A captain refused a B737-300 with a wing body overheat MEL because of passenger comfort with single ...

Narrative:

The same aircraft was assigned to us for three legs. We noted a MEL of the left wing body overheat sensor. After reviewing the MEL; I felt there was a potential safety problem; in that one system failure could cause several events; e.g.; if due to the fact we couldn't use APU except for start; and left pack shutdown; loss of right engine would cause de-pressurization for one; bird strike anyone? OAT in one destination was approaching 100 degree. I noted that all passengers leaving the aircraft; were either complaining of the heat in the aircraft (right pack only) and or some were rather pale and sweaty looking. Limited to 25;000 ft; with some thunderstorms along some of our routes; further limited options to us for safety of flight. After conferring with dispatch and the chief pilot; we determined for passenger/crew safety to remove the aircraft from service. Flight was subsequently cancelled. Passengers were accommodated on other flights. Some were upset and I'm sorry about that. However; I made this decision after weighing all parameters for safety of flight. Just because the MEL says it's okay; under certain situations; look a little closer at the implications of system failure related to that MEL.

Original NASA ASRS Text

Title: A Captain refused a B737-300 with a WING BODY OVERHEAT MEL because of passenger comfort with single pack operation in hot weather and a flight restricted to FL250 in thunderstorm conditions.

Narrative: The same aircraft was assigned to us for three legs. We noted a MEL of the left wing body overheat sensor. After reviewing the MEL; I felt there was a potential safety problem; in that one system failure could cause several events; e.g.; if due to the fact we couldn't use APU except for start; and left pack shutdown; loss of right engine would cause de-pressurization for one; bird strike anyone? OAT in one destination was approaching 100 degree. I noted that all passengers leaving the aircraft; were either complaining of the heat in the aircraft (right pack only) and or some were rather pale and sweaty looking. Limited to 25;000 FT; with some thunderstorms along some of our routes; further limited options to us for safety of flight. After conferring with Dispatch and the Chief Pilot; we determined for Passenger/Crew safety to remove the aircraft from service. Flight was subsequently cancelled. Passengers were accommodated on other flights. Some were upset and I'm sorry about that. However; I made this decision after weighing all parameters for safety of flight. Just because the MEL says it's okay; under certain situations; look a little closer at the implications of system failure related to that MEL.

Data retrieved from NASA's ASRS site as of April 2012 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	954741
Time
Date	201106
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	B737-300
Operating Under FAR Part	Part 121
Flight Phase	Parked
Flight Plan	IFR
Component
Aircraft Component	Pneumatic Duct Fire/Overheat Warning
Person 1
Function	Captain
Experience	Flight Crew Last 90 Days 194
Events
Anomaly	Aircraft Equipment Problem Critical Deviation - Procedural MEL Deviation - Procedural Published Material / Policy Inflight Event / Encounter Weather / Turbulence

A captain refused a B737-300 with a wing body overheat MEL because of passenger comfort with single pack operation in hot weather and a flight restricted to FL250 in thunderstorm conditions.