Vencer o Morir escribió:
¿Operaron los B-29 sobre europa?....

Buena pregunta.
Yo creo que no. Para la época en que entraron en acción creo que la guerra en Europa ya había terminado, no así en el Pacífico donde si fueron utilizados regularmente.
He encontrado alguna referencia en Internet que coincide con esta apreciación:
De
http://www.wpafb.af.mil/museum/air_power/ap20.htm
The Boeing B-29 was designed in 1940 as an eventual replacement for the B-17 and B-24. The first one built made its maiden flight on September 21, 1942. In December 1943 it was decided not to use the B-29 in the European Theater, thereby permitting the airplane to be sent to the Pacific area where its great range made it particularly suited for the long over-water flight required to attack the Japanese homeland from bases in China.
De
http://en.wikipedia.org/wiki/B-29_Superfortress
The initial plan was to use B-29s to attack Japan from airfields in southern China, with the main base in India, and to attack other targets in the region from China and India as needed. This was an extremely costly scheme, as there was no overland connection available between India and China, and all the supplies had to be flown over the Himalayas. The first B-29s started to arrive in India in early April, 1944. The first B-29 flight to airfields in China (over the Himalayas, or "The Hump") took place on 24 April 1944. The first B-29 combat mission was flown on 5 June 1944, with 77 out of 98 planes launched from India bombing the railroad shops in Bangkok (5 B-29s were lost to non-battle causes).
...
The need to use inconvenient bases in China for attacks against Japan ceased after the capture of the Marianas islands in 1944. On the islands of Tinian, Saipan and Guam a series of airfields were built, which became the main bases for the large B-29 raids against Japan in the final year of the war. The islands could be easily supplied by ship. The first B-29 arrived on Saipan on 12 October 1944, and the first combat mission was launched from there on 28 October 1944, with 14 B-29s attacking the Truk atoll. The first mission against Japan from bases in the Marianas was flown on 24 November 1944, with 111 B-29s sent to attack Tokyo. From that point ever more intense raids were launched regularly until the end of the war. These attacks succeeded in devastating all large Japanese cities and gravely damaging Japan's war industries.
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The B-29 was used in World War II only in the Pacific Theatre. It was later used in the Korean War, over the course of which they flew 20,000 sorties and dropped 200,000 tons (180,000 tonnes) of bombs. 3970 of the aircraft were built before they were retired in 1960.
Así que parece ser que no llegó a ser usado.