On June 17, 1998, about 1730 Alaska daylight time, a wheel equipped Cessna 207 airplane, N2162C, sustained substantial damage as a result of a bird strike during approach to the Bethel Airport, Bethel, Alaska. The airplane was being operated as a visual flight rules (VFR) on-demand passenger flight under Title 14, CFR Part 135, when the accident occurred. The airplane is registered to and operated by Kusko Aviation, Inc., Bethel, Alaska. The certificated commercial pilot, and the three passengers aboard, were not injured. Visual meteorological conditions prevailed, and VFR company flight following procedures were in effect. The flight originated at the Quinhagak Airport, Quinhagak, Alaska, about 1655. During a telephone conversation with the National Transportation Safety Board investigator-in-charge, on July 20, 1998, the pilot stated that while on a left downwind for landing on runway 18, he noticed a brown object pass in front of the windshield, from left to right, striking the right wing. The pilot said he was able to continue the approach, and made a normal landing. Company maintenance personnel performed a postflight inspection and reported substantial damage to the right wing's leading edge and rib assemblies. They noted what appeared to be goose feathers imbedded in the damaged portion of the wing. In the pilot/operator report (NTSB form 6120.1/2) submitted by the pilot, and dated August 7, 1998, he reported that right wing leading edge skin was crushed back to the forward portion of the spar. The entire leading edge was replaced between the tip cap, and outboard of the attach point of the wing strut. The pilot noted that there were no preaccident mechanical anomalies with the airplane.