Two 777 Engine
diversions in 1 day
being reported that UA 777 flying FRA-IAD diverted to
KEF [Keflavik] (PW powered) and a CO 777 NRT-HOU [Narita
to Houston] (GE powered) diverted into Midway. At a
rough count that makes 4 engine-related diversions,
all while over water in 6-8 weeks [1 GE90 into Dublin
+ 1 GE90 into Fortaleeza, Brazil]
Are we seeing something here that with the benefit of hindsight
may prove to be significant, equipment ages, and not always at
the rate the manufacturer expects.
Personally I have always thought that the 2 engine failure
statistics are misunderstood, even if it is predicted
10 million flight hours
1) It is predicted to happen sometime
2) That statistic doesn't discount 3 tomorrow and no more for
Added to this there is something I like to refer to as Shuttle
Mathematics. Back in 1980 it was predicted that the shuttle
system would fail once in 10,000 launches (or something like
that) after Challenger that figure was reduced to 1 in less than
100, ie you would lose another one before completion of the ISS.
I think the actual stats now show a 2 in 107.
What this tells us is that stats are just numbers built
on assumptions and that in real life experience can
sometimes prove them to be worthless - especially when
there is pressure for the "right result" from
Getting to the point, I doubt that 2 of the above diversions
were in ETOPS sectors so they will not even find their
way into the IFE stats, further distorting the real
world reliability stats. I will also throw the Trent
800 (un)contained failure at MEL [Melbourne] into this
Who's keeping score? how are these stats arrived at?
is there any independent non-regulatory input. Are the
regulators too close to the Airlines?