On May 23, 1995, at 1215 Pacific daylight time, an Aero Commander 500S, N9076N, collided with an experimental WLAC-1, N101WL, while both aircraft were taxiing at Santa Barbara, California, airport. The Aero Commander was owned and operated by Commandair and was departing on an aerial observation mission. The experimental WLAC-1 was owned and operated by the pilot and was preparing to depart on a personal flight. Visual meteorological conditions prevailed and neither aircraft had filed a flight plan for their respective operations. Neither the certificated airline transport pilot of the Aero Commander nor the certificated private pilot of the WLAC-1 was injured; however, the sole passenger onboard the Aero Commander sustained serious injuries. According to statements made by air traffic controllers at the airport, both aircraft had received clearances to taxi, but neither had been given traffic advisories regarding each others taxi routes. The WLAC-1 was cleared to taxi westbound on taxiway Charlie en route to Pacific Aviation. The WLAC-1 had been instructed to hold short of runway 15L. The Aero Commander was cleared to taxi to runway 15L via taxiway Charlie. According to the pilot of the Aero Commancer he was in the process of turning right to reverse direction and entering taxiway Charlie southwest bound from the Santa Barbara Aviation ramp. As the pilot of the Aero Commander began to merge onto taxiway Charlie, his path crossed in front of the oncoming WLAC-1. Both aircraft converged on approximately a 45-degree angle. As the aircraft made contact the left wing of the Aero Commander struck the right wing of the WLAC-1, spinning that aircraft nearly 180 degrees in a clockwise direction. During that process the WLAC-1's propeller struck the Aero Commander in the area of the left pilot's door. The pilot of the Aero Commander was seated in the right seat. He stated that after receiving a taxi clearance, he approached taxiway Charlie, and looked both left and right for vehicles and aircraft. Not seeing any traffic, he started a turn to the right (west). As he entered taxiway Charlie, his aircraft was struck by another aircraft approaching from his left rear. The pilot of the WLAC-1 reported that after receiving a taxi clearance, he was taxiing at the speed of a brisk walk when the Aero Commander appeared rapidly from his right rear blind spot. Upon seeing the aircraft approaching from his right, he attempted to swerve left but was unable to avoid a collision due to the proximity and closure rate of the other aircraft. A review of air traffic control tower (ATCT) tape transcripts verified that both pilots had been given and acknowledged taxi clearances. However, the portion of taxiway Charlie (east of taxiway Juliet) where the collision occurred was redesignated a ramp area on August 11, 1986, by the Santa Barbara Airport Director. According to FAA Air Traffic Control specialists, non-movement areas are not under the control of the ATCT. The responsibility for collision avoidance in non-movement areas is that of the pilot.