To ask the Secretary of State for Defence what the average unit tour interval was for each ship type in the Royal Navy over the last eight years. (249708)

The average tour unit interval by surface ship type, defined as a ship being away from its base port for more than three months, from 2003 for which information is available is as follows (rounded to the nearest month):

Exceptions

Survey Vessels have up to two and a half year deployments.

River Class Patrol Vessels on Fishery Protection undertake eight week (approx) taskings.

Falkland Island Patrol Vessel permanently deployed.