You see how the standard of CSD has deteriorated since my day? :roll: I like to think that I'd have managed it a bit more discreetly

First Class??? The only place worse than that would be the crew rest area :o And if I tried to put the body there the crew would have made sure that I soon joined it!
BA 744s don't have anywhere specifically to put a body - it doesn't happen that often. There is no access to the hold or underfloor area during flight except to the nosewheel electrics bay via a hatch in the first class cabin. But it's a bit of a tight squeeze and would be very difficult to do safely. Not really a serious option. As Nigel suggests - why not a toilet? Flights between India and the UK are always full and chaotic and with dozens of staff standing by it is unusual for even a first class seat to be available. Crew jump seats are usually taken as well. A toilet is obvious because you can lock it out of the way and leave it until everybody else has disembarked. The crew rest area will be required for ... crew rest. There is a mandatory requirement for crew to take a rest break, either under flight time limitation regulations or industrial agreements. Start exceeding that and you are looking at terminating the flight short and flying a replacement crew out.
Leif mentions Medlink which is the medical advice centre that most airlines subscribe to. Any medical incident on board and the CSD would be patched through to a doctor who knows exactly what your medical kit contains and where the nearest hospital is that is equipped for your emergency. They usually err on the side of caution and it is unlikely to be the crew's decision to continue the flight. Medlink must have been totally convinced that the person was deceased, so I think there must have been a well qualified doctor on board who confirmed it to them. In which case there is no point in diverting (unless their name is Lazarus).
The only time it happened to me was a Capetown to London service when a middle-aged man had a heart attack about two hours out of London. We diverted to Paris and although he was obviously dead by top of descent, we kept working on him. There were several reasons, not all of them altruistic! The two young doctors who had volunteered both had connecting flights in London and were also thoroughly enjoying themselves with free access to dozens of exotic drugs. We all had a chance to practise CPR and use the defibrillator. Besides, his wife was sitting nearby being distracted by a stewardess and we couldn't be seen to give up for her sake. But most importantly for me was the paperwork involved if he died on board!!! So there was an unspoken agreement that we kept at it until the paramedics wheeled him off. So officially he was alive when he left us

(A French stewardess accompanied the wife to the hospital and stayed with her until she came home - we're not totally heartless!).
And do you remember the BA 744 Captain who passed away in the crew bunk on the Tokyo flight. That was nice and peaceful. When he didn't get up for the landing they asked a stewardess to give him a nudge - so nobody knew until they were almost down. So nothing much to be done in that case. No decisions to make - that's what I like, consideration for others!
Ian
