Litebulbs,
There are only two UK based shorthaul operators from LHR, BA and BMI. Average expenditure, as opposed to salary, per head (cabin crew) is as follows (in 000's, using 2007 figures):
BMI 13.7
BA 28.7
This doesn't distinguish between shorthaul and longhaul as clearly, BA's operation, especially in LH is significantly bigger than BMI. However, it does include BA's LGW shorthaul op which is significantly lower cost.
By contrast, Virgin are entirely a LH operation whilst Easyjet are entirely shorthaul (although not LHR).
Virgin 14.1
Easyjet 20.5
Make what you will of the figures, which come from
HERE.