Narrative:

Pushback crew did not establish communication with cockpit prior to disconnecting towbar; allowing the aircraft to roll forward. As captain; I did not hear anything from ground crew; except for a garbled transmission which was unreadable. I requested tug crew to 'say again' numerous times with no response. Judging by the sounds from below; I suspected that the tug crew was either attempting to disconnect towbar or pulling aircraft forward. I cycled the taxi light numerous times; as the aircraft was moving forward; at which time tug crew person came back on with 'set brakes;' which I did. With no further communication from tug crew; towbar and headset were disconnected; and salute and release were offered off the right side of the aircraft. I notified ramp control of the non-SOP procedure; and departed the area.

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Original NASA ASRS Text

Title: B757-200 CAPTAIN REPORTS NONSTANDARD COMMUNICATIONS WITH GROUND CREW DURING PUSH BACK RESULTING IN ACFT ROLLING FORWARD.

Narrative: PUSHBACK CREW DID NOT ESTABLISH COM WITH COCKPIT PRIOR TO DISCONNECTING TOWBAR; ALLOWING THE ACFT TO ROLL FORWARD. AS CAPT; I DID NOT HEAR ANYTHING FROM GND CREW; EXCEPT FOR A GARBLED XMISSION WHICH WAS UNREADABLE. I REQUESTED TUG CREW TO 'SAY AGAIN' NUMEROUS TIMES WITH NO RESPONSE. JUDGING BY THE SOUNDS FROM BELOW; I SUSPECTED THAT THE TUG CREW WAS EITHER ATTEMPTING TO DISCONNECT TOWBAR OR PULLING ACFT FORWARD. I CYCLED THE TAXI LIGHT NUMEROUS TIMES; AS THE ACFT WAS MOVING FORWARD; AT WHICH TIME TUG CREW PERSON CAME BACK ON WITH 'SET BRAKES;' WHICH I DID. WITH NO FURTHER COM FROM TUG CREW; TOWBAR AND HEADSET WERE DISCONNECTED; AND SALUTE AND RELEASE WERE OFFERED OFF THE R SIDE OF THE ACFT. I NOTIFIED RAMP CTL OF THE NON-SOP PROC; AND DEPARTED THE AREA.

Data retrieved from NASA's ASRS site as of January 2009 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.