What happened
The ground controller (GC) coordinated with the local controller (LC) and cleared a B-747 to cross Runway 12 via taxiway V. At the time, an MD-11 had landed on Runway 9R and was holding short of Runway 12 at the intersection of taxiways V and S, maintaining contact with the LC.
The B-7CO flightcrew notified the GC that the MD-11 was obstructing the opposite side of the runway. The GC did not acknowledge this report and reissued the clearance for the B-747 to cross the runway. As the B-747 proceeded, it stopped short of the MD-11, but the tail of the aircraft remained over the edge of Runway 12.
The LC then asked the MD-11 if it could execute a right turn onto taxiway S. The MD-11 flightcrew acknowledged this as a clearance and began the turn. Upon seeing the MD-11 begin to move, the captain of the B-747 transmitted on the ground control frequency instructing the pilot to stop; however, the MD-11 was operating on the local control frequency.
In an attempt to avoid the B-747, the MD-11 captain steered the aircraft to the far right side of the taxiway, causing the right main landing gear to strike two taxiway lights. During this maneuver, the left wingtip of the MD-11 struck the nose of the B-747. Simultaneously, the GC instructed the B-747 to pull forward because its tail was obstructing Runway 12 and other traffic was landing. As the B-747 moved forward, the left wingtip of the MD-11 collided with the left wing of the B-747. The incoming landing traffic included a heavy aircraft that had landed while the B-747 had not yet fully cleared the runway holding line.