Narrative:

Was the fb on flight abc, ZZZ to ZZZ1. While at the gate, the ground crew tried to motion to the captain that they had no headset for engine start and that they wanted to use hand signals. The captain refused and told them to find an operative headset. After some search, ground crew returns and says he has one that he things will work. As we push back, he clears us to start. The autostart function on the left engine fails almost immediately as we attempt to start both engines simultaneously. We notify the ground personnel of this and tell him to not disconnect because we have a problem. He says fine. About this time we have finished our pushback and are still connected to the tug. We refer to the manual engine start checklist and the left engine starts normally. At this time, we notify the ground personnel that we have 2 normal starts and that he is cleared to disconnect. He replied he'd see us out front. The next thing we realize is that the airplane is rolling forward and that the ground crew had in fact disconnected the tug without ever telling us to set the parking brake. Although nothing occurred, there was a tremendous opportunity for an accident to happen, to either the ground personnel or the aircraft should have contacted either the ground personnel or the tug, as the aircraft rolled forward.

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Original NASA ASRS Text

Title: A B777 AFTER ENG START AND WITH NO GND TO COCKPIT COM THE GND CREW DISCONNECTED THE TUG AND TOWBAR. THE AIRPLANE ROLLED FORWARD ENDANGERING THE GND CREW.

Narrative: WAS THE FB ON FLT ABC, ZZZ TO ZZZ1. WHILE AT THE GATE, THE GND CREW TRIED TO MOTION TO THE CAPT THAT THEY HAD NO HEADSET FOR ENG START AND THAT THEY WANTED TO USE HAND SIGNALS. THE CAPT REFUSED AND TOLD THEM TO FIND AN OPERATIVE HEADSET. AFTER SOME SEARCH, GND CREW RETURNS AND SAYS HE HAS ONE THAT HE THINGS WILL WORK. AS WE PUSH BACK, HE CLRS US TO START. THE AUTOSTART FUNCTION ON THE L ENG FAILS ALMOST IMMEDIATELY AS WE ATTEMPT TO START BOTH ENGS SIMULTANEOUSLY. WE NOTIFY THE GND PERSONNEL OF THIS AND TELL HIM TO NOT DISCONNECT BECAUSE WE HAVE A PROB. HE SAYS FINE. ABOUT THIS TIME WE HAVE FINISHED OUR PUSHBACK AND ARE STILL CONNECTED TO THE TUG. WE REFER TO THE MANUAL ENG START CHKLIST AND THE L ENG STARTS NORMALLY. AT THIS TIME, WE NOTIFY THE GND PERSONNEL THAT WE HAVE 2 NORMAL STARTS AND THAT HE IS CLRED TO DISCONNECT. HE REPLIED HE'D SEE US OUT FRONT. THE NEXT THING WE REALIZE IS THAT THE AIRPLANE IS ROLLING FORWARD AND THAT THE GND CREW HAD IN FACT DISCONNECTED THE TUG WITHOUT EVER TELLING US TO SET THE PARKING BRAKE. ALTHOUGH NOTHING OCCURRED, THERE WAS A TREMENDOUS OPPORTUNITY FOR AN ACCIDENT TO HAPPEN, TO EITHER THE GND PERSONNEL OR THE ACFT SHOULD HAVE CONTACTED EITHER THE GND PERSONNEL OR THE TUG, AS THE ACFT ROLLED FORWARD.

Data retrieved from NASA's ASRS site as of July 2007 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.