OK thanks, Unfortunately I explained this to my FO on the day and ( as is always the case with the challenge everything brigade ) he comes back with " where is that written". I don't really mind that (as it also serves to protect against a huge amount of cross cockpit hot air)...but it would be great to be able to point this out as a reference if someone was willing and able to dig it out. Would like to take you up on the offer of a visit...any contact details? Thanks again.