MD-82
Flight Crew Air Transport Pilot (ATP)
Training / Qualification; Human-Machine Interface; Troubleshooting
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy
General Work Refused; General Maintenance Action; General Flight Cancelled / Delayed
Human Factors; Procedure; Aircraft
After takeoff I noticed what I thought was an abnormally high pneumatic duct pressure - 70 PSI. We discussed the condition and looked in the QRH and the Aircraft Operating Manual for guidance. Finding none; I noted the duct pressure at several different altitudes/power settings for a possible logbook write up. Aware that there used to be a procedure for bleeding this duct pressure off by use of the airfoil anti-ice system and that now the procedure doesn't exist I decided to call Maintenance Control for advice prior to making any logbook entries. During those communications I was asked to take the aircraft on the next flight and troubleshoot the system by activating the airfoil anti-ice system. At this point I decided the system was not in proper working order and decided to enter [the discrepancy] into the logbook. Eventually the aircraft was taken out of service for repair/troubleshooting. Another consideration for electing not to troubleshoot the problem on the next leg was that our previous [but no longer published] procedure called for activation of the airfoil anti-ice switch while leaving the crossfeeds closed to drain the pressure build up. This meant that activation of the airfoil anti-ice switch would have activated the system for two and a half minutes; [a period of exposure I deemed to be unacceptable]. Our airline needs to remind Maintenance not to advise or suggest that flight crews do troubleshooting during revenue flights; especially using a procedure that no longer exists. I believe the Technician that I spoke with was well intended in his advice but; nonetheless; doing so was not the proper action given [currently published procedures].
An MD-82 Captain was unwilling to accept the Maintenance request that he fly his next leg in an aircraft displaying symptoms of a pneumatic system problem in order to troubleshoot the system using a no longer current procedure. After landing the aircraft was taken out of service.