Janet, the answer is just five posts above yours in the link I included...
Its a bit optimistic I think to assume that wreckage "would" be found from a ditching off Africa. Even if some did wash ashore somewhere the shoreline is so vast it might well never be spotted, let alone recognised. Even less likely reported. There is not necessarily any wreckage at all if the ditching was reasonably controlled, nor much in the way of fuel leakage. There is noting to say it gets washed ashore in Africa if the currents take it in another direction. If it crashed the 727 is all metal and readily identifiable bits don't float like some modern plastic structure. Fuel will disperse and evaporate considerably in 3 days, and anyone naiive enough to imagine you can search the humungous area within the range of that aircraft travelling on an unknown track is simply deluding themselves. It isn't the English Channel!