GE 90 fan balance

GE 90 fan balance

Postby f4dj79 on Tue Mar 31, 2009 8:40 am

Occasionaly we get to do a fan balance on these big round things (BRT's). The ease of the balance on the 777 is this. Go to the maintenance access terminal, access the the engine data, look up the last engine operation, ask the computer to plot and give a solution, go out to the fan adjust the weights. The next step is the fun part ,do a high power engine run, usually we get these engines up to 105%. Now I do not know if anyone has ever been aboard a heavy when doing the high power ground runs but the airplane really jumps around. It is impossible to read data or take notes, (we are spoiled) we simply push the record button and read or print the data later. I bring this up because we had an engine with N1 (fan) reading of 1.6 during flight. This may not seem like a lot, but trust me it will shake your filling out. The answer as to why this happen to airplane with five flights before this showed up was simple. The mechanic that did the inital engine run noticed the engine was alittle high and did not address this (what the h was he thinking) I get neverous when an engine gets a .5-.6 N1 reading. So let that be a lesson for everyone reading this if the engine is just alittle out balance fix it right away. Each one of our 777 flight costs $45,000, now we have to fly one more flight to verify that the balance adjustments worked.
Posts: 153
Joined: Tue Jan 13, 2009 4:42 pm

Re: GE 90 fan balance

Postby UtahTurbineMan on Mon May 07, 2012 6:29 am

Ah, to work on a GE-90 would make some of us jealous.... Anyways an N1 reading at 1.6 is insane! I cant believe the mechanic would let that slide when he read it at .5 even.
Posts: 7
Joined: Sat Apr 21, 2012 5:32 am

Return to GE-90

Who is online

Users browsing this forum: No registered users and 1 guest