CE-750 flight crew reported Cabin Pack Over Temp in cruise flight. Flight crew performed a diversion and uneventful landing.
Synopsis
CE-750 flight crew reported Cabin Pack Over Temp in cruise flight. Flight crew performed a diversion and uneventful landing.
Narrative
Approximately 40 minutes after takeoff from ZZZ; shortly after level-off and cruise check at FL450; observed COCKPIT PAC O'TEMP Caution Crew Alert System (CAS) message (Note: when this happens; PAC will automatically shut down); performed checklist items; CAS message disappeared; approximately 2 minutes later; same message appeared; while referring to checklist again; CABIN PAC O'TEMP Caution CAS message illuminated; we could immediately sense increase in cabin altitude; I glanced at cabin altitude gage and noted rapid increase; I could also sense physiological change (thank you all those altitude chamber flights); we immediately donned oxygen masks; I took control of the aircraft and asked my crewmate to [request a priority landing] and inform ATC we were diverting to ZZZ1; we had just passed ZZZ1 and made a right turn toward the airport while doing an emergency descent; I manually deployed cabin oxygen masks for passengers; cabin altitude reached over 14000 ft. (CABIN ALTITUDE Warning CAS); ZZZ1 is my home airport and I am very familiar; we had the airport in sight and were cleared for a visual approach on Runway XX; which is 13;000 long; visual approach and landing were uneventful; we were a bit heavy; with 8200 pounds of fuel; but extremely long runway negated any risk/problem with landing; escorted passengers into FBO while thoroughly explaining what had happened; passengers were quite calm and understanding; very fortunate that it was beautiful weather and familiar airport; all in all; the best that could happen with a potentially serious event.
Second reporter narrative
At FL 450 got a cockpit pack over temp Message. Ran checklist and message cleared. A few minutes later got same cockpit over temp message. While running the checklist for that; we got a cabin pack over temp message. The resulting shutdown of the second pack sent the cabin altitude climbing. We immediately went on oxygen; [requested landing priority] the Captain took control of the aircraft and began a priority descent. The cabin oxygen masks were deployed and during the descent; the cabin altitude reached 14000 ft. We got an ATC clearance to descend and a turn to ZZZ1 due to its proximity and its familiarity to the Captain. Accomplished an uneventful visual approach and landing in ZZZ1. Passengers were calm and understanding. Got the passengers comfortable in the terminal and then took care of the maintenance write-ups.
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.