reentry vehicle. The system was initially known as WS-138A and was given the official name GAM-87 Skybolt in 1960. British involvement At the same time, the Royal Air Force (RAF) was having problems with their MRBM missile project, the Blue Streak, which was long overdue. Even if this was successful it faced the serious problem of basing. No fixed land-based missile system could be credibly installed in the British Isles; they were well within the range of Soviet air strikes. The limited land mass available meant it would be relatively easy for missile sites to be spotted no matter what security measures were taken, and flying time for a jet bomber from the coast to any potential inland location would be on the order of minutes. This left the deterrent based on their own bomber force, the V bomber fleet, which the RAF had already long concluded would be unable to penetrate Soviet defenses by about 1960. The RAF was in the process of introducing their own stand-off missile, the ranged Mach 3 Blue Steel. While capable, the missile flew at altitudes and speeds that left it vulnerable to improving SAMs, and it had a number of reliability and serviceability issues that made it less than ideal. A faster, longer-ranged version was being talked about, Blue Steel II, but it would be some time before it could enter service. The long-range Skybolt would eliminate the need for both the Blue Streak and the Blue Steel II. Blue Steel II was canceled in December 1959 and the British Cabinet decided in February 1960 to cancel Blue Streak as well. Prime Minister Macmillan met President Eisenhower in March 1960 and agreed to purchase 144 Skybolts for the RAF. By agreement, British funding for research and development was limited to that required to modify the V bombers to take the missile, but the British were allowed to fit their own warheads. In exchange, the Americans were given nuclear submarine basing facilities in Scotland. Following the agreement, the Blue Streak program was formally canceled in April 1960 and in May 1960 an agreement for an initial order of 100 Skybolts was concluded. Avro was made an associate contractor to manage the Skybolt program for the United Kingdom and four different schemes were submitted to find a platform for the missile. A number of different aircraft were considered, including a variant of the Vickers VC10