B737 Undifferentiated or Other Model
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 230; Flight Crew Total 20000; Flight Crew Type 13000
Troubleshooting; Communication Breakdown; Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural MEL / CDL; Deviation / Discrepancy - Procedural Maintenance
General None Reported / Taken
Aircraft; Company Policy; Procedure
During taxi out the left pack light illuminated. Called tower and got out of line; set brakes and worked the problem. Read and did QRH selected warmer temp and trip reset switch pushed. the left pack light remained illuminated QRH says Isolation valve switch close pack switch off. I called dispatch for a conference call with [Maintenance Control]. We walked thru [the associated procedure]. Push master caution light and observed that the aircond; master caution; and pack lights extinguished. We determined with dispatch; maintenance; capt and fo that we were good to takeoff. Arrived at [our destination] and recieved acars message from dispatch saying a safety report will be completed concerning the flight. Safety is my number one priority.
On a related note; during my annual recurrent training the week prior; I was asked a hypothetical question about a similar situation. I was asked; if during master caution recall; you get a caution light; but you are able to clear it during reset; what do you have to do. I was told by the Standards Captain that this is a fault in a redundant system and that you should not run a QRH checklist and proceed to your destination and write it up there...it seemed to me that maintenance was understanding what was happening and that they were telling the Capt. to write it up [at our destination]. This confirmed what I was recently told in training. In my mind we were good to go; the pack was operating normally on the back up system; so there was nothing to defer.After further researching this today; I have not been able to find anywhere in my manuals that says to proceed to your destination with redundant system faults as I was told. Also; there appears to be an MEL for the situation we had. I don't know how maintenance missed that.
Despite the conjoined efforts of the B737 flight crew; Dispatch and Maintenance Control the procedure utilized to correct a left pack off light was apparently deemed inappropriate after the fact and the decision to fly the trip technically a violation.