Narrative:

The aircraft arrived late into ZZZ. The continuing flight was originally scheduled to depart ZZZ1 at XA05. When the paperwork was pulled up earlier there were 3 MEL's on the aircraft to include: 27-13B #1 stall warn system inoperative 27-12 autoslat system inoperative 33-7 r-hand wing illumination light inoperative. The first concern is that there were multiple MEL's on a single aircraft of which 2 of them are flight control issues. Through further investigation we determined that 27-13B also disables the yaw damper and that the circuit breaker is to be pulled and collared. However; we believe that MEL 27-13B should also incorporate MEL 22-3A yaw damper inoperative and the associated notes and procedures that go along with that MEL. One of which is plan the flight at FL290 and below. Our flight was planned at FL370 and no consideration was given to the yaw damper being disabled. The WX was less than 5 mi visibility with gusty winds and rain. The previous flight left ZZZ2 and flew at 16000 ft; and on arrival had to be cleaned because of several people getting sick in the back of the airplane. The yaw damper along with the poor WX created a very rough ride for the aircraft. Another problem for the aircraft and one that concerned us was that the initial write-up with the stall warn system was that it written up in ZZZ the day before. The system was signed off by just resetting the circuit breaker and then conducting only a flight deck stick shaker test without investigating the actual cause of the malfunction. We asked the mechanic if there was any other tests that could be done to inspect this problem. He told us that a bite check on the system should be done. We asked him if he would do the bite test for us. When he did the bite test he not only found a problem on our #1 system; but also on the #2 system. He said that there were faults on both system for the last 10; yes I said 10; flts. We were astonished that this was not discovered in ZZZ1; one of our maintenance bases! Consequently; after departing ZZZ1 and arriving in ZZZ2 the aircraft again failed the test; MEL 27-13B was issued; and this is where we started our preflight on aircraft. The major concern for us is that this aircraft went through 2 company maintenance bases where an important system; integral to other system; had an existing issue. There seems to be no defined process to determine the root cause of the problem. Priority is clearly operational completion above safety; at least in this case; and was considered more important as well to passenger comfort and safety. Another outstanding concern is the inadequacies in the B737 MEL that would allow for flight to be dispatched to FL370 well above the FL290 for an inoperative yaw damper. Flight XXX was delayed nearly 3 hours including the aircraft swap. The disturbing part is when a flight is delayed that long; it seems to fall by the wayside. Ground service; baggage handling; catering and general customer service were severely lacking. This added to the delay and passenger frustration. Corrective action: 1) complete audit of the MEL program; and especially the B737 MEL itself in order to incorporate some type of xref for all affected system. 2) review all processes for company maintenance base troubleshooting and system fault analysis.

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Original NASA ASRS Text

Title: B737 NG CREW RECEIVES ACFT WITH NUMEROUS MEL'S; ONE OF WHICH HAS NOT BEEN PROPERLY DIAGNOSED AND THE MEL NOT COMPLIED WITH. THIS RENDERS THE ACFT NOT AIR WORTHY AND AN ACFT CHANGE RESULTS.

