# NTSB LAX97LA101: Cessna 210H, N6137F, Big Bear City, CA, February 8, 1997 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: February 8, 1997, 09:55 local (17:55 UTC) - Place: Big Bear City, CA - Coordinates: 34.259723, -116.840812 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=34.2597&lon=-116.8408&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report May 30, 1997 - Report: Approved by Office Director - NTSB case key (mKey): 29725 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX97LA101 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/29725/pdf - Page: https://openairdocs.org/ntsb/LAX97LA101 ## Probable cause a corroded landing gear down limit switch, which resulted in a retracted left main gear during the landing sequence. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, landing - landing gear,gear switch - corroded (cause) - landing gear,gear indicating system - malfunction - landing gear,gear locking mechanism - not engaged - Wheels up landing, landing - landing gear,main gear - malfunction ## Analysis The pilot had normal gear indications while landing. The airplane settled on its left side after the left main landing gear retracted into the wheel well during landing roll. The landing gear down limit switches were found stuck and appeared corroded and dirty. The stuck switches illuminated the landing gear down light, inconsistent with the landing gear position. They affected the sequence in which the landing gear operated, in that once the nose was down, the sequencing valve would transfer hydraulic pressure from the main gear actuators to the landing gear door actuators before the main landing gear would fully extend to the locked position. The airplane had been tied down outside on the airport ramp and had only flown 10 hours since the annual inspection, which was completed on 2/16/96. ## Factual narrative On February 08, 1997, at 0955 hours Pacific standard time, a Cessna 210H, N6137F, lost control after landing with the left main landing gear retracted on runway 26 at the Big Bear City Airport, Big Bear City, California. The airplane sustained substantial damage and the certificated private was not injured. The airplane was being operated as a personal flight by the pilot/owner. The flight originated in El Monte, California, about 0900. Visual meteorological conditions prevailed at the time. The pilot indicated he remained in the traffic pattern after takeoff from the El Monte Airport. After completing three touch-and-go landings he departed the traffic pattern. He flew west over the City of Los Angeles and then turned eastbound to Big Bear City. The pilot indicated he had normal gear indications while landing. During the landing roll, the airplane settled on its left side. The left wing tip, left wing flap and aileron, left horizontal stabilizer, and the left elevator were damaged as the airplane slid off the runway. The airplane was examined by an airframe and powerplant (A&P) mechanic. The left main landing gear was found retracted in the wheel well with the gear door closed. Further examination revealed the down limit switches were stuck and would illuminate the single landing gear down light inconsistent with the landing gear position. The A&P stated the switches appeared corroded and dirty. The A&P also stated the stuck switches would affect the sequence in which the landing gear operated; in that, once the nose was down the sequencing valve would transfer hydraulic pressure from the main gear actuators to the landing gear door actuators before the main gear was fully down in the locked position. The pilot/owner indicated the airplane was tied down outside on the El Monte Airport ramp and had only flown 10 hours since the annual inspection on February 16, 1996. ## Aircraft - Registration: [N6137F](https://openairdocs.org/aircraft/N6137F), registered now, S/N 21059037, built 1968 (OpenAirDocs) - Reported make and model: Cessna 210H - Registry model: [Cessna 210H](https://openairdocs.org/model/cessna-210h) (registry code 2073436) (OpenAirDocs) - Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 59037 - Airframe hours: 1197 - Engines: Continental IO-520-A 285 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Chow, T.G - Registered owner: Wingland, Inc. - Airworthiness certificate: Standard, Normal - Last inspection: Annual, February 16, 1996, 10 hours before - Departed: EMT, EL MONTE, CA - Destination: L35 - Airport: L35, Big Bear City, runway 26, 5,850 × 75 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 69; private; airplane ratings: single-engine land; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 1,069 total, 740 in this make and model, 1,069 as pilot in command, 1 in the last 90 days, 1 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Lowest ceiling: 2,500 ft broken - Temperature: 41 °F, dew point 12 °F - Altimeter: 30.00 inHg - Observed at: L35 ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19970208001399A](https://openairdocs.org/incident/19970208001399A), Feb 8, 1997: Cessna 210H, Big Bear, CA, Substantial damage. Left main landing gear folded on landing roll. Gear not locked down due stuck limit switch blocked sequencing. From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.