WPR10LA140

The pilot reported that, after departing for a local flight, he attempted to retract the landing gear but the landing gear did not retract. He verified the position by looking out of the window and noted that the landing gear appeared to be in the down-and-locked position. The green landing gear position light was not illuminated. Because he thought that the landing gear was in the down-and-locked position, the pilot decided not to use the manual gear extension procedure. During the landing, the right main landing gear collapsed. Postaccident examination and testing of the landing gear system showed that it operated normally and no mechanical anomalies were identified. The underlying cause of the intermittent operation of the landing gear system was not determined. Testing of the manual gear extension system showed that it functioned normally. Had the pilot used the system, he would have received a gear down-and-locked indication and landed normally.

HISTORY OF FLIGHT On February 18, 2010, at 0930 Pacific standard time, a Cessna 210L, N777FW, landed at Aurora State Airport, Aurora, Oregon, and the right main landing gear collapsed. The commercial pilot was operating the airplane under the provisions of 14 Code of Federal Regulations Part 91. The pilot and five passengers were not injured; the airplane sustained substantial damage. Visual meteorological conditions prevailed and no flight plan was filed. The pilot had departed Aurora at 0925. The pilot reported that he arrived at the airport prior to his passengers because his airplane had not been flown for 35 days. After conducting a pre-flight inspection, he started the engine and taxied for fuel. At this time, the landing gear position light appeared to be working normally. After his passengers boarded, he started the engine. Due to the noise from his passengers, he could not recall any audible noise from the landing gear pump. After takeoff, the pilot raised the landing gear selector. He immediately noticed that the performance of the airplane had not changed. He looked at the landing gear position light and it was not illuminated. The pilot then looked out of his window and saw the left main landing gear in the down position. He cycled the landing gear selector several times but there was no response. The pilot then decided that he would return to the airport. The pilot indicated that although he did not have a green light indicating that the landing gear were down-and-locked, he assumed that they were in the down-and-locked position because he could see that they were down. He did not attempt to manually extend the landing gear. During the landing, the right main landing gear collapsed, and the right elevator and stabilizer were bent. AIRCRAFT INFORMATION The airplane, serial number 21060167, was manufactured in 1974. The last annual inspection was completed on April 8, 2009, at a total airframe time of 13,762 hours. According to the maintenance manual for the airplane, the landing gear is hydraulically-operated and retractable. Additionally, it stated that the hydraulic power system included equipment required to provide a flow of pressurized hydraulic fluid to the landing gear system. Main components of the hydraulic system include a self-contained hydro-electric pack, hand pump, gear select switch, and circuit breaker. TESTS AND RESEARCH A Federal Aviation Administration inspector examined the landing gear system on the airplane. With the airplane on the ground and its weight on the landing gear, as electrical power was applied, the green annunciator light illuminated. The amber gear up light did not illuminate. The amber gear up light did illuminate when the press to test was activated. The airplane was then placed on jacks and an operational test of the landing gear and emergency extension systems was conducted. The operation of the hydraulic pump and landing gear extension and retraction systems was normal through tenretraction/extension tests. The operation of the manual gear extension/emergency system was normal. All three gear extended into the down-and-locked position each time. Additional tests were performed with the landing gear position indicating system. With one gear unlocked, neither light illuminated. When no light is illuminated, it is an indication that the gear is transitioning between down-and-locked and up-and-locked. The pilot reported to the inspector that he thought he should have seen a yellow light with the gear unlocked, indicating that the gear was in transit.