Tourist, absolutely no bite - it was the plan for the Cranwell Jetstream replacement about 5 years ago, but as I said another contractor proposed a different solution and that was the one that was taken up. The concept of "call off" contracts with "take or pay" levels (manhours, flying hours, tug movements etc) and banded additional variations whilst the contractor takes "third party" useage risk is a well worn path in many contracts to the MoD. Don't see anything wrong with that myself, although I accept that if there is no money in the pot at all because the requirement has been written out then that's tough.