Citation Latitude (C680A)
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Other / Unknown; Inflight Event / Encounter Weather / Turbulence
Flight Crew Landed in Emergency Condition; Flight Crew Diverted
Aircraft
Enroute at FL410; we lost pressurization and executed an emergency descent and diverted to ZZZ. The first CAS message we had was a Pressurization FAULT CAS message. Checklist calls for select Manual then Auto. If message remains select Manual. The light went out momentarily then came right back on; so we selected Manual. During this process the GEA FAIL 3 CASS message came on and the cabin started immediately dumping cabin pressure rapidly and we executed an emergency descent. During the descent the Engine Control FAULT R and CABIN ALT red CASS messages came on. We ran the GEA FAIL 3 checklist next which says select Manual Pressurization. However; the temporary revision checklist TC-R02-03 in step 2 states that cabin pressurization will dump when selected to Manual. I read the revision in the IPad after the event occurred. In Auto or Manual the cabin was losing pressurization. I believe at some point in the descent; I selected Auto to see if that would help because Manual wasn't helping. Auto also allowed for the cabin O2 mask to automatically deploy. Also with the GEA FAIL 3; we would not have indication of our right main landing gear down along with other failed indicators which led us to blow down the landing gear. On final going into ZZZ with strong headwinds the wind shear warning was sounding but the airplane and airspeed seemed stable; so I decided to land under the circumstances.I think the Pressurization FAULT Checklist needs to have a warning that if GEA FAIL 3 is displayed the cabin will dump in Manual. The cabin was losing Pressurization in Auto initially but really started dumping at a rapid rate in Manual with the GEA FAIL 3. If you have the Pressurization FAULT CASS message along with the GEA FAIL 3 and you're losing Pressurization; I believe there needs to be better checklist guidance. Pressurization FAULT leads you to Manual Pressurization. GEA FAIL 3 leads to cabin dumping in Manual Pressurization.
Citation flight crew encountered loss of pressurization inflight.