A B787 flight crew reported transiting china and approaching korea with imminent weather was restric...

Attributes
ACN	1340961
Time
Date	201603
Local Time Of Day	1801-2400
Place
Locale Reference	ZZZZ.Airport
State Reference	FO
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	Widebody Low Wing 2 Turbojet Eng
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Air Conditioning Compressor
Person 1
Function	Captain Pilot Flying
Experience	Flight Crew Last 90 Days 240 Flight Crew Total 24000 Flight Crew Type 810
Person 2
Function	First Officer Pilot Not Flying
Experience	Flight Crew Total 7291 Flight Crew Type 685
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural Published Material / Policy Deviation - Procedural FAR Deviation - Procedural MEL Inflight Event / Encounter Weather / Turbulence

Narrative:

We [were] dispatched in an aircraft that had two placards: MEL's limiting the aircraft to fl 350 due to L1 cabin air compressor. Enroute we were assigned FL350 which put us barely above thunderstorms. We received from dispatch a report for moderate turbulence from fl 290-340; and aircraft lower than us were complaining of bad rides; including moderate turbulence.we were then given the choice of FL310 or FL390 to pass zzzzs ADIZ. Anything lower than our altitude would have put us in immediate danger of embedded thunderstorms; with no clear and safe deviation path around them. For safety reasons we elected to climb to FL390 for a short time; thereby exceeding maximum placarded altitude of 350. Upon clearing the thunderstorms we descended back to FL350. We had a safe and smooth ride; and no reports of any abnormal conditions in the crew rest areas.

Original NASA ASRS Text

Title: A B787 flight crew reported transiting China and approaching Korea with imminent weather was restricted to FL350 because a cabin pressurization compressor was MELd. The crew elected to temporarily climb to FL390 over the weather.

Narrative: We [were] dispatched in an aircraft that had two placards: MEL's limiting the aircraft to FL 350 due to L1 Cabin Air Compressor. Enroute we were assigned FL350 which put us barely above thunderstorms. We received from dispatch a report for moderate turbulence from FL 290-340; and aircraft lower than us were complaining of bad rides; including moderate turbulence.We were then given the choice of FL310 or FL390 to pass ZZZZs ADIZ. Anything lower than our altitude would have put us in immediate danger of embedded thunderstorms; with no clear and safe deviation path around them. For safety reasons we elected to climb to FL390 for a short time; thereby exceeding maximum placarded altitude of 350. Upon clearing the thunderstorms we descended back to FL350. We had a safe and smooth ride; and no reports of any abnormal conditions in the crew rest areas.

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.

A B787 flight crew reported transiting china and approaching korea with imminent weather was restricted to FL350 because a cabin pressurization compressor was meld. The crew elected to temporarily climb to FL390 over the weather.