MD-11
Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Communication Breakdown; Situational Awareness
Conflict Ground Conflict; Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown
Flight Crew Took Evasive Action
Human Factors
External air needed for start. Had minor display problem on air synoptic requiring discussion with Maintenance. Problem fixed and continued with start. Tug was not visible after start; but thought to be attached to aircraft. Completing External Air Start Checklist; felt aircraft moving forward. Immediately stopped aircraft. Asked [Ramp] on intercom if tug was pulling aircraft forward. No one on com. Tug was not hooked to aircraft. Someone pulled chocks after external start. I believe normal checklist flow with Maintenance due to display problem had the effect of disrupting procedure. Distraction. Abnormal events during air start procedure. Slow down. Insure standard phraseology used.
MD-11 Captain reported ground personnel pulled the chocks without coordination with the cockpit and the aircraft rolled forward before the Captain applied brakes; endangering ground personnel and equipment.