On June 26, 2005, at 1010 mountain daylight time, a Beech 1900D, N240GL, owned and operated by Great Lakes Aviation, LTD., sustained minor damage when it struck an airport security fence while taxiing at the Walker Field Airport, Grand Junction, Colorado. The captain, first officer, and 17 passengers on board were not injured. Visual meteorological conditions prevailed, and an instrument flight rules flight plan was filed for the Title 14 Code of Federal Regulations Part 121 scheduled domestic passenger flight. The flight was originating at the time of the incident and was destined for Denver, Colorado. According to the captain, the number 2 engine (right) was operating and he had given the ground marshals clearance to remove the wheel chocks. The first officer closed the cabin door and had completed the passenger safety briefing. After the first officer had completed the briefing, the captain turned in his seat to demonstrate to the first officer how to secure a component of the cabin door from "rattling" in-flight. During the captain's demonstration, the first officer was standing in the forward cabin. While the flight crew's attention was diverted, the airplane taxied forward, rolled onto a curb, and struck an airport security fence. Examination of the aircraft by airport personnel revealed the right propeller blades were separated near the hub, the right engine cowling and the radome were punctured.