On July 30, 2019, at 1600 eastern daylight time, a Cessna 210E, N2362F, owned and operated by a private individual, sustained substantial damage while landing at Lovell Field Airport (CHA), Chattanooga, Tennessee. The private pilot and two passengers were not injured. The personal flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan was filed for the flight that originated from Destin Executive Airport (DTS), Destin, Florida, about 1120 central daylight time, and was destined for Mark Anton Airport (2A0), Dayton, Tennessee. According to the pilot, he performed a preflight inspection and did not note any anomalies with the airplane, nor did he notice any hydraulic leaks near the landing gear system. After takeoff from DTS, the landing gear would not lock into place on the first attempt to retract. The pilot cycled the landing gear with the same result. He placed the landing gear handle in the neutral position and continued the flight. The pilot reported that the enroute portion of the flight was uneventful. Upon arrival at 2A0, the pilot selected the landing gear handle in the "DOWN" position. The gear down-and-locked light did not illuminate, and visual inspection revealed that the landing gear was hanging under the airplane and was not locked. The pilot performed the landing gear malfunction procedures in the pilot operating handbook to no avail. He utilized the manual landing gear extension procedure; however, the landing gear would still not lock, and he observed hydraulic fluid on the floorboards near the passenger seat. Aerial observation of the landing gear by airport personnel indicated that the nose gear was extended, and the main gear was trailing and not fully extended. The pilot declared an emergency and diverted to CHA and landed on runway 20 with the nose gear down and locked and the two main landing gear partially extended. As the airplane decelerated it veered to the right, impacted a taxiway sign, and slid to a stop in the grass. Examination of the accident scene by a Federal Aviation Administration (FAA) inspector revealed that the airplane came to rest upright on the right side of the runway resting on the right wingtip, fuselage, and nose wheel. Both main landing gear were collapsed. The right rear empennage was torn, and the right and left horizontal stabilizers were substantially damaged. The pilot held a private pilot certificate with a rating for airplane single-engine land. His most recent FAA first-class medical certificate was issued on June 7, 2017. According to pilot logbooks, the pilot had accrued 123.8 total flight hours at the time of the accident, of which 83.9 hours were in the same make and model as the accident airplane. The 1553 weather conditions at CHA included wind 150° at 8 knots, visibility 10 statute miles, light rain, few clouds at 2,000 ft, scattered clouds at 4,000 ft, broken cloud layers at 10,000 ft and 25,000 ft, temperature 23° C, dew point 18° C, and an altimeter setting of 30.05 inches of mercury. According to FAA records, the 4-seat, high-wing, retractable gear airplane, serial number 21058562, was manufactured in 1965. According to airplane maintenance records, the most recent annual inspection was completed on October 10, 2018, at a recorded airframe total time of 4,950.3 hours. The airplane was powered by a Continental IO-520-A, 285-hp engine. Engine maintenance records showed that at the time of the most recent annual inspection, the engine had accrued 2,996 total hours and 932.4 hours since overhaul. At the time of the accident, the engine had accrued 3,057 hours. Examination of the landing gear system by a mechanic and an FAA inspector at a maintenance facility revealed a low level of hydraulic fluid in the reservoir and evidence of hydraulic fluid seepage near both landing gear actuators and the emergency gear-extension handle. The left actuator was broken, and operation of the emergency gear handle did not feel "normal." A placard on the firewall stated, "Check fluid level every 25 hours;" however, the pilot stated that it had not been checked since the last annual inspection. According to the pilot, he purchased the airplane in 2017 after it had been sold at auction without its logbooks. The landing gear saddle was the subject of an Airworthiness Directive (AD), AD 76-14-07 R2. The AD required replacement of the landing gear saddle, and after 1,200 hours of service on the new part, annual dye penetration inspections. There were no records in the logbook to indicate that the AD had been complied with or that an annual inspection of the part had ever been performed. According to cockpit placards and the manufacturer's service manual, the hydraulic reservoir was to be inspected and replenished every 25 hours, the landing gear hydraulic system was to be checked for leaks and external damage to components or mounting structure every 100 hours, and all rubber parts in the landing gear system were to be replaced every 5 years. In addition, an overhaul of the landing gear system selector valve, emergency hand pump, and pressure switch was to take place every 5 years. Available maintenance records did not reveal that these recommended inspections and overhauls had been performed.