Almost two-thirds of Britain's £2.1bn Apache attack helicopter fleet and more than half of its vital Chinook transport aircraft are "unfit for purpose" and not ready for combat operations, according to Ministry of Defence figures seen by The Herald.

While the frontline availability of both helicopter types is 66% and 47% respectively, this is only being achieved by cannibalising other machines used for training in the UK and diverting the spare parts to Afghanistan and Iraq. Some of the £30m-apiece Apaches are understood to have been stripped for components before they were even declared operational and are now described by attack squadron members as "Christmas trees" because they exist only as a source of parts in short supply.

Army Air Corps sources also claim that only 40% of the trained crews for the Apaches are available and that manpower levels are unlikely to reach more than 60% of that needed in the near future.

Loading article content

The MoD insists that there is no shortage or spares issues for the aircraft flying in close support of troops in Helmand but admits that cannibalisation of the home-based gunships has trebled since 2003 because of the punishing tempo of operations.

Of the 67 Apaches bought by the UK, an average of only 24 - 36% of the total - are in working order at any given time. Only 19 of the 40 Chinooks are in the same category.

Figures released by the MoD show that 251 parts were stripped out of other Apaches in the 12 months up to January 31 this year to keep the eight machines in Helmand available for missions. This compares with 80 incidences in 2003 and 72 in 2004. The MoD said: "All UK helicopters deployed to Iraq and Afghanistan are considered fit for purpose but not all will be available for operational flying each day due to routine maintenance requirements however sufficient helicopters are provided to meet current operational requirements."

The MoD's own target for serviceability is 62% for Apaches and 70% for Chinooks. Both helicopters are seeing intensive service in Afghanistan, where the gunships act as flying artillery for British troops and the transports are vital for moving soldiers over long distances.