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Old 21st Jan 2023, 19:16
  #139 (permalink)  
tdracer
 
Join Date: Jul 2013
Location: Everett, WA
Age: 68
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Originally Posted by Dick Smith
Two engines over long oceans is a classic example of affordable safety!
You're under the mistaken assumption that more than two engines automatically makes it safer. Statistically, there is no basis for that.
While more than two engines makes it less likely you'll experience an all engine power loss, it increases the probability of experiencing a catastrophic engine failure - e.g. engine fire, uncontained failure that damages critical systems, etc.
As long as there is a certain level of engine reliability (which is required by ETOPS), when you add engines (above two), the increase in probability of a catastrophic engine failure is greater than the reduction in probability of an all engine power loss.

BTW, I didn't make that up - it's the entire basis of ETOPS.
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