Bismark;
It has just been reported that PW is going to the FIs for 6 weeks rotation - what does such a short rotation cost? Why not 6 months rotation like the RN do down there.
Send a UK SAR crew to the FI for 6 months and all SAR orientated currency starts to fall away. Yes, you can work 24 on, 24 off, for 6 months with your two 4 man crews, (with the regular incursions into your 24 off) but it would become debilitating after a very short period. I've done it loads of times (24 on/off, that is).
The training required to recover UK flying awareness after 6 months away would be a significant cost, and, as there is a paucity of crews, a 6 week rotation is actually cost effective in returning a crew as quickly as possible back to UK SAROp standard, and maintain the expertise that the UK needs.
The deployed time for a SAR crew to the FI is a balance; to retain optimum skills at UK and MPA, with minimum time (and cost) to get back online, and do it safely.
Different ships, different cap tallies. When the RN deploy for 6 months, they don't go and do another 6 monther on return to the UK. The tightly manned UKSARF (RN/RAF/CG) is watchon-stopon, all the time.
In summary; Manpower available (Cost), Maintaining skillset (Cost), Flight Safety (....).