Question to the Ministry of Defence:

To ask the Secretary of State for Defence, with reference to Typhoon aircraft in (a) service and (b) storage in the Royal Air Force's fleet, what is the (a) tail number, (b) remaining airframe fatigue life in hours and (c) expected maximum airframe fatigue life of each aircraft.

The Current Fatigue Index (FI) value and Flying Hour clearances, and those expected at Out of Service Date are as follows.

Tranche 1 & 2 Flying Hours - current 4,000 hours, expected to rise to 6,000 hours

Tranche 1 & 2 Fatigue Index - current 66, expected to rise to 100

Tranche 3 Flying Hours - current 3,000 hours, expected to rise to 6,000 hours

Tranche 3 Fatigue Index - current 50, expected to rise to 100

The average FI value across the full Typhoon fleet is currently 23.07.