If I might offer some information on F-35 variant weights and ranges: The latest information out there shows the following empty weights:
F-35A: 28,999 lb
F-35B: 32,442 lb
F-35C: 34,581 lb
So, F-35C is about 5,400 lbs heavier than the A. That cat and trap stuff adds a lot of weight all over the aircraft, especially in the stronger structure required to handle launch and landing loads. The low speed precision approach also demands a larger wing, fins, tails and control surfaces.
However, there's a bit of a surprise in the stated combat radius. Here are the figures, with threshold and objective (target and 'must achieve') figures shown in brackets afterwards:
F-35A: 669 mi (690/590)
F-35B: 505 mi (550/450)
F-35C: 640 mi (730/600)
My guess here is that the F-35C's extra weight and drag has caught up with it, and despite its additional fuel it just burns more to get out there. However, it still (just) meets the objective requirement. On this data, the A model looks like the right one for the RAF, but the AAR issue probably needs to be sorted.
Best regards as ever to all those working the flight test programmes - this is tough and complex stuff.
Engines