Narrative:

While cruising at our certified service ceiling altitude of FL410, the chief pilot, flying sic and myself, were vectoring around thunderstorm build-ups. I left my seat momentarily and when I had returned, I noticed that the chief pilot, without my knowledge, had climbed the aircraft above it's certified service altitude. I promptly descended the aircraft back down to FL410 when I became aware of his actions. He said he did it because we could get a 'better ride' higher up.

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Original NASA ASRS Text

Title: A CPR JET FLT IS TEMPORARILY FLOWN ABOVE ITS CERTIFIED CEILING BY THE CHIEF PLT FO WHEN NEAR TURB NEAR TSTM ACTIVITY 100 MI ESE OF CVG, KY.

Narrative: WHILE CRUISING AT OUR CERTIFIED SVC CEILING ALT OF FL410, THE CHIEF PLT, FLYING SIC AND MYSELF, WERE VECTORING AROUND TSTM BUILD-UPS. I LEFT MY SEAT MOMENTARILY AND WHEN I HAD RETURNED, I NOTICED THAT THE CHIEF PLT, WITHOUT MY KNOWLEDGE, HAD CLBED THE ACFT ABOVE IT'S CERTIFIED SVC ALT. I PROMPTLY DSNDED THE ACFT BACK DOWN TO FL410 WHEN I BECAME AWARE OF HIS ACTIONS. HE SAID HE DID IT BECAUSE WE COULD GET A 'BETTER RIDE' HIGHER UP.

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.