Narrative:

We were pushing back; communications were established and ops were normal. We had been cleared to start and had started the number 2 engine. At one point the pushback stopped; a bit sooner than I expected. I assumed there must be something blocking our path. After a short delay and not hearing from the tug driver I tried numerous times to contact the driver. I got no response from him. I noticed the aircraft moving forward; leaned forward to see that the tug was not moving (not towing us) and went for the brakes. However; it was too late and I felt a small impact. I set the brakes. I opened the flight deck window and attempted to talk to the ground crew. Communication was difficult. There seemed to be a language barrier and the tug driver's headset was malfunctioning. I think it might have been a bluetooth headset. After several minutes of trying I was finally able to talk to the driver on the headset. I told him that we struck something. I told the driver that we would need to be towed back to the gate for a maintenance inspection. I thought I was quite clear. Instead the driver disconnected the headset and drove away. The marshaller attempted to give me a salute as I was shaking my head 'no.' I did not flash my light to accept the salute but the marshaller just walked away. I had the first officer shut down the number 2 engine and inform the ramp tower that we needed a tow back to the gate for maintenance inspection. It took quite some time to get another crew out there. In the mean time we called maintenance and I entered the need for an inspection in the log. No damage was found; the inspection was signed off and we departed again. Failure of the tug driver to follow standard operating procedures after a failure of the tug driver's headset. No attempt was made to substitute hand signals after a failure of the headset to assure brakes were set. Emphasize the importance of standard operating procedures to ground crews.

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Original NASA ASRS Text

Title: B737 Captain reported the aircraft rolled forward after push back and a small bump was felt before the brakes could be set. The ground crew attempted to release the aircraft over the Captain's request for maintenance inspection.

Narrative: We were pushing back; communications were established and ops were normal. We had been cleared to start and had started the number 2 engine. At one point the pushback stopped; a bit sooner than I expected. I assumed there must be something blocking our path. After a short delay and not hearing from the tug driver I tried numerous times to contact the driver. I got no response from him. I noticed the aircraft moving forward; leaned forward to see that the tug was not moving (not towing us) and went for the brakes. However; it was too late and I felt a small impact. I set the brakes. I opened the flight deck window and attempted to talk to the ground crew. Communication was difficult. There seemed to be a language barrier and the tug driver's headset was malfunctioning. I think it might have been a Bluetooth headset. After several minutes of trying I was finally able to talk to the driver on the headset. I told him that we struck something. I told the driver that we would need to be towed back to the gate for a maintenance inspection. I thought I was quite clear. Instead the driver disconnected the headset and drove away. The marshaller attempted to give me a salute as I was shaking my head 'no.' I did not flash my light to accept the salute but the marshaller just walked away. I had the First Officer shut down the number 2 engine and inform the ramp tower that we needed a tow back to the gate for maintenance inspection. It took quite some time to get another crew out there. In the mean time we called maintenance and I entered the need for an inspection in the Log. No damage was found; the inspection was signed off and we departed again. Failure of the tug driver to follow standard operating procedures after a failure of the tug driver's headset. No attempt was made to substitute hand signals after a failure of the headset to assure brakes were set. Emphasize the importance of standard operating procedures to ground crews.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.