Regional Jet 200 ER/LR (CRJ200)
Flight Crew Multiengine; Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP)
Training / Qualification; Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown; Ground Excursion Taxiway
Aircraft Aircraft Damaged; General Maintenance Action; General Flight Cancelled / Delayed
Human Factors; Airport
There was ground delay program and ground stop into ORD. The crew stayed at the gate as much as possible to minimize the time for the passengers on the aircraft sitting outside the runway. Right before the first tier of ground stop was about to expire at 00:00Z; passengers began to board and crew prepared for the flight. After block out from the gate and while taxiing to the runway for departure; ATC (Air Traffic Control) updated estimated departure clearance time to 00:30Z. Crew decided to hold short of runway 36 on the taxiway D with the slope and had permission from ATC to shutdown engines. Parking brake was set and APU (Auxiliary Power Unit) was still running; but turned hydraulic pump 3A off; leading to the situation that parking brake lost pressure and airplane started to roll back outside taxiway and both right and left main gears fall into the grass area. While rolling back into the grass; crew attempted to restart the engines to prevent rolling back but it was too late to stop the airplane. No damage on airplane was found except the right main gear door was bent. ORD ground stop and delay program led the crew to shutdown engines; and crew made a mistake to turn the hydraulic pump 3A off.Always keep the hydraulic pump 3A on when shutting down the engines anywhere besides gate or chocks are in.
[Report narrative contained no additional information.]
CRJ-200 flight crew reported a taxiway excursion while holding for takeoff.