NTSB Factual Report

On March 19, 2016, at 1050 eastern daylight time, a Cessna 210L, N59196, sustained substantial damage when the main landing gear collapsed during a precautionary landing at the Myrtle Beach International Airport (MYR), Myrtle Beach, South Carolina. The private pilot and the two passengers were not injured. The airplane was registered to a private corporation and operated by the pilot as a 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions existed at the airport at the time of the accident and an instrument flight rules flight plan was filed. The flight originated at MYR at 1001 and was destined for Hilton Head Island Airport (HXD), Hilton Head, South Carolina.

The pilot stated that he performed a thorough preflight inspection and engine run-up utilizing the appropriate checklists before he departed and everything was normal. About 10 minutes after takeoff, with the landing gear and flaps fully retracted, the pilot noticed the airplane began to lose electrical power and contacted air traffic control to let them know he wanted to return to MYR. The pilot said he was cleared to return and shortly after he lost all electrical power. The adult passenger then called the control tower via a cell phone and was cleared to land. The landing gear, which is extended and retracted by hydraulic actuators powered by an electrically-driven hydraulic power pack, was disabled due to the electrical failure, so the pilot had to manually pump the gear down via the emergency gear-extension handle. The pilot said he attempted to pump the landing gear down, but the main landing gear would not fully extend. Only the nose wheel extended to what appeared to be the fully down and locked position.

The pilot said it would normally require about 45-47 pumps of the emergency gear extension handle to fully extend the landing gear; however, after about 10 pumps, it felt as if there was no hydraulic pressure in the system and it "didn't seem normal." The pilot tried to pump the gear down for about 20 minutes before realizing he would have to land with unlocked landing gear. The pilot said the landing was smooth and the main landing gear held the support of the airplane for a while before they collapsed and the rear of the airplane bounced on the ground. The airplane skidded to a stop resulting in substantial damage to the left horizontal stabilizer. The belly of the fuselage, main landing gear, and left wing tip were also damaged. According to first responders, the left wing was leaking fuel and there was a small hydraulic leak coming from about 1-foot behind the nose wheel.

A postaccident examination of the engine by a Federal Aviation Administration (FAA) inspector revealed the electrical failure was due to the alternator's primary wire being corroded and broken off of the terminal. A review of the maintenance logbooks revealed the last annual was completed in March 2015, at an engine total time of 1,015.5 hours. There were no entries that the alternator had been repaired in the last 12 months and the pilot reported no mechanical issues prior to the accident flight.

A mechanic, who was on scene shortly after the landing and had recovered the airplane, stated that one of the main landing gear actuators had sustained impact damage and was leaking a small amount of hydraulic fluid. He did not observe any mechanical issues with the landing gear system other than the damaged actuator. The airplane's last annual inspection was completed in March 2015, at an airframe total time of 4,103.2 hours. There was a maintenance entry on November 12, 2015, for the hydraulic system accumulator and right main gear door actuator, which were removed and repaired. The landing gear was tested after the repair and a leak check was performed. The pilot said there were no issues with the landing gear hydraulics after the work was performed. He also stated that he did not test the emergency gear extension system after this repair and had not practiced any manual gear extensions in the airplane in several years.

According to the airplane's pilot operating handbook, page 7-11, LANDING GEAR SYSTEM, "Hydraulic system fluid level may be checked by utilizing the dipstick/filler cap, on the power pack, behind a snap-out cover panel on the right side of the control pedestal. The system should be checked at 25-hour intervals. If the fluid level is at or below the ADD line on the dipstick, hydraulic fluid should be added." According to the FAA inspector, who checked the hydraulic fluid level several days after the accident, noted it was at the ADD level. The pilot stated that he did not check hydraulic fluid level before the accident flight but did check it the day before and the level was "ok."

The pilot held a commercial pilot certificate for airplane single-engine land, instrument airplane. His last FAA third-class medical was issued on March 15, 2016. The pilot reported a total of 1,149 total hours, of which, 327 hours were in the accident airplane.

NTSB Probable Cause

A complete loss of electrical power, which resulted from the separation of an alternator wire due to corrosion. Contributing to the accident was the failure of the emergency landing gear extension system due to a lack of hydraulic fluid, which resulted in insufficient pressure to extend the landing gear.