Still holding your breath, Sir George?
There is one very large problem with "lost comms": It will often be the case that your flight plan details have not been passed to the next FIR!
The normal "lost comm" procedure assumes that the ATC facility has your flight plan details. Not usually so over Africa, I am afraid. This is why you are required to call ten minutes before entering the Lagos FIR, for instance; they need to get your details. Essentially, you are air-filing your flight plan then and there and never mind what you did before departure!
I had a trip from Gao, Mali to Marrakesh, Morocco where we were out of contact on all frequencies for most of the trip, and don't ask me why. It was a quiet time of day so that we couldn't get a relay on VHF, no one was answering our calls on HF... we just went motoring along at F350 or whatever it was until we finally managed to make contact on some odd frequency I picked off the chart, with another aircraft way off towards Dakar, nothing for our route of flight at all, when they were kind enough to pass our details.
The other aircraft told us to call on some VHF frequency that wasn't listed, when we were using current charts of course, and then we were back in business. It is just... Africa. Relay stations don't work, frequency changes aren't notified, "everybody" knows to call on XXX, well, everybody but you!
One thing I would always try to do is get cleared to my cruising altitude as soon as possible so that if I did lose comms at least I was up there getting good fuel consumption. Being stuck down low is double trouble with poor line-of-sight and lousy fuel consumption. That can feel like torture.
Another thing is that if you are communicating with a basically non-Anglophone ground facility make your calls slowly and clearly. I had one FO who just had to rap everything out at a rapid pace speaking to Libreville when he would get... nothing. I often had to give him the airplane and put on my friendliest voice to get them to reply in English. They were there all along; they just didn't want to answer! Hey, it is just human nature; no one likes to be made to look stupid.
It is a big, empty sky over Africa but it sure does pay to call on 126.9 and to keep a look-out. That much we can do for ourselves, when the rest can be problematic, yes indeedy.