Accident Details
On April 30, 2008, about 0945 Alaska daylight time, a Cessna Citation 560XL airplane, registration N590AK, sustained substantial damage while landing at Port Heiden Airport, Port Heiden, Alaska. The airplane, operated by AT&T Alascom, Anchorage, Alaska, was conducting an instrument flight rules (IFR) corporate flight under Title 14, CFR Part 91. Of the six people aboard, the two airline transport certificated pilots and the four passengers were not injured. The flight originated from Ted Stevens Anchorage International Airport, Anchorage, Alaska, about 0820, and an instrument flight plan had been filed.
Flight Information
During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge, the captain reported the purpose of the flight was to transport a crew of telecommunications technicians to Port Heiden. He stated that the approach to runway 23 required a correction for a right crosswind, and the initial touchdown on the 5,000-foot long by 100-foot wide gravel runway was uneventful. As he lowered the nose and applied small left rudder pedal input to correct for the crosswind, the nose wheel touched down. Immediately after, the airplane veered sharply to the left and departed the left side of the runway. The left main landing gear collapsed, and the left wing struck the runway, resulting in substantial damage to the left wing and fuselage. The captain reported no preaccident mechanical anomalies.
Weather Conditions
At 0936, the automated weather observing system (AWOS) at Port Heiden reported: wind 320 degrees at 12 knots; visibility 10 statute miles; clouds and sky condition 600 feet few; temperature 30 degrees F; dew point 28 degrees F; altimeter 29.94 inHg.
Post-Accident Investigation
The Cockpit Voice Recorder (CVR) was removed and sent to the NTSB vehicle recorder laboratory. A Safety Board aerospace engineer reviewed the recorded data and determined that the audio did not offer additional information beyond that obtained from the flightcrew. No CVR listening group was convened, and no transcript was prepared. A summary of key events was included in the public docket. The CVR was released to the owner on November 18, 2008. No parts or components were retained by the Safety Board.
Pilot's Recommendations
The accident airplane was equipped with a nose wheel-mounted gravel kit. In his written report, the captain suggested the accident might have been prevented if the Citation XL had a nose wheel disconnect option similar to that on a Citation V. He noted that without a disconnect, slight rudder/aileron deflection moves the nose wheel slightly, as happens during crosswind landings, and even small nose wheel deflection is magnified on gravel, causing uncommanded sharp turning forces.