Half the Royal Navy's helicopters are out of action because of lack of money for spares and maintenance, according to figures obtained by The Herald.
In addition, ground attack jet squadrons' Harriers and Jaguars were cannibalised for spare parts to keep others flying on 930 occasions in 2005.
Of 122 Sea King, Merlin, and Lynx helicopters in the RN's order of battle, 61 were "unfit for purpose" last week.
The MoD said aircraft were judged to be "in service" only when they were "available, reliable, airworthy, and capable of carrying out their missions
on given dates".
A spokesman said that the numbers "fit for service" could vary widely, depending on operational requirements. In an emergency, more would be made operational.
On the Harrier GR7 and Jaguar jets, he added: "The removal of spare parts from one aircraft for use on another is a short-term, temporary measure to
ensure that the maximum number of aircraft are available to the front line."
The figures, revealed in written parliamentary answers, come a year after the Commons public accounts committee warned that the gap between the number of helicopters needed and those available was 20% to 38%.
The MPs said the shortages, though "alarming" had not affected front line capability, but were having an impact on training pilots and crews.
The helicopter shortfall has been worsened by the £259m purchase of eight Chinook Mark 3 heavy-lift aircraft which cannot be sent to Iraq or Afghanistan because of computer problems.
The total helicopter fleet operated by the three armed services amounts to 357 battlefield aircraft. One hundred or more are out of commission at any
time, with 79 declared irreparable last year.
An RAF source said more frequent use of helicopters to avoid the risk of roadside booby-traps was exacerbating maintenance problems.
In addition, ground attack jet squadrons' Harriers and Jaguars were cannibalised for spare parts to keep others flying on 930 occasions in 2005.
Of 122 Sea King, Merlin, and Lynx helicopters in the RN's order of battle, 61 were "unfit for purpose" last week.
The MoD said aircraft were judged to be "in service" only when they were "available, reliable, airworthy, and capable of carrying out their missions
on given dates".
A spokesman said that the numbers "fit for service" could vary widely, depending on operational requirements. In an emergency, more would be made operational.
On the Harrier GR7 and Jaguar jets, he added: "The removal of spare parts from one aircraft for use on another is a short-term, temporary measure to
ensure that the maximum number of aircraft are available to the front line."
The figures, revealed in written parliamentary answers, come a year after the Commons public accounts committee warned that the gap between the number of helicopters needed and those available was 20% to 38%.
The MPs said the shortages, though "alarming" had not affected front line capability, but were having an impact on training pilots and crews.
The helicopter shortfall has been worsened by the £259m purchase of eight Chinook Mark 3 heavy-lift aircraft which cannot be sent to Iraq or Afghanistan because of computer problems.
The total helicopter fleet operated by the three armed services amounts to 357 battlefield aircraft. One hundred or more are out of commission at any
time, with 79 declared irreparable last year.
An RAF source said more frequent use of helicopters to avoid the risk of roadside booby-traps was exacerbating maintenance problems.