Date: 06 Jun 98 15:39:23 From: Chuanga@cris.com (H Andrew Chuang) Organization: Concentric Internet Services References: 1 2 3 Followups: 1
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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.