Narrative:

Airplane we were taking arrived at gate xa:25. Our flight was due out at xb:05. The pushback coordinator on the headset called ready for pushback around xb:03. I told him standby. First officer read the before push checklist and called ramp for clearance. Our clearance was received and I released the brake and told coordinator 'brakes released cleared to push.' he acknowledged. My head was down as I was watching the first officer put in our final weights. I looked up and we were slowly moving backward in what seemed like a nice smooth push. All of a sudden I hear coordinator say 'set the brake; set the brake.' I found it difficult to set the brake while we were being pushed back; so I hesitated for a second until I saw the back part of the tug start to appear in my forward window and realized we weren't being pushed at all. I stopped the airplane and set the parking brake. It was a little bit of a jolt but luckily we weren't moving fast enough to injure anyone or tip the airplane on its tail. There seemed to be some confusion among ramp personnel as to why the tow bar came loose. I personally think when I released the brake that the tow bar appeared to be connected but wasn't. Thus we just began to slowly roll back. If in fact it did disconnect during the push; the tug probably only moved a foot or two forward. They reconnected the tow bar properly; we started the pushback protocol over; and completed it normally. I reminded the coordinator that it is imperative you use the term 'breakaway' and not 'set the brakes' if that ever happens again. It was counterintuitive for me to 'set the brakes' while the airplane was in motion during what I thought was a normal pushback.

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Original NASA ASRS Text

Title: A319 Captain reported that during pushback; the tug driver called for brakes set rather than breakaway when the tow bar became disconnected.

Narrative: Airplane we were taking arrived at gate XA:25. Our flight was due out at XB:05. The Pushback coordinator on the headset called ready for pushback around XB:03. I told him standby. FO read the before push checklist and called ramp for clearance. Our clearance was received and I released the brake and told coordinator 'brakes released cleared to push.' He acknowledged. My head was down as I was watching the FO put in our final weights. I looked up and we were slowly moving backward in what seemed like a nice smooth push. All of a sudden I hear coordinator say 'set the brake; set the brake.' I found it difficult to set the brake while we were being pushed back; so I hesitated for a second until I saw the back part of the tug start to appear in my forward window and realized we weren't being pushed at all. I stopped the airplane and set the parking brake. It was a little bit of a jolt but luckily we weren't moving fast enough to injure anyone or tip the airplane on its tail. There seemed to be some confusion among ramp personnel as to why the tow bar came loose. I personally think when I released the brake that the tow bar appeared to be connected but wasn't. Thus we just began to slowly roll back. If in fact it did disconnect during the push; the tug probably only moved a foot or two forward. They reconnected the tow bar properly; we started the pushback protocol over; and completed it normally. I reminded the coordinator that it is imperative you use the term 'breakaway' and not 'set the brakes' if that ever happens again. It was counterintuitive for me to 'set the brakes' while the airplane was in motion during what I thought was a normal pushback.

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.