A320
Flight Crew Air Transport Pilot (ATP)
Communication Breakdown; Training / Qualification
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown
Flight Crew Regained Aircraft Control; Flight Crew Became Reoriented
Human Factors; Aircraft
During pushback ground crew asked me to set parking brake. I complied. They had difficulty releasing the tow bar and asked me to release the parking brake. I did not and told them SOP dictates that I don't. They then told me that they wanted to push me back further to put the tow bar in better position and asked that I release the brake for further push. I complied and they pushed the aircraft back just slightly and stopped. He had a hot mike and I asked him if I could set the brakes.  He said no and I heard him working with the tow bar on hot mike. The aircraft then jerked as he released the tow bar with the brakes not set. He said 'set the brakes' three times very quickly as the aircraft slowly creeped forward. I complied and the aircraft stopped. He disconnected without asking; moved away from the aircraft and the other ramp worker gave me the okay to taxi signal. I flashed the taxi light and they left. Upon running the after start checklist we realized the nose wheel steering disconnect message was still present in Amber. The ground crew had realized their mistake at about the same time and approached the aircraft with our concurrence to flip the nose wheel steering switch. This was accomplished and we safely taxied away.
An A320 Captain reported that a ground crew used improper procedures during the towbar disconnect; which resulted in the aircraft rolling with men and equipment under the aircraft and the nosewheel steering having not been switched back on by the ground crew.