Narrative:

Operating aircraft during a loss of both packs and running the 'pressurization - unpressurized flight procedure'. We received aircraft X with the right pack MEL'd. After extensively reviewing the MEL procedures for safe operation we taxied out to begin our short trip. During departure from runway 1 ZZZ at 5000 feet when switching the bleeds from the APU to the engines we lost the left pack due to an 'left pack hi press' caution message. I began running the 'pack hi press (left/right) amber message' QRH procedures and the pack would not reset. The captain transferred flight controls and radios to me to further diagnose the problem and procedures. After a few minutes we discussed climbing to 10;000 and requested higher from ATC. During our climb to 10;000 feet the cabin pressure began climb and eventually surpass our actual altitude (altimeter 7800 feet / cabin 8;200 feet and increasing); so we requested to descend and remain at 6;000 feet. The captain ran through the hi press procedures a couple of times in an attempt to reset our only available pack; with no luck and thus; led us to the 'pressurization - unpressurized flight procedure'. While performing the unpressurized flight procedure steps; the captain read to me; 'altitude...maximum 10;000 feet or lowest safe altitude'...I acknowledged. Then he read; 'cruise airspeed....not less than 250 KIAS'...I acknowledged. He continued with the remaining 6 steps and I acknowledged accordingly. When I heard 'not less than 250 KIAS' I sped up to 270-280 KIAS; completely ignoring/forgetting the 250 KIAS speed limit below 10;000 feet. A minute or two passed and the captain performed an instrument scan and informed me of my error. We slowed to 250 KIAS and continued to our destination without further incident.

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Original NASA ASRS Text

Title: Bombardier CRJ-200 First Officer reported a speed deviation following the failure of the pressurization system that necessitated an altitude below 10;000 feet.

Narrative: Operating aircraft during a loss of both packs and running the 'Pressurization - Unpressurized Flight Procedure'. We received Aircraft X with the right pack MEL'd. After extensively reviewing the MEL procedures for safe operation we taxied out to begin our short trip. During departure from Runway 1 ZZZ at 5000 feet when switching the bleeds from the APU to the engines we lost the left pack due to an 'L Pack Hi Press' caution message. I began running the 'PACK HI PRESS (L/R) Amber Message' QRH procedures and the pack would not reset. The captain transferred flight controls and radios to me to further diagnose the problem and procedures. After a few minutes we discussed climbing to 10;000 and requested higher from ATC. During our climb to 10;000 feet the cabin pressure began climb and eventually surpass our actual altitude (altimeter 7800 feet / cabin 8;200 feet and increasing); so we requested to descend and remain at 6;000 feet. The captain ran through the Hi Press procedures a couple of times in an attempt to reset our only available pack; with no luck and thus; led us to the 'Pressurization - Unpressurized Flight Procedure'. While performing the unpressurized flight procedure steps; the captain read to me; 'Altitude...Maximum 10;000 feet or lowest safe altitude'...I acknowledged. Then he read; 'Cruise airspeed....Not less than 250 KIAS'...I acknowledged. He continued with the remaining 6 steps and I acknowledged accordingly. When I heard 'Not less than 250 KIAS' I sped up to 270-280 KIAS; completely ignoring/forgetting the 250 KIAS speed limit below 10;000 feet. A minute or two passed and the captain performed an instrument scan and informed me of my error. We slowed to 250 KIAS and continued to our destination without further incident.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.