Regional Jet 200 ER/LR (CRJ200)
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Time Pressure; Situational Awareness; Distraction
Aircraft Equipment Problem Critical; Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor
Air Traffic Control Issued New Clearance; Air Traffic Control Provided Assistance; Aircraft Aircraft Damaged; Flight Crew Diverted; Flight Crew FLC complied w / Automation / Advisory; Flight Crew Landed in Emergency Condition; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Returned To Departure Airport; Flight Crew Took Evasive Action; General Evacuated
Aircraft
We were climbing through FL200 when the Left Pack seemed to fail (the right pack was currently deferred and inoperative). There was a depressurization followed by an immediate descent to 10;000 ft. Appropriate checklists were run which entailed the passenger oxygen masks would drop down. The decision to return to ZZZ was made shortly after and then unfortunately; fumes and smoke were detected next and a diversion to ZZZ1 was safely executed. Checklists were done appropriately; a [diversion] brief was made; passengers briefed to the situation; and an aircraft deplaning through the main cabin door in a walking manner was made with everyone. An expedited deplaning checklist was run and the aircraft shut down and secured after everyone had left.The cause was suspected to be a remaining PACK failure.This was unexpected and the only thing that may have prevented this was having a shorter time period for the MEL for the R PACK deferral.
[Report narrative contained no additional information.]
CRJ-200 flight crew reported a pack failure that resulted in a cabin decompression and a diversion.