Falcon 900
Flight Crew Air Transport Pilot (ATP); Flight Crew Flight Instructor
Flight Crew Last 90 Days 35; Flight Crew Total 3600; Flight Crew Type 750
Troubleshooting
Aircraft Equipment Problem Less Severe
Air Traffic Control Provided Assistance; Flight Crew Landed in Emergency Condition; Flight Crew Diverted
Aircraft
We were on a flight cruising at FL410 when we noticed some things with pressurization weren't adding up. Climbing up to 410 and still in 30's; we noticed air in gaspers were very weak which grew concern between the other pilot and myself. After discussing the problem; we decided to request a lower altitude in the 30's in case we did lose pressurization; we could have more time to react especially with passengers on board. Both of us pulled our oxygen masks out and had them in our lap; and we watched the automatic pressure controller start to make some changes in differential pressure dropping slowly and cabin altitude slowly climbing. At this time; the cabin warning came on the annunciator panel and followed the cabin warning checklist. The automatic pressure controller started to change with triple indicators; and we both decided to [request priority handling] especially for our passenger's sake. ATC helped us descend our altitude and get us diverted to [nearby] airport safely.As we got lower; the cabin warning went off and we were at a low enough altitude to remove our oxygen masks. [Company maintenance] diagnosed the situation; and it turned out the flex tube that connects to forward part of water separator became disconnected which kept the bleed air from going to the cabin and pressurizing the airplane.
[Report narrative contained no additional information.]
Flight crew Falcon 900 reported a failure of cabin pressurization and commenced an emergency descent and diverted to a nearby airport.