B777-200
Maintenance Airframe; Maintenance Powerplant
Communication Breakdown; Situational Awareness
Aircraft Equipment Problem Critical; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Vehicle
General Maintenance Action
Human Factors
In preparation to move B777-200 aircraft; I installed Steering Bypass Pin and noticed aircraft parking lights on; proceeded to remove chocks; visually checked area and noticed lavatory truck [still] attached to aircraft when Jet Bridge was coming off. The [aircraft] assessment form was not completed as we were waiting for the Lavatory Service truck to complete and move away and right wing man to arrive. Driver told me that aircraft just rolled back and to check and see if the Lavatory Service Technician was O.K.
I was assigned to ride brakes on a B777-200 aircraft parked on Gate. I performed procedures for towing and when the aircraft was fully captured by the Goldhofer [Tug]; I released aircraft brakes.
A B777-200 aircraft suddenly rolled backwards from a terminal gate during preparations for tow. A lavatory truck was still connected to the aircraft.