On August 27, 1999, about 1004 Alaska daylight time, a Gates Lear Jet, model 35 airplane, N90WR, operated by F.S. Air Service, Inc., of Anchorage, Alaska, sustained substantial damage during a hard landing at Gulkana Airport, Gulkana, Alaska. Gulkana is located about 8 miles northeast of Glennallen, Alaska, at 62.09.29 north latitude, 145.27.40 west longitude. The airplane was being operated as an instrument flight rules (IFR) medical transport flight under Title 14, CFR Part 91, when the accident occurred. The two certificated airline transport pilots, and the two flight nurses aboard, were not injured. Visual meteorological conditions prevailed at Gulkana, and an IFR flight plan was filed. The flight originated at the Anchorage International Airport, Anchorage, about 0935. During an interview with the National Transportation Safety Board investigator-in-charge on August 30, the captain of the accident airplane reported that the airplane was being positioned in order to transport a patient to Anchorage. He stated that it had been previously agreed upon that the outbound trip to Gulkana was to be flown by the first officer. The captain said that the first officer made a VOR instrument approach to runway 14. He said that as the flight descended below the cloud cover and the airport environment came into view, it was determined that the airplane was too high, and left of the runway centerline. He said that in an attempt to lose altitude and align the airplane with the centerline, the first officer turned the airplane to the right, retarded the throttles, and applied nose down elevator. The captain said that as the airplane passed over the runway threshold, the airspeed decreased rapidly, and an excessive descent rate was noted. He said that he then took control of the airplane, and applied full engine power in order to cushion the touchdown. The captain characterized the touchdown as "firm", but within acceptable limits. He added that the initial touchdown was made on the left main landing gear, and with the left wing low. After landing, the airplane was taxied to the parking area, and the medical crew and flight crew disembarked uneventfully. The captain and first officer accompanied the medical crew to the hospital. Both crew members stated that a postlanding inspection was not accomplished. Both pilots, the two flight nurses, and one patient, returned to the airport about 45 minutes later, and prepared for the return trip to Anchorage. The first officer said that just prior to departure, she made a quick walk around inspection of the airplane. She stated that she saw no airframe anomalies during her inspection. The flight departed for the return trip to Anchorage about 1125. After arrival in Anchorage, ground personnel discovered a 3 feet by 4 inch scrape located on the lower portion of the left wing-tip fuel tank, and wrinkling of the upper left wing panel, adjacent to the left wing-tip fuel tank attach point. The closest weather observation station is located at the Gulkana Airport. On August 27, at 0950, a contract weather observer was reporting in part: Sky conditions and ceiling, 400 feet scattered, 2,400 feet broken, 5,000 feet overcast; visibility, 20 statute miles; wind, 20 degrees at 5 knots. Both flight crew members noted that there were no preaccident mechanical anomalies with the airplane.