Originally Posted by
CurtainTwitcher
Are they? Do you have a statistical source for this? The central assumption behind ETOPS is that cruise engine failures are independent of one another with one engine operating at Max Continuous Thrust for the maximum ETOPS time limit.
If there is a dependant relationship between the two engines (common fuel source or an engine failure damages another engine) then this assumption is no longer valid, and getting on the ground ASAP is a must.
Oh please. This isn't about statistics. This is about airmanship and conservative thinking. If one engine is carrying the load of two, especially with all that vibrating and shaking going on, it IS subject to more stress and loads than it normally operates with. It makes it more likely to fail than it did.
And Captains don't go on statistics and all that other waffle you put up. They think of the worst case scenario and plan for it. No Captain I know would have flown past a suitable runway on one engine with hundreds of kms to go to destination.