Narrative: THE ACFT ARRIVED LATE INTO ZZZ. THE CONTINUING FLT WAS ORIGINALLY SCHEDULED TO DEPART ZZZ1 AT XA05. WHEN THE PAPERWORK WAS PULLED UP EARLIER THERE WERE 3 MEL'S ON THE ACFT TO INCLUDE: 27-13B #1 STALL WARN SYS INOP 27-12 AUTOSLAT SYS INOP 33-7 R-HAND WING ILLUMINATION LIGHT INOP. THE FIRST CONCERN IS THAT THERE WERE MULTIPLE MEL'S ON A SINGLE ACFT OF WHICH 2 OF THEM ARE FLT CTL ISSUES. THROUGH FURTHER INVESTIGATION WE DETERMINED THAT 27-13B ALSO DISABLES THE YAW DAMPER AND THAT THE CIRCUIT BREAKER IS TO BE PULLED AND COLLARED. HOWEVER; WE BELIEVE THAT MEL 27-13B SHOULD ALSO INCORPORATE MEL 22-3A YAW DAMPER INOP AND THE ASSOCIATED NOTES AND PROCS THAT GO ALONG WITH THAT MEL. ONE OF WHICH IS PLAN THE FLT AT FL290 AND BELOW. OUR FLT WAS PLANNED AT FL370 AND NO CONSIDERATION WAS GIVEN TO THE YAW DAMPER BEING DISABLED. THE WX WAS LESS THAN 5 MI VISIBILITY WITH GUSTY WINDS AND RAIN. THE PREVIOUS FLT LEFT ZZZ2 AND FLEW AT 16000 FT; AND ON ARR HAD TO BE CLEANED BECAUSE OF SEVERAL PEOPLE GETTING SICK IN THE BACK OF THE AIRPLANE. THE YAW DAMPER ALONG WITH THE POOR WX CREATED A VERY ROUGH RIDE FOR THE ACFT. ANOTHER PROB FOR THE ACFT AND ONE THAT CONCERNED US WAS THAT THE INITIAL WRITE-UP WITH THE STALL WARN SYS WAS THAT IT WRITTEN UP IN ZZZ THE DAY BEFORE. THE SYS WAS SIGNED OFF BY JUST RESETTING THE CIRCUIT BREAKER AND THEN CONDUCTING ONLY A FLT DECK STICK SHAKER TEST WITHOUT INVESTIGATING THE ACTUAL CAUSE OF THE MALFUNCTION. WE ASKED THE MECH IF THERE WAS ANY OTHER TESTS THAT COULD BE DONE TO INSPECT THIS PROB. HE TOLD US THAT A BITE CHK ON THE SYS SHOULD BE DONE. WE ASKED HIM IF HE WOULD DO THE BITE TEST FOR US. WHEN HE DID THE BITE TEST HE NOT ONLY FOUND A PROB ON OUR #1 SYS; BUT ALSO ON THE #2 SYS. HE SAID THAT THERE WERE FAULTS ON BOTH SYS FOR THE LAST 10; YES I SAID 10; FLTS. WE WERE ASTONISHED THAT THIS WAS NOT DISCOVERED IN ZZZ1; ONE OF OUR MAINT BASES! CONSEQUENTLY; AFTER DEPARTING ZZZ1 AND ARRIVING IN ZZZ2 THE ACFT AGAIN FAILED THE TEST; MEL 27-13B WAS ISSUED; AND THIS IS WHERE WE STARTED OUR PREFLT ON ACFT. THE MAJOR CONCERN FOR US IS THAT THIS ACFT WENT THROUGH 2 COMPANY MAINT BASES WHERE AN IMPORTANT SYS; INTEGRAL TO OTHER SYS; HAD AN EXISTING ISSUE. THERE SEEMS TO BE NO DEFINED PROCESS TO DETERMINE THE ROOT CAUSE OF THE PROB. PRIORITY IS CLRLY OPERATIONAL COMPLETION ABOVE SAFETY; AT LEAST IN THIS CASE; AND WAS CONSIDERED MORE IMPORTANT AS WELL TO PAX COMFORT AND SAFETY. ANOTHER OUTSTANDING CONCERN IS THE INADEQUACIES IN THE B737 MEL THAT WOULD ALLOW FOR FLT TO BE DISPATCHED TO FL370 WELL ABOVE THE FL290 FOR AN INOP YAW DAMPER. FLT XXX WAS DELAYED NEARLY 3 HRS INCLUDING THE ACFT SWAP. THE DISTURBING PART IS WHEN A FLT IS DELAYED THAT LONG; IT SEEMS TO FALL BY THE WAYSIDE. GND SVC; BAGGAGE HANDLING; CATERING AND GENERAL CUSTOMER SVC WERE SEVERELY LACKING. THIS ADDED TO THE DELAY AND PAX FRUSTRATION. CORRECTIVE ACTION: 1) COMPLETE AUDIT OF THE MEL PROGRAM; AND ESPECIALLY THE B737 MEL ITSELF IN ORDER TO INCORPORATE SOME TYPE OF XREF FOR ALL AFFECTED SYS. 2) REVIEW ALL PROCESSES FOR COMPANY MAINT BASE TROUBLESHOOTING AND SYS FAULT ANALYSIS.

Data retrieved from NASA's ASRS site as of January 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.