Flight Crew Air Transport Pilot (ATP)
Situational Awareness
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Other / Unknown
Air Traffic Control Issued New Clearance; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Overcame Equipment Problem; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Took Evasive Action
Aircraft
On initial descent cruise at FL270 for arrival; First Officer noticed System Display page Cabin PSI indication was abnormal in red. Immediately; we responded to Cabin PSI system page abnormality. As cabin altitude was showing 9;400 feet and climbing; I commanded oxygen masks on. We asked for immediate descent with ATC and [advised them] of altitude abnormal condition. Flight attendants were already seated and cabin secured as I advised of turbulence and requested early clean up and stay seated. Descent ended at 10;000 feet. Cabin altitude continued to climb over 11;000 feet. Proceeded to airport; and landing uneventful. No deployment of oxygen masks and no injuries or other incidents.
Air carrier Captain reported a malfunctioning pressurization system during descent requiring an immediate descent to a lower altitude.