HISTORY OF FLIGHT On April 5, 2002, approximately 1910 mountain standard time, a Cessna 182E, N3184Y, registered to an individual and being flown by a private pilot sustained substantial damage during the landing roll on runway 16 at the Red Lodge airport, Red Lodge, Montana. The pilot was uninjured. Visual meteorological conditions existed and no flight plan had been filed. The flight, which was personal, was operated under 14CFR91, and originated from Hailey, Idaho, about 1710. The pilot reported that upon executing a 20-degree flap landing on the 4,000-foot long, asphalt runway, he held the nose wheel off the deck until the airplane had slowed. As he allowed the nose wheel to touch the runway about midfield, the aircraft veered sharply to the left and the pilot was unable to prevent the aircraft from departing the left side of the runway. He reported that his airspeed was about 20 knots when the nose wheel touched down and he experienced the loss of control. PERSONNEL INFORMATION The airplane single-engine land rated private pilot reported a total of approximately 151 hours of flight experience of which about two-thirds were in the Cessna 182. He also reported a total of 45 hours of pilot-in-command time, all in the Cessna 182. AIRCRAFT INFORMATION N3184Y, a Cessna 182E "Skylane" was manufactured in 1962 and had an approximate total of 6,089 hours on the airframe at the time of the accident. The following is a chronology of significant nose wheel maintenance (other than lubrication and tire replacement) from the aircraft's manufacture: DATE: ACTION: 08/11/65 Installed new shimmy damper 02/02/69 Rebuilt nose gear 06/29/72 Rebuilt nose gear strut 12/04/75 Installed new shimmy damper 12/13/76 Rebuilt nose gear strut 05/25/80 Remove/replace shimmy nose steering collar & support ring 10/16/97 Installed new bolts in nose gear scissors + nose wheel races & bearings Additionally, the airframe logbook indicated that on August 27, 1998, the aircraft's Continental O-470 engine was removed and a Continental IO-520-F48B was installed in its place. Additionally, the original two-blade propeller was removed and replaced with a three-blade propeller and the engine mounts were changed, all three changes per Supplemental Type Certificates. The basic weight of the IO-520 engine is approximately 51 pounds less than the weight of the O-470 engine. METEOROLOGICAL INFORMATION The pilot reported that the winds were calm during his landing at Red Lodge. The aviation surface weather observation for Cody, Wyoming, 41 nautical miles east-southeast reported winds from 240 degrees magnetic at 4 knots. WRECKAGE AND IMPACT INFORMATION The aircraft departed runway 16 and came to rest a short distance east of the eastern edge of the runway pavement in grass and light snow. The approximate location of the aircraft's final resting place was 45 degrees 11.25 minutes north latitude and 109 degrees 16.04 minutes west longitude. The aircraft crossed a shallow ditch approximately 2-3 feet deep running parallel to the east side of the runway. The pilot reported that as the aircraft's left wheel entered the ditch the aircraft's left wing impacted the ground (refer to photograph 1). The aircraft came to rest on both main wheels and the nose wheel strut with its longitudinal axis oriented approximately 45 degrees to the runway (refer to photograph 2). The pilot found the nose wheel with the separated portion of nose wheel fork approximately 150 yards beyond the aircraft. TESTS AND RESEARCH The separated portion of the nose gear fork (that portion which remained attached to the nose wheel) was shipped to the Safety Board's Materials Laboratory where the component was subjected to metallurgical examination. The examination revealed that the fork fractured transversely in the attachment area of the shock strut assembly. Visual examination of the fracture revealed thumbnail features typical of fatigue cracking that emanated from five different fracture planes at the upper outer surface. The fatigue regions were very smooth, contained crack arrest positions, and were darkly discolored. The maximum depth of the fatigue cracks was 0.2 inch. One of the fatigue cracks intersected the forge parting plane. The exterior surface of the fork showed no evidence of corrosion pitting or mechanical damage adjacent to the fatigue regions. Fracture surfaces outside the fatigue regions showed ductile dimple features typical of overstress separation (refer to Metlab Report 02-53). ADDITIONAL INFORMATION On-site examination of the wreckage was conducted on April 8, 2002, and the nose wheel and attached fork sections were retained for further examination at that time. The retained components were returned to Mr. Bruce Allen via Federal Express on June 24, 2002 (refer to attachment FE-I).