Narrative:

Pushback tug attempts 4-5 times to contact captain for pushback; carrier only no voice; a lot of static. Three minutes later tug driver loud and clear states having trouble with mic and headset but now hears captain loud and clear. Tug driver states ready for push. Captain states standby. First officer gets push clearance from rampant tells tug driver 'cleared to push disconnect abeam gate C-112.' tug states roger cleared to push disconnect abeam gate C-112. Push initiates and during push captain hears cleared with static and no voice. Three attempts by tug driver carrier only; no voice. Captain then clearly hears cleared to start. Replies cleared to start. Engine 1 started for single engine taxi and captain attempts to contact tug to use hand signal but no reply. We stop abeam C-112 and hear carrier no voice. Marshaller at 12 o'clock position has wands crossed as captain attempts hand signals. Captain hands open points to headset and gives thumbs down and hands wide open. Aircraft starts to move slowly forward; we think we are being towed abeam gate C-112 at which time we see a ramp agent at our 2 o'clock position running across the ramp with his fists closed signaling set brakes! Captain stopped aircraft. Marshaller at 12 o'clock position still standing with wands crossed. Shut down engine 1 and called ramp for a supervisor to hook up to the aircraft to speak to. Supervisor stated tow bar was disconnected and as tug pulled away from the aircraft; the aircraft started to roll toward tug. Aircraft was about 2 feet from tug and towbar and rolled about 10 feet. No damage to aircraft; tug; or personnel because there was no contact.

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Original NASA ASRS Text

Title: An air carrier Captain reported intermittent communications with the pushback crew because of a faulty tug headset so no clear set brake command was heard and after the tow bar was disconnected the aircraft began rolling.

Narrative: Pushback tug attempts 4-5 times to contact Captain for pushback; carrier only no voice; a lot of static. Three minutes later tug driver loud and clear states having trouble with mic and headset but now hears Captain loud and clear. Tug driver states ready for push. Captain states standby. First Officer gets push clearance from rampant tells tug driver 'cleared to push disconnect abeam gate C-112.' Tug states roger cleared to push disconnect abeam gate C-112. Push initiates and during push Captain hears CLEARED with static and no voice. Three attempts by tug driver carrier only; no voice. Captain then clearly hears cleared to start. Replies cleared to start. Engine 1 started for single engine taxi and Captain attempts to contact tug to use hand signal but no reply. We stop abeam C-112 and hear carrier no voice. Marshaller at 12 o'clock position has wands crossed as Captain attempts hand signals. Captain hands open points to headset and gives thumbs down and hands wide open. Aircraft starts to move slowly forward; we think we are being towed abeam gate C-112 at which time we see a ramp agent at our 2 o'clock position running across the ramp with his fists closed signaling set brakes! Captain stopped aircraft. Marshaller at 12 o'clock position still standing with wands crossed. Shut down engine 1 and called Ramp for a Supervisor to hook up to the aircraft to speak to. Supervisor stated tow bar was disconnected and as tug pulled away from the aircraft; the aircraft started to roll toward tug. Aircraft was about 2 feet from tug and towbar and rolled about 10 feet. No damage to aircraft; tug; or personnel because there was no contact.

Data retrieved from NASA's ASRS site as of July 2013 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.