B737 captain reported that he refused an aircraft due to safety concerns over an MEL that was not be...

Narrative:

The referenced aircraft was flown to ZZZ by another crew whereupon we were to receive the aircraft and use it to operate [the next flight]. The number 2 engine fire detection/protection system had been degraded to a single loop status based on an undetermined malfunction having occurred earlier either in ZZZ1 or a prior station. I conferred with [maintenance control] regarding the MEL and it was made clear that no repair attempts would be made in ZZZ and that the aircraft could continue to operate in this degraded mode for as long as 10 days. I then contacted my dispatcher and informed him that I would refuse the aircraft based on an unacceptably elevated and prolonged level of safety risk. While this is an MEL-able item; it is my position that extended operation of such an aircraft by the company is an unsound course of action and that the aircraft should not continue to pass through company maintenance hubs without repairs being made. My dispatcher concurred and supported my refusal decision. A brief conference call was made with [maintenance control] prior to my full refusal. Within five minutes of my decision; I was contacted by chief pilot who asked for an explanation regarding my refusal. I briefly offered same as stated above. Captain asked if I desired assistance from any fleet staff regarding my refusal decision to which I respectfully responded 'no; thank you.' during my brief conversation with captain; I detected no support for my decision nor was I overtly criticized for my action by captain.

Original NASA ASRS Text

Title: B737 Captain reported that he refused an aircraft due to safety concerns over an MEL that was not being addressed for repair; but continued in service.

Narrative: The referenced aircraft was flown to ZZZ by another crew whereupon we were to receive the aircraft and use it to operate [the next flight]. The Number 2 engine fire detection/protection system had been degraded to a single loop status based on an undetermined malfunction having occurred earlier either in ZZZ1 or a prior station. I conferred with [Maintenance Control] regarding the MEL and it was made clear that no repair attempts would be made in ZZZ and that the aircraft could continue to operate in this degraded mode for as long as 10 days. I then contacted my Dispatcher and informed him that I would refuse the aircraft based on an unacceptably elevated and prolonged level of safety risk. While this is an MEL-able item; it is my position that extended operation of such an aircraft by the company is an unsound course of action and that the aircraft should not continue to pass through company Maintenance hubs without repairs being made. My Dispatcher concurred and supported my refusal decision. A brief conference call was made with [Maintenance Control] prior to my full refusal. Within five minutes of my decision; I was contacted by Chief Pilot who asked for an explanation regarding my refusal. I briefly offered same as stated above. Captain asked if I desired assistance from any fleet staff regarding my refusal decision to which I respectfully responded 'No; thank you.' During my brief conversation with Captain; I detected no support for my decision nor was I overtly criticized for my action by Captain.

Data retrieved from NASA's ASRS site 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.

Attributes
ACN	1681658
Time
Date	201909
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	B737 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Parked
Flight Plan	IFR
Component
Aircraft Component	Fire/Overheat Warning
Person 1
Function	Captain Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Instrument Flight Crew Multiengine
Experience	Flight Crew Last 90 Days 215 Flight Crew Total 7933 Flight Crew Type 4476
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural Maintenance Deviation - Procedural MEL Deviation - Procedural Published Material / Policy

B737 captain reported that he refused an aircraft due to safety concerns over an MEL that was not being addressed for repair; but continued in service.