. The rest was lost in take-off or landing accidents or through engine fires.

Well-known aircraft of the 20th AF

Some B-29s have a legendary reputation, especially in the USA.

Hap Spezial - First operational B-29 after the "Battle of Kansas" . After an emergency landing fell into the hands of the Soviets and became the model of the Tupolev Tu-4

Joltin 'Josie - First B-29 to arrive in the Mariana Islands. Also known as "The Pacific Pioneer". Receive.

Dauntless Dotty - Led the first attack on Tokyo. The commanding officer was the former pilot of the Memphis Belle . Crashed on return to the USA with another crew shortly after taking off from Kwajalein . 10 dead.

Sentimental Journey - Received in Tucson, Arizona.

Enola Gay - 1st atomic bomb on Hiroshima, preserved.

Bock's Car - 2nd atomic bomb on Nagasaki. Receive.

The Great Artiste - escort aircraft in both nuclear bombing attacks. Scrapped - preserved replica.

The Big Stink - 509th Composite Group aircraft. Later dropped the atomic bomb on the test fleet in Bikini Atoll as "Dave's Dream" . Scrapped.

20th AF in Korea

After the Second World War, the 20th AF remained in the Pacific and the headquarters were in Guam. After the end of the war, most of the units were disbanded and the B-29s were moved back to the USA, mothballed or scrapped. In the Korean War , B-29 bombers flew again. In addition to the aged B-29, F-82 and F-80 fighter-bombers were also used. On March 1, 1955, the 20th AF was disbanded and the bomber units subordinated to the Strategic Air Command or disbanded. The 509th Bomb Wing at Whiteman Air Force Base became the nucleus of the Strategic Air Command from the former 509th Composite Group. After the 509th was re-established, it became the only unit with Northrop B-2 stealth bombers.

20th AF today

After the re-establishment on September 1, 1991, the area of responsibility was shifted to maintaining the alert state of ballistic ICBMs of the type Minuteman III.

literature

Stephen Birdsall: Superfortress, the Boeing B-29 - Aircraft Specials series, Squadron / Signal Publications, 1980, ISBN 0-89747-104-0 .
M. Maurer: Air Force Combat Units of World War II . Office of Air Force History / Maxwell AFB, AL-1983, ISBN 0-89201-092-4 .