To ask the Secretary of State for Defence how many helicopters of each type in each armed service were (a) in service, (b) in the forward fleet and (c) fit for purpose on the latest date for which figures are available. (319492)

Operational capability is measured in terms of flying hours rather than the number of airframes available. All rotary wing operational requirements are currently being met.

Aircraft defined as available (i.e. fit for purpose) are those within the forward fleet that are considered capable of carrying out their planned missions on a given date. The number of helicopters available varies from day to day due to routine maintenance requirements.

All aircraft in the forward fleet which are not available are classified as short-term unserviceable. Aircraft in this category will be undergoing first-line maintenance, other minor works or being prepared for transportation. Aircraft which are short-term unserviceable can usually be made available relatively quickly.

The in service total includes aircraft in both the forward fleet and the depth fleet. Aircraft in the depth fleet are those undergoing modifications, depth maintenance, repair and those in storage.