Flight Crew Air Transport Pilot (ATP)
Communication Breakdown
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Aircraft; MEL; Procedure
An open item; deferred; in the maintenance log for Aircraft X is that the #2 engine regularly exceeds the maximum limit of 4.0 and that [the Air Carrier] has been given a variance by Rolls Royce allowing this as ok. They did not say that when it gets to 4.5 or 5.0 then get worried. It seems to imply that the correct procedure is to wait until the engine fails or falls off. In other words; there is no training or even a suggested substitute procedure. This seems to put the pilot's license in jeopardy; as well as compromising the safety buffer margin that our passengers normally have. I was told that this engine is low time at 16;500 hours and therefore should not be having this problem; implying that is a good reason for ignoring the problem. I was told they have done all the investigation they can; including Boroscope; except remove the engine for a tear down inspection. This seems to say they currently have little or no idea what the real problem is. I was told they just don't want to remove the engine yet.We have our procedures & limits for safety guidance. When we start ignoring them; sooner or later injury or death will follow. Yes this is a rare occurrence; but this engine has reached lemon status. Take the engine off & replace it with one that works.
The Reporter stated that the #2 engine was exceeding the vibration limit of 4.0 according to the Flight Operations Manual (FOM). The Reporter stated that they reported this to maintenance; so maintenance called Rolls Royce and reported back to the flight crew that it was okay to continue in service with this even though the vibration was exceeding the limit. The reporter also stated he felt pressured to fly this airplane in this condition given the fact they had 310 passengers and Rolls Royce said it was good to go. The Reporter also stated that he encountered a vibration of 3.2 in the past and was told to divert to the nearest airport so when he sees an indication exceeding 4.0 and is told that it's okay to continue in service it kind of confusing. The Reporter stated that they could not feel any vibrations in the aircraft; it was just the indication in the secondary engine information page in EICAS that they discovered the engine was vibrating. The Reporter stated that he feels that if an indication is this high and is still good to go; then raise the limit so the flight crews are not put on the spot to take responsibility for an engine exceeding limits. The Reporter stated; as of this report the engine has not been scheduled to be replaced.
[Report narrative contained no additional information.]
The flight crew of a Boeing 777 reported that an engine regularly exceeds the maximum vibration limits.