EMB ERJ 170/175 ER/LR
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Communication Breakdown; Distraction; Situational Awareness; Time Pressure
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Loss Of Aircraft Control
Flight Crew Regained Aircraft Control
Human Factors
Parking brake was not set. Rolled back 5 ft. Captain noticed we were rolling back and set the parking brake. We pulled up to the gate. I grabbed the checklist to start the shutdown checklist. I stated 'parking-brake' 3 times. With no reply. During the event I was focused on the checklist. I stated parking brake 3 times with no reaction from the Captain. Rather than being focused on finishing the checklist I am much more aware of my surroundings. Keeping my head outside the cockpit until the parking brake comes on.
EMB-175 First Officer reported failure to set parking brake at gate.