Al, sorry to hear that John is unwell and visit put on hold for the moment.
Perhaps you might cheer him up by pointing him to the thread "Gaining An R.A.F Pilots Brevet In WW11" in this section (if you haven't done it already!!)
Please stress that it would be invaluable if he could pass on his memories before too late, as cliffnemo and regle are doing.
Just see what reactions those 2 have from all the readers who just can't get enough. I know many don't want to talk about the WW2 losses, but if he doesn't tell, then ALL the memories have gone, the ones who aren't still here as well as his. Even for family use, do get it on tape.
He might say "they're gone but not forgotten" but they will be if he doesn't pass that knowledge on.
I do hope he is strong enough and the BBMF boys can coax him into the Lanc.