B737-700
Flight Crew Air Transport Pilot (ATP)
Flight Crew Total 4888.57; Flight Crew Type 2220.73
Communication Breakdown
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural MEL / CDL; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Human Factors; MEL; Procedure
Arrived to airport to delayed flight inbound. Spoke to dispatch about fuel load; and changed from Release (RLS) 01 to RLS02. Whilst investigating details on MEL ZZZ0A and ZZZ7A (the auto-stow feature of the speed-brake was deferred) called DISPATCH back to affirm that the computer system had in fact taken into account the landing weight penalty for ZZZ7A. ZZZ0A requires a secondary MEL be applied when disabling the auto speed-brake. We both noted that the computer system is programmed to ALWAYS take MEL items into account; so we assumed it did but the Captain was not convinced so DISPATCH said he would look into it and call him back. My sharp First Officer figured out that Maintenance had incorrectly applied MEL ZZZ7A to a 737-700 model (it is for 737-800 models) while we were digging into it during flight planning. DISPATCH called back after doing research and speaking to Maintenance Control who had also realized the same error. DISPATCH re-released our flight (RLS03) with the correct MEL (ZZZ7B) for the Auto-Speed-brake deferral. Maintenance came up to the aircraft and changed the MEL to reflect the proper in the paper logbook. After takeoff we received multiple messages from Maintenance Control asking the crew to confirm that the circuit breakers on P-6(2) were pulled and collared. We had done so on our pre-flight prior to departing the gate as part of the checks required of the MEL. Somehow the paperwork got mixed up and Maintenance removed ZZZ0A and not ZZZ7A; so there were multiple add/deletions as noted by DISPATCH; and I am guessing they were not sure if the local maintenance had checked the breakers. The learning point here is that we all have the assumption that the computer system is ALWAYS going to apply the penalty; but it doesn't if it gets bad data (human error in entering the MEL). In this case; improper application of an MEL from a different model of 737 kept a penalty from being applied. This aircraft flew (4) legs on 07 APR after the deferral and prior to this crew asking about the penalty. It appears that there is a hole in the system that allows for an MEL to be applied even if it is not for the correct model. The company was lucky nothing happened on these flights as the aircraft was operated with illegal dispatches. Not sure how much the paper logbook plays into this one; but until such time that this is fixed; recommend that a pilot bulletin be pushed to have pilots [and] dispatchers confirm that MEL's which are aircraft model specific are have been properly applied.
On a B737-700 an incorrect MEL was applied for the auto-stow feature of the speed-brake.