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I read this news:

http://edition.cnn.com/2016/04/23/us/boeing-dreamliner-engine-fix/index.html

So seemingly the reliability of the 787 engines made by General Electric is not as high as expected and need to be overhauled to increase reliability. If one engine fails due to icing there should be also increased chances that the second one may fail as well. Does it mean that - even temporarily - this may have an effect on the plane's ETOPS rating?

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Every time an engine is shut down in flight, it is tracked.

Engine reliability does affect ETOPS certification. In addition to the aircraft being certified, each airline is also ETOPS certified. An aircraft or an airline with a poor record could have its ETOPS certification downgraded, or even potentially revoked.

Wikipedia ETOPS Approval

ETOPS approval is a two-step process. First, the airframe and engine combination must satisfy the basic ETOPS requirements during its type certification. This is called "ETOPS type approval". Such tests may include shutting down an engine and flying the remaining engine during the complete diversion time. Often such tests are performed in the middle of the ocean. It must be demonstrated that, during the diversion flight, the flight crew is not unduly burdened by extra workload due to the lost engine and that the probability of the remaining engine failing is extremely remote. For example, if an aircraft is rated for ETOPS-180, it means that it should be able to fly with full load and just one engine for 3 hours.

Second, an operator who conducts ETOPS flights must satisfy their own country's aviation regulators about their ability to conduct ETOPS flights. This is called "ETOPS operational certification" and involves compliance with additional special engineering and flight crew procedures in addition to the normal engineering and flight procedures. Pilots and engineering staff must be qualified and trained for ETOPS. An airline with extensive experience operating long distance flights may be awarded ETOPS operational approval immediately, others may need to demonstrate ability through a series of ETOPS proving flights.

Regulators closely watch the ETOPS performance of both type certificate holders and their affiliated airlines. Any technical incidents during an ETOPS flight must be recorded. From the data collected, the reliability of the particular airframe-engine combination is measured and statistics published. The figures must be within limits of type certifications. Of course, the figures required for ETOPS-180 will always be more stringent than ETOPS-120. Unsatisfactory figures would lead to a downgrade, or worse, suspension of ETOPS capabilities either for the type certificate holder or the airline.

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  • $\begingroup$ Although perhaps worth noting that in this case there could potentially be a different ETOPS rating for GE and RR engined 777's, in which case we'd potentially see airlines re-engine their aircraft: whether it would happen depends on whether the cost of changing the routes outweighs the cost of switching $\endgroup$ – Jon Story Apr 25 '16 at 15:36

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