Narrative:

En route we were at FL450 in order to top weather and provide a smooth ride for passengers. The cabin pressure suddenly began to climb at approximately 1;000 ft per minute. We donned the O2 mask; dropped the mask for our passengers and began a rapid descent to the requested and assigned altitude of FL340. We performed the checklist in accordance with company SOP's and continued the descent to 10;000 ft and then with the company's input; diverted and made a normal landing.

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Original NASA ASRS Text

Title: A CE-560 pressurization failed at FL450 so an immediate descent was begun; an emergency declared; and while navigating around thunderstorms the crew diverted to a nearby airport.

Narrative: En route we were at FL450 in order to top weather and provide a smooth ride for passengers. The cabin pressure suddenly began to climb at approximately 1;000 FT per minute. We donned the O2 mask; dropped the mask for our passengers and began a rapid descent to the requested and assigned altitude of FL340. We performed the checklist in accordance with Company SOP's and continued the descent to 10;000 FT and then with the Company's input; diverted and made a normal landing.

Data retrieved from NASA's ASRS site as of July 2013 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.