View Full Version : A320/V2500 P2/T2 probe issues
allenkey
31st Mar 2007, 17:59
Our airline has been experiencing many RTOs due to uneven acceleration of engines (A320/V2500). There were even several reports of EPR mismatch during climb. In all cases, the P2/T2 probe was the culprit......cleaning or replacing it solved the problem. In most cases, dead insects were found blocking the probe.
Questions:
Is this a common industry problem?
Any solutions implemented by anyone?
A somewhat expensive remedy but our airline went down the route of only using CFM engined busses :D
Cured the rotor bow problem too :ok:
allenkey
1st Apr 2007, 07:52
Thanks Mono, but we are looking for solutions a little less dearer. BTW, we have A5 only, so no rotor bow headaches.
Perrin
1st Apr 2007, 09:12
Boy does this bring back the times in Guam with B-52's, we had all kinds of problems with bugs blocking the PT2 probe had to disconnect and blow out each one and as the old bird had 8 engines it wasn't a great job. Answer was for the really good gound crews to put blanks on till preflight. The question is will aircrews take the blanks off??????????? There is no answer to that one.
Keep them going boys:ugh:
scarebus03
4th Apr 2007, 13:19
Have you studied the frequency of these occurences i.e time between A-checks etc? A solution could be to add the cleaning task into the weekly check or every A-check.
Brgds
SB03
N1 Vibes
5th Apr 2007, 10:59
Yes,
we had one here on a KA 320. It was a large bee in the sensing line. Not seen this before or since, guess that the architecture of the probe on the V2500 is easy for insects to get into.
Best Regards,
N1 Vibes
PS Yes it was half-a-bee when we recovered it, and no it's name wasn't Eric!!
allthatglitters
7th Apr 2007, 06:54
we currently boroscope the probes looking for insects and debbris at about A check time. (600 Flt Hrs)
wildadv
17th Apr 2007, 01:07
We had an interesting problem on one of our 320's out here in SE Asia.
On the T/O roll, one engine wouldn't accelerate as quickly as the other, all accel checks couldn't fault the accel times, and all TSM procedures followed didn't help. The TO report from AIDS showed a difference in the T2 readings of a few degrees, but all wiring checks were OK.
What we found after a little suggestion from our IAE rep was to shove a very small boroscope up the back of the T2 sensing element chamber and look for obstructions. Found some leaf material in there. Cleaned this out and no further problems.
What we surmised is that this material blocks the airflow through the small cooling holes in the probe. When the P2 probe heater energises, this heat can now get transferred through to the T2 sensing elements because the cooling holes are now blocked, which then affects the fuel flow scheduling, thus accel problems. At the time, the TSM didn't cover this at all (not sure if it does even now).
An airline in China changed heaps of components for the same accel fault, only cured the fault after they changed the P2T2 probe by default (same T2 split)(surprise, surprise, surprise).
Hope this helps.