# NTSB DEN00LA020: Cessna 210D, N3928Y, Sheridan, WY, November 21, 1999 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: November 20, 1999, 21:00 local (Nov 21, 1999, 04:00 UTC) - Place: Sheridan, WY - Coordinates: 44.789894, -106.949859 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.7899&lon=-106.9499&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report November 30, 2000 - Report: Approved by Office Director - NTSB case key (mKey): 47813 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=DEN00LA020 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/47813/pdf - Page: https://openairdocs.org/ntsb/DEN00LA020 ## Probable cause The partial failure of the engine driven hydraulic pump. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, landing - roll - hydraulic system,pump - failure,partial (cause) - landing gear,gear locking mechanism - unlocked - Main gear collapsed, landing - roll ## Analysis The pilot said that this was the first flight after the annual inspection. When he put the leading gear handle down for landing, he didn't get a positive gear lock light, so he cycled the leading gear several times in an attempt to get a positive gear down and locked indication. He attempted to hand pump the gear down, but still had no positive down and locked light. He landed the airplane, and during the landing roll the right main landing gear failed. Postaccident examination of the engine driven hydraulic pump pressure revealed that its output was 200 pounds per square inch (psi). The maintenance personnel that worked on the airplane said that normal pump pressure output was 2,725 psi. The hydraulic pump was replaced, and the landing gear cycled normally. ## Factual narrative On November 20, 1999, at 2100 mountain standard time, a Cessna 210D, N3928Y, was substantially damaged during landing at Sheridan County Airport, Sheridan, Wyoming. The private pilot, the sole occupant in the airplane, was not injured. The airplane was being operated by the pilot under Title 14 CFR Part 91. Visual meteorological conditions prevailed for the local flight which originated approximately 35 minutes before the accident. No flight plan had been filed. The pilot said that this was the first flight after the annual inspection. He was flying from Billings, Montana, to Sheridan, Wyoming, and had put the leading gear handle down for landing. He didn't get a positive gear lock light, so he cycled the landing gear several times in an attempt to get a positive gear down and locked indication. He then attempted to hand pump the gear down, but still had no positive down and locked light. He landed the airplane, and during the landing roll the right main landing gear collapsed. Subsequently, the right horizontal stabilizer and the right wing tip were bent when they struck the ground. Postaccident examination of the engine driven hydraulic pump pressure revealed that its output was 200 pounds per square inch (psi). The maintenance personnel that worked on the airplane said that normal pump pressure output should be 2,725 psi. The hydraulic pump was replaced, and the landing gear cycled normally. ## Aircraft - Registration: [N3928Y](https://openairdocs.org/deregistered/N3928Y-2018-01-04), registration cancelled 2018-01-04, S/N 21058428, built 1964 (OpenAirDocs) - Reported make and model: Cessna 210D - Registry model: [Cessna 210D](https://openairdocs.org/model/cessna-210d) (registry code 2073414) (OpenAirDocs) - Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 21058428 - Airframe hours: 3725 - Engines: Continental I0-520 285 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: John W. Krenek - Airworthiness certificate: Standard, Normal - Last inspection: Annual, November 20, 1999, 1 hours before - Departed: BIL, BILLINGS, MT - Destination: SHR - Airport: SHR, Sheridan County Airport, runway 14, 8,300 × 100 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 52; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 172 total, 22 in this make and model, 110 as pilot in command, 24 in the last 90 days, 15 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Night/bright - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 34 °F, dew point 30 °F - Altimeter: 29.00 inHg - Observed at: SHR ## Other investigations on N3928Y (1) 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. - [NTSB FTW68F0399](https://openairdocs.org/ntsb/FTW68F0399), Dec 18, 1967: Cessna 210C (N3928Y), Gatesville, TX, substantial damage 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.