Re: interesting ETOPS stats from UAL

Date:         06 Jun 98 15:39:23 
From: (H Andrew Chuang)
Organization: Concentric Internet Services
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In article <airliners.1998.802@ohare.Chicago.COM>, Karl Swartz <kls@ohare.Chicago.COM> wrote:
>I have seen stats from engine manufacturers on in-flight shutdowns per
>thousand hours of operation, though.  According to an article in Flight
>International from June 4, 1988, the GE CF6-80C2 had "an engine-caused
>in-flight shutdown rate of 0.009 per 1,000 flying hours."  A subsequent
>article in the April 1, 1989 issue of the same publication claimed the
>CAA requirement for 120-minute ETOPS was that "the engine type must have
>a shutdown rate of fewer than 0.05 per 1,000 flights," with plans to
>tighten that to 0.03 in the future.  Odd that the regulation supposedly
>was written in terms of rate per 1,000 *flights*, versus per 1,000 hours
>as in the GE statistics.  I don't know if that's really the way the
>regulations are (were) written of if it's just an error in the article,
>Rate per 1,000 hours makes more sense to me.

I am ignorant of the progression of ETOPS regulations.  However, nowadays,
to get ETOPS the engine type must have inflight shutdown (IFSD) rate of
less than 0.02 per 1,000 flight *hours*.  The PW4000-94inch and CF6-80C2
are running neck-to-neck, both have IFSD rate at about 0.008 per 1,000
flight hours.  The RB.211-524G/H is slightly worse, but not by much.  The
PW4000-100inch (for the A330) and PW4000-112inch (for the B777) have
pretty low IFSD rates, so does the GE90 (but I think that's because GE is
"babying" the engines in the field).  If my sources are correct, I
believe the Trent engines are not doing very well in this category.