The significance of the sinking of U-487 was far greater than just the loss of a refueler, as critical as that may have been. The loss of this U-tanker affected a whole operation in the East. After the U-boats were no longer being used to great extent on the North Atlantic convoy route, one of the remaining areas where they could be most useful was the Indian Ocean and Persian Gulf areas. A base in the Far East was a necessity. Such a base was negotiated with the Japanese and the first U- boat arrived at Penang, Malaysia in July of 1943. The establishment of the supply base at Penang helped bring to fruition a scheme that had been considered for some time. This was the use of U-boats as cargo carriers. Germany's shortage of rubber, tin, tungsten, and molybdenum had forced the Germans to blockade run with surface vessels in order to maintain supplies of these necessary materials. The surface blockade runners were suffering a severe loss rate, however, and this made it clear that another more secure means must be found to transport supplies. This solution involved transport submarines. With the base at Penang needing supplies and Germany needing raw materials, the idea was to carry out a round trip carrying cargo both ways. Some of the boats used in this venture that actually spanned from June 1943 to March 1944 were operational U-boats. During 1943 the most commonly used was the 750-ton IX-C boat. These U-boats could carry about 110 tons of cargo and also operate enroute if they were refuelled. These were the so-called Monsun boats. During the summer of 1943, 11 Monsun boats left France for the Far East. By the end of August, five had been sunk in mid-Atlantic and one had been forced to return to port. This disaster for the Germans was largely attributable to the sinking of U-487, a 1600-ton refueler, on 13 July. This was the U-boat that was to have refuelled the Monsun boats. The rendezvous area had four US Navy carriers in the vicinity. They were Core, Santee, Bogue, and Card. On the afternoon of 13 July, one of Core's Wildcat-Avenger teams spotted U-487 on the surface. The crew was pulling a floating bale of cotton aboard and were caught totally by surprise. They reacted quickly, however, and shot down the Wildcat. Three other aircraft arrived immediately on the scene and the U-487 was bombed and sunk quickly. Ultra played a role in this sinking to the extent that bits and pieces of information were put together. First, through Ultra it was known that the area SSW of the Azores was a favourite refuelling area. Second, it was known that several U-boats were being sent out from France and thought to be headed for the Far East. Third, it was known that U-487, which was a known U-tanker, had been given instructions to head for that general area. Thus, even though traffic was not at the time being read currently, past Ultra information was instrumental in revealing that a large refuelling operation was about to take place.
Please forgive my ignorance Jim, but what was/is 'Ultra':red: edit: Oops, Ultra being the information gleaned from Enigma codes:red:
Breaking the Enigma signals and the distribution of the resulting intelligence was codenamed Ultra. I guess you sort of answered this youself Kelly.
