EMB ERJ 145 ER/LR
Flight Crew Air Transport Pilot (ATP)
Workload; Distraction; Situational Awareness; Time Pressure
Aircraft Equipment Problem Critical
Flight Crew Diverted; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Landed in Emergency Condition; General Declared Emergency
Aircraft
In cruise flight at FL250; there was a sudden 'pop' noise and felt pressurization stop. EICAS indicated PACK 1 Fail. The cabin pressure altimeter started to increase. I had contacted ATC and notified them I needed to descend immediately. ATC responded clear to FL200. I said no; I need 10;000 FT and I was then cleared. We as a crew put on the O2 mask and established crew communication and began our rapid descend ER memory items. As we were descending I had notified the flight attendant of the ER and to prepare the cabin for arrival. She asked if she needs to deploy the passenger O2 masks and after seeing the cabin altitude begin to stabilize and not had gone above 9;800; I said no. I had ACARSed company that we were diverting. ATC told us that airport was just 20 miles behind us and they gave us initial vectors. Once we got down to 10;000 FT; we cleaned the aircraft up (gear up; spoilers stowed) and took our O2 masks off. We then performed normal checklists of weather in range and approach checklist and proceeded to the divert airport. Once cleared to land; we had the Airfield Rescue and Fire Fighters follow us and do a thermal scan of the aircraft for hot spots and check the brakes because of a possible over weight landing. Once given the OK; we taxied to the terminal and debriefed the crew; passengers and company.
An EMB-145 EICAS alerted PACK 1 FAIL; and as the cabin altitude began rising the crew declared an emergency; descended to 10;000 FT; completed the QRH and diverted to a nearby airport.