View Full Version : IAE 2500-A1 N1>n2

16th Sep 2007, 16:45
got one question above RPM.

I had one flight from CMB to AUH, The aircraft climb above OPT ALT. I found both engine N1>N2, anybody knows why?

Thanks in advance.

17th Sep 2007, 01:58
Very high TAT?

(PS - Even though the percent indication for N1 appeared greater than N2, the 100% references for the two are very different. Trust me, if you did the math, N2 was still much greater than N1) :8

17th Sep 2007, 06:34
SAT is -43, i am not sure about TAT, actually this is very old engine, IAE 2500-A1.

17th Sep 2007, 10:26
barit1 is correct, you cannot compare N1 vs N2. It is a percentage value of rated N1 or N2. Seen this many a time on type :)

17th Sep 2007, 14:08
If SAT is -43, then TAT will be in the vicinity of -15 or -16 which does seem pretty high.

20th Sep 2007, 09:39
I will ask you more people, thanks a lot