Britain is having problems keeping eight U.S. made AH-64 Apache helicopter gunships operating in Afghanistan. Britain has 67 AH-64s, and is supposed to have 144 two man crews (pilot and weapons operator). But there are only 68 crews, and the Royal Air Force has lowered the goal to 120 crews. Because of parts shortages, and cannibalizing helicopters for parts, only about a third of the AH-64s are fit for service, either in Afghanistan, or for training pilots back in Britain. Crews serve two month tours in Afghanistan, often twice a year.
The problems have been building for several years. Cuts in defense spending has led to low stockpiles of spare parts for many major weapons systems. As a result, the hard working British AH-64 helicopter gunships in Afghanistan are suffering a chronic shortage of spare parts. In reaction to this, hundreds of parts were removed from Britain's AH-64 fleet in order to keep those in Afghanistan in working order. Some British officers would like to get more AH-64s to Afghanistan, but the spare parts situation makes that inadvisable (as it would ground a large number of other AH-64s that were cannibalized.)
Britain has been cutting back on defense spending since the end of the Cold War in 1991, as have most other European countries. But operations in Iraq and Afghanistan have put more helicopters into the air, more often, and in very demanding (hot and dusty) conditions. This has used up spare parts stockpiles (which were not large to begin with), causing many helicopters to be sidelined and often cannibalized for parts, to keep others in the air.
The lack of flyable AH-64s has been a major cause of the crew shortage (machines not available for training), in addition to difficulty in recruiting suitable candidates to operate the AH-64s.