The air carrier flight crew of an large transport reset the right air conditioning system during taxi out and it returns to normal operation. This system had been MEL'ed and the aircraft had been restr to a maximum altitude of FL35O on the dispatch release. The flight crew climbed to FL370 in violation of the release since the air conditioning and pressurization system now worked normally.

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Attributes
ACN	366480
Time
Date	199704
Day	Thu
Local Time Of Day	1201 To 1800
Place
Locale Reference	atc facility : bke
State Reference	OR
Altitude	msl bound lower : 35000 msl bound upper : 37000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	artcc : zse tower : sat
Operator	common carrier : air carrier
Make Model Name	Commercial Fixed Wing
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	cruise other
Route In Use	enroute airway : zse
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : atp pilot : flight engineer
Experience	flight time last 90 days : 210 flight time total : 9800 flight time type : 2800
ASRS Report	366480
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Experience	flight time last 90 days : 150 flight time total : 17000 flight time type : 1500
ASRS Report	366282
Events
Anomaly	aircraft equipment problem : less severe non adherence : far non adherence : published procedure other anomaly other
Independent Detector	other flight crewa other other : unspecified
Resolutory Action	flight crew : returned to intended course or assigned course other
Consequence	Other
Supplementary
Primary Problem	Flight Crew Human Performance
Air Traffic Incident	Pilot Deviation

Narrative:

During boarding at the gate in seattle, the right air conditioning pack tripped off due to a momentary overheat. It was written up in the aircraft logbook, and a mechanic signed it as a maintenance carry-over. On taxi out, we were able to reset pack to normal operation (for best safety/redundancy of system), and took off with all system operating normally. During cruise, we accepted FL370. However, because the pack was technically inoperative on paper, the MEL dispatch altitude is a maximum of FL350. We were advised of this by our dispatcher, and we immediately requested a lower altitude of FL330 for the duration of cruise. Safety of flight was never compromised, but this is a technicality of being dispatched for flight with something originally inoperative, even though it works for the duration of the day.

Original NASA ASRS Text

Title: THE ACR FLC OF AN LGT RESET THE R AIR CONDITIONING SYS DURING TAXI OUT AND IT RETURNS TO NORMAL OP. THIS SYS HAD BEEN MEL'ED AND THE ACFT HAD BEEN RESTR TO A MAX ALT OF FL35O ON THE DISPATCH RELEASE. THE FLC CLBED TO FL370 IN VIOLATION OF THE RELEASE SINCE THE AIR CONDITIONING AND PRESSURIZATION SYS NOW WORKED NORMALLY.

Narrative: DURING BOARDING AT THE GATE IN SEATTLE, THE R AIR CONDITIONING PACK TRIPPED OFF DUE TO A MOMENTARY OVERHEAT. IT WAS WRITTEN UP IN THE ACFT LOGBOOK, AND A MECH SIGNED IT AS A MAINT CARRY-OVER. ON TAXI OUT, WE WERE ABLE TO RESET PACK TO NORMAL OP (FOR BEST SAFETY/REDUNDANCY OF SYS), AND TOOK OFF WITH ALL SYS OPERATING NORMALLY. DURING CRUISE, WE ACCEPTED FL370. HOWEVER, BECAUSE THE PACK WAS TECHNICALLY INOP ON PAPER, THE MEL DISPATCH ALT IS A MAX OF FL350. WE WERE ADVISED OF THIS BY OUR DISPATCHER, AND WE IMMEDIATELY REQUESTED A LOWER ALT OF FL330 FOR THE DURATION OF CRUISE. SAFETY OF FLT WAS NEVER COMPROMISED, BUT THIS IS A TECHNICALITY OF BEING DISPATCHED FOR FLT WITH SOMETHING ORIGINALLY INOP, EVEN THOUGH IT WORKS FOR THE DURATION OF THE DAY.

Data retrieved from NASA's ASRS site as of July 2007 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.