History of Flight
On September 20, 2017, at 1314 Pacific daylight time, a Cessna 210F airplane, registration N7330E, sustained substantial damage to the left horizontal stabilizer after the main landing gear collapsed during the landing roll at Sacramento Executive Airport, Sacramento, California. The private pilot and passenger, who held a flight instructor certificate, were not injured. The airplane had been recently purchased by the private pilot and was registered to the previous owner at the time of the accident. The flight was conducted under Title 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan was filed.
Both occupants provided differing accounts of their operational roles. The pilot, seated in the left seat, reported that it was his first flight in the airplane and that he understood it would be a training flight. The instructor stated that he had no previous experience in the Cessna 210 series and had explicitly told the pilot and his mechanic that he would not operate the controls or provide instruction, but would act only as an observer.
The pilot stated that his intention was to perform a traffic pattern flight followed by a touch-and-go landing. He reported that the flight was uneventful, that he flew the takeoff and landing approach, and that the instructor operated the landing gear handle and assisted with flight controls during the landing roll. He stated that prior to landing, he visually confirmed the gear extension via the gear mirrors. Shortly after landing, the airplane began to shake, and after traveling about 100 feet, it veered left. He applied right rudder and felt the instructor doing the same. The airplane then dropped onto its belly.
The instructor provided an extensive statement, reporting that the mechanic who arranged the flight requested vigilance regarding the landing gear being down and locked. The instructor reiterated that he did not manipulate any controls until the airplane began to veer off the runway and that he never operated the landing gear handle. He stated that after the pilot extended the gear, he observed the green indicator light and confirmed extension via the gear mirrors.
Landing Gear System
The landing gear and flaps are extended and retracted by hydraulic actuators powered by an engine-driven pump and accumulator. The nose gear retracts forward and up; its doors remain open when extended. The main gear rotates aft and up into wells; doors remain closed except during transition. All gears have positive mechanical up and down locks operated by separate actuators. Limit switches control two position indicator lights: red for up, green for down and locked. The switches are in series, so all three gears must lock before either light illuminates. During extension, the nose gear locks before the main gear.
The gear is controlled by a four-position handle: Up-Operating, Up-Neutral, Down-Neutral, and Down-Operating. The handle is pulled out and moved to the desired operating position, then released. A detent holds it in the operating position until the cycle completes, after which it returns to neutral. A safety switch actuated by the nose gear strut restricts the handle to prevent inadvertent retraction when the nose strut is compressed.
The instructor could not recall whether the gear handle was in Down-Neutral or Down-Operating, but stated that the mechanic, who arrived first, entered the cabin, turned on the master switch, and moved the gear handle. The mechanic reported that when he arrived, the handle was in Down-Operating; later, after lifting the airplane with a hoist, he turned on the master switch. Immediately, the gear completed its cycle, the handle moved to Down-Neutral, and the green light illuminated.
Post-Accident Examination
Photographs taken after the accident showed the nose gear extended, both main gear partially retracted with their doors open, and flaps fully extended. Three black skid marks were observed on the runway, swerving from the centerline to the airplane's final position left of the runway edge. The outer width of the skid marks was about 34 inches.
The airplane was removed and stored at the mechanic's shop, where it was mounted on jack stands and examined by an FAA inspector the following week. No mechanical anomalies were observed in the landing gear system beyond damage to the gear doors. The gear was successfully extended and retracted multiple times using the gear handle, and both red and green position lights illuminated appropriately.