Incident Details
On April 19, 2012, at 1715 eastern daylight time, a Cessna 210, registration N96050, experienced a main landing gear collapse during the landing roll at Gatlinburg Pigeon Forge Airport (GKT) in Gatlinburg, Tennessee. The airplane, operating under Title 14 Code of Federal Regulations Part 91 as a personal flight, sustained substantial damage to the left horizontal stabilizer. The certificated private pilot was not injured. Visual meteorological conditions prevailed, and an instrument flight rules (IFR) flight plan had been filed. The flight originated from Kennett, Missouri, at 1526.
Pilot Actions
Upon arrival near GKT, the pilot canceled his IFR flight plan and entered a right traffic pattern for landing. After completing the checklist and lowering the landing gear, he observed that the hydraulic unit remained on and the cockpit did not indicate a green landing gear light. Looking outside, he saw the nose wheel extended but both main landing gear only partially extended. Recycling the landing gear handle yielded negative results, as did several attempts of the emergency landing gear extension procedure. The pilot then contacted a mechanic via airplane radio. After a flyby, it was decided to check the hydraulic fluid level. The pilot climbed to 3,500 feet above ground level, engaged the autopilot, retrieved tools and oil from the rear of the airplane, and added oil to the hydraulic fill port. Further attempts to recycle the landing gear were unsuccessful. With about 5 gallons of fuel remaining, the pilot attempted negative-G maneuvers, also without success. He then executed a straight-in approach with the nose wheel down and the main landing gear partially extended. During touchdown, the airplane veered left off the runway and came to rest upright in a grassy area.
Examination Findings
Post-incident examination of the landing gear system revealed that the landing gear down pressure hose (part number S2178-3-0144) on the nose landing gear was ruptured. This condition prevented the main landing gear from fully extending and locking in the down position when the landing gear was deployed via the handle or emergency extension.
Maintenance Records
Review of the Cessna Aircraft Company Series Service Manual (D20004-5-13, Revision 5, July 1, 2004) specifies a special inspection item (19) requiring inspection and replacement of all rubber hydraulic hoses in the retraction and brake system every 1,000 hours or 5 years. The airframe and power plant mechanic with inspection authority who had performed inspections on the airplane for the previous three years stated to the NTSB investigator that the hoses were flexible, showed no fraying, and held pressure without leaks during those inspections. However, no logbook entry indicated that the hydraulic hoses had been replaced within the last 5 years or 1,000 hours.