Thanks Muffin and Bitmonx,
brilliant advice, you have really cleared it up for me, and you were even polite enough not to mention my 'cpl' boo-boo! Of course I meant to type 'ppl'.
This is something I have been aiming at for about twenty years, I'm 44 now, and have made sure that I will have enough, I think... I'll get the plank rating and then try and persuade Dennis Kenyon to come out of retirement and teach me to really fly a helicopter!!!!
Thanks again.