What happened
An aircraft collision occurred on taxiway Charlie involving a WLAC-1 and an Aero Commander. The WLAC-1 had been cleared to proceed westbound on taxiway Charlie. Simultaneously, the Aero Commander was cleared to taxi on the same taxiway and was in the process of entering the taxiway from the ramp area.
As the Aero Commander moved onto the taxiway, the two aircraft converged on a shared path, resulting in a collision. Neither pilot reported observing the other aircraft until the moments immediately preceding the impact.
Findings
An examination of air traffic control tower tape transcripts confirmed that both pilots had received and acknowledged their respective taxi clearances. However, the investigation determined that neither pilot had been issued traffic advisories regarding the taxi routes of the other aircraft.
It was noted that the specific section of taxiway Charlie where the collision took place had been redesignated as a ramp area in 1986. Under the guidelines of FAA Air Traffic Control Handbook 7110.65, non-movement areas, such as ramps, are not under the jurisdiction of the tower. Per this handbook, the responsibility for maintaining collision avoidance within non-movement areas rests with the pilot.