A300
Flight Crew Last 90 Days 120; Flight Crew Total 9000; Flight Crew Type 1000
Situational Awareness; Distraction; Confusion; Workload; Communication Breakdown
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Loss Of Aircraft Control; Ground Event / Encounter Person / Animal / Bird
Flight Crew Regained Aircraft Control; Flight Crew Took Evasive Action
Human Factors
Aircraft was being push backed while we were starting engines. Pushback stopped for a brief moment then proceeded to tug us forward a little distance. We were starting number one after number two had been started and stable per the AOM. I was looking at the overhead electrical panel for a moment and I heard the Mechanic state '....still hooked up'. Then he said 'You are rolling'. The Captain applied the brakes; set the parking brake and stated he never heard the Mechanic instruct us to set the brakes. Honestly; I never did hear the Mechanic say that either. I asked the Captain to see if the Mechanic was OK. He asked the Mechanic was he OK. Mechanic stated 'I am glad I was not in front of the nose wheel.' Neither I nor the Captain noticed we were rolling forward as we did not expect to be rolling forward and our heads were still in the cockpit regarding engine start procedures. Miscommunication was likely the culprit? I suspect the push- stop- then forward tugging may have been a factor of distraction as we both discussed in the cockpit 'What are they doing?' Mechanic was OK and clear. He checked off the headset and we taxied out for normal flight. In the future; I will pay more attention to the brake set issue before I go to scanning overhead indications to confirm normal situation.
An A300 began rolling after pushback because the Mechanic did not ask the flight crew to set the parking brake before disconnecting the tug and towbar.