Hi all,
anyone had the following go-on with a C28B
Had the unit overhauled last year or so, worked fine 14% N1 introduce fuel - bingo off she goes. Stayed like this for approx 25hours then refused to light off at 14-12- even 10%. Spoke with RR they say that the compressor is so efficent (it was re-worked and set up in test cell) that it pushes so much air at lower N1 speeds, advised they did some C30's that light off at 5% - they sugested we try 6-8% . Since then if starts everytime at this range, peak TOT 790- 800c then quickly drops (have to be very careful when cracking the throttle though also quick re-starts as the TOT can get all outta hand real quick) one other issue is we cannot get it to stay in the 740-800C range for starting, dos'nt matter how we try the TOT always drops off to 680 ish in the 38-50% N1 range. Messed with the fuel settings and its the best we can get from her. I've got to ask this question caus it sometimes drives me nutz, pax on board, hit the starter miss 6-8% and sit there all the way to 18% trying to coax a light off - nothing. Wait for the N1 to go all way to zero - do it again - but now with added pressure of unburnt fuel in the can! All in a days work right!
Other than that she's a cracker + 9 at the last power count
Do we have a duffer or is RR onto something?
