PC-12
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor
Flight Crew Last 90 Days 100; Flight Crew Total 5000; Flight Crew Type 650
Aircraft Equipment Problem Less Severe
Flight Crew Diverted; Flight Crew Took Evasive Action; Flight Crew Landed As Precaution
Aircraft
Climbing through FL210 we received a caution for part of our pressurization system. We completed the checklist which momentarily cleared the malfunction. Seconds later it returned with a decompression with the cabin rate climbing about 1;700-2;000 FPM. My first officer; our passengers and I put on our oxygen masks and I completed an emergency descent. [I advised ATC] and I elected to divert to the closest airport. No further issues occurred; no limitations aside from differential pressure were exceeded.
PC12 Captain reported diverting to a nearby alternate after a loss of cabin pressure.