Event
On March 19, 2016, at 1050 eastern daylight time, a Cessna 210L, registration N59196, experienced a collapse of the main landing gear during a precautionary landing at Myrtle Beach International Airport (MYR), Myrtle Beach, South Carolina. The airplane sustained substantial damage. The private pilot and the two passengers were not injured. The flight, operated under 14 Code of Federal Regulations Part 91 as a personal flight, had originated at MYR at 1001 and was destined for Hilton Head Island Airport (HXD), Hilton Head, South Carolina. Visual meteorological conditions prevailed, and an instrument flight rules flight plan was filed.
According to the pilot, he performed a thorough preflight inspection and engine run-up using the appropriate checklists before departure, and everything was normal. About 10 minutes after takeoff, with the landing gear and flaps retracted, the pilot noticed a loss of electrical power and contacted air traffic control to return to MYR. Shortly after being cleared to return, the airplane lost all electrical power. An adult passenger then contacted the control tower via cell phone and received clearance to land. The landing gear, extended and retracted hydraulically by an electrically-driven power pack, was disabled due to the electrical failure. The pilot attempted to extend the gear manually using the emergency gear-extension handle but found that the main landing gear would not fully extend. Only the nose wheel appeared to lock down. The pilot reported that normally about 45-47 pumps of the handle are needed, but after about 10 pumps, hydraulic pressure seemed absent. He pumped for about 20 minutes before deciding to land with the gear unlocked. The landing was smooth; the main landing gear initially held the airplane's weight but then collapsed, causing the rear of the airplane to bounce. The airplane skidded to a stop, resulting in substantial damage to the left horizontal stabilizer, the belly of the fuselage, the main landing gear, and the left wing tip. First responders noted a fuel leak from the left wing and a small hydraulic leak about 1 foot behind the nose wheel.
Post-Accident Examination
A Federal Aviation Administration (FAA) inspector examined the engine and found that the electrical failure was due to the alternator's primary wire being corroded and broken off the terminal. The pilot reported no mechanical issues before the accident flight.
A mechanic who recovered the airplane observed that one main landing gear actuator had sustained impact damage and was leaking a small amount of hydraulic fluid. No other mechanical issues with the landing gear system were noted beyond the damaged actuator.
Maintenance History
Review of maintenance logbooks showed that the last annual inspection was completed in March 2015, at an engine total time of 1,015.5 hours and an airframe total time of 4,103.2 hours. No entries indicated repair of the alternator in the preceding 12 months. A maintenance entry on November 12, 2015, documented removal and repair of the hydraulic system accumulator and right main gear door actuator; the landing gear was tested and a leak check performed afterward. The pilot stated he did not test the emergency gear extension system after that repair and had not practiced manual gear extensions in the airplane for several years.
According to the airplane's pilot operating handbook, the hydraulic system fluid level should be checked at 25-hour intervals using a dipstick/filler cap on the power pack. The FAA inspector checked the fluid level several days after the accident and found it at the ADD line. The pilot stated he had checked the fluid level the day before the accident and it was "ok."
Pilot Information
The pilot held a commercial pilot certificate with airplane single-engine land and instrument ratings. His most recent FAA third-class medical was issued on March 15, 2016. He reported a total of 1,149 flight hours, including 327 hours in the accident airplane.