Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Flight Crew Total 4500
Troubleshooting; Communication Breakdown
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
Flight Crew Overcame Equipment Problem
Aircraft
While operating flight [from] PHL; while in cruise flight at 36;000 feet MSL; we noticed an abnormally cold temperature in the cockpit. We turned up the Pack 1 temperature and noted the flight deck temperature got even colder. It was indicating 18 [degrees] Celsius and after increasing the temperature more. It continued to drop to 16 [degrees] Celsius. It was so cold; we noticed frost beginning to form on the inside of the unheated portion of the windshield. Around this time; we noticed the EICAS cabin altitude was indicating 7;700 feet ALT and 7.7 PSID and still indicating green while a small climb of 100 FPM on the cabin rate of climb. After a few moments; it was indicating amber around 8;400 feet and still climbing. We started discussing pressurization problems and the need to descend. We notified ATC and requested a descent to a lower altitude. ATC gave us 24;000 MSL at first. We began to run the QRH for Cabin Rate Abnormal Fluctuations and notified the Flight Attendant to take her seat. We noted that the cabin altitude became green again with lower values once passing through FL200. We took control of the cabin pressurization in manual mode and followed NAP-30 as directed by the QRH to achieve normal cabin pressure values. We notified ATC of an abnormal cabin pressure event and that we were continuing to [destination airport]. We texted Dispatch about our cabin pressurization problem and that the fuel state and weather looked good enough to continue. We got no response from Dispatch. We notified our Flight Attendant that everything was normal again and she could get up to do her final walk through. We completed our normal descent and landing checklists and landed normally with the pressurization in manual mode.Self scan; vigilance. and situational awareness.Pack 1 unable to heat cockpit and pressurize aircraft sufficiently at aircraft altitude 36;000 feet MSL. There were no EICAS messages of a pack failure or any other abnormal indications except the Amber high cabin altitude on the EICAS. Took action to stop the cabin from climbing and depressurizing. Ran QRH; notified ATC notified Flight Attendant; took manual control of cabin pressurization; and landed safely at our planned destination. We also notified company Dispatch via ACARS with 2 messages and got no response.Thankfully we had good weather and were tankering a lot of fuel. Had the weather been marginal and the fuel state less than desirable; we would have been much more task saturated determining an alternate course of action especially because dispatch did not respond to our messages.
Flying along at FL360; [we] noticed that we were cold; turning the pack one up to keep us warm and the temp got even colder. Troubleshoot the pack with no effect. Ice was present on the INSIDE of the unheated area on the windscreen. No EICAS or system abnormal indications. We noticed cabin altitude was 7;700 feet with a climb of 100 feet/minute and we started discussing cabin pressurization and the apparent pack issue. The Captain pulled out the QRH and referenced the cabin altitude tables; we discovered the ideal value was 7;600 feet and 7.7 PSI. Cabin altitude went to amber at 8;400 feet with a constant 100 feet/minute climb. We requested descent and was cleared to FL240 initially; then 11;000 feet after a few minutes. The Captain ran the 'Cabin Rate Abnormal Fluctuations' QRH which we completed resulting in the indications stabilizing and the cabin altitude indication returning to green status. We leveled at 11;000 feet and after a discussion with the Flight Attendant and ourselves; we elected to continue to [destination airport]. The Captain notified the company dispatcher via ACARS of our situation and we landed with a normal landing and deplaned. On the phone to the Dispatch after the flight; the Captain was made aware that the Dispatcher had not even read our messages and was not aware we're flying at such a low altitude or that we had issues with the pressurization. We had looked at the fuel plan and amount of fuel in the tanks; the weather at [destination airport] and had already decided to continue; which was also sent to the Dispatcher; but we never got any response.
Air carrier flight crew noticed an issue with pressurization during cruise flight. The PACK was unable to maintain cabin altitude nor temperature. The crew followed the QRH; made a descent to a lower altitude; and continued to their original destination.