Air carrier flight crew reported the aircraft rolled over the tow bar after push back from the gate when there was confusion between ramp personnel and the cockpit. SOPs were not followed.
Synopsis
Air carrier flight crew reported the aircraft rolled over the tow bar after push back from the gate when there was confusion between ramp personnel and the cockpit. SOPs were not followed.
Narrative
After pushback; crew had set parking brake per push crews order. Push crew tried numerous times to unhook tow bar from aircraft unsuccessfully. Push crew asked me to release the parking brake while he fixed the tow bar. He stated it was at an angle. We were expecting him to either tug us forward or backward to straighten the bar; however he unhooked the tow bar without telling us to set the parking brake causing the aircraft; that had both engines running; to move forward slightly causing both nose tires to ride up over the tow bar. Maintenance then changed both nose tires. Tug operator was not Maintenance personnel; but a ramper. Tug operator originally pushed us out of the gate and to a stop halfway between the ramp centerline and the outer foul line. I was concerned I could contact my wing on the tail of the aircraft parked next us when I started taxiing. When he asked me to set brakes I then asked him to tug us to the centerline. He then proceeded to tug us forward to the line. Then the above started.Cause: Tug crews failure to follow standards. Suggestions: Tug operator following standard procedure and not disconnecting tow bar without telling crew to set parking brake.
Second reporter narrative
The ramp employee began the standard push back procedure from gate. Upon stopping; we noticed that the aircraft was at least 50 ft right of center line. The Captain informed the ramp employee of this and he began to pull us forward on center line. We then set our parking brake per SOP and the employee started trying to disconnect the tow bar. After 4 minutes of struggling; he asked us to release the parking brake so he could try to straighten the nose wheel; and we complied. About a minute later; we felt the aircraft move forward (both engines running prior) and felt our aircraft run over something and heard a loud crunch". The ramp employee; in horror; told us to "Set brake; set brake!" As our aircraft had run over the tow bar. Cause: The first cause of this event is the outsourcing of push back duties from experienced maintenance personnel to unseasoned ramp employees to increase (short term) profit on the company income statement. The second cause is the lack of training given to said ramp employees to perform SOPs at a safe and efficient level. Suggestions: This event could (and will) be prevented upon returning push back duties to experienced maintenance personnel whom understand company SOPs and best safety practices."
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.