Now to refresh and old story about the FAA, Three Engined 727's, over-water flight, and life rafts/life jackets and statistics.
The FAA nodded to Eastern's solicitation to do away with overwater flight required flotation gear for flights between NYC and MIA as the over water portion was a short time and not all that far offshore. With permission granted....Eastern removed all the extra weight of the floation gear.
Less than two weeks later....a FE managed to starve all three engines of fuel...caused all three engines to fail nearly simultaneously...smack dab in the middle of the overwater portion of the flight.
The Crew was able to sort out the situation...restarted the engines...and only got a close look at the Oggin.
The over water gear went back into the aircraft....and I would suppose the FE got the ass kicking of his life shortly after landing!
Statistics are just that statistics....the probability of a second engine failure immediately following the failure of the other engine is only a guess and not a guarantee. They are independent events. There is no guarantee an engine will last more than 30 seconds after installation or that it will go to TBO. Five hours is a very long time to be hanging on one Donk in something like an Air Bus or Boeing with hundreds of folks wondering about how they have lived their lives and wondering about the final tally!
When the first Donk dies.....you are now rolling the dice big time....each second that goes by is another roll of the dice. I like to hedge my bets so I don't lose everything.
There is no such thing as too much power...too many engines....too much fuel.