# NTSB SEA01LA165: Cessna T210L, N6721M, Olympia, WA, September 3, 2001 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: September 2, 2001, 17:00 local (Sep 3, 2001, 00:00 UTC) - Place: Olympia, WA - Coordinates: 47.11098, -122.76081 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=47.1110&lon=-122.7608&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report August 26, 2003 - Report: Approved by Office Director - Parties: Seattle FSDO - NTSB case key (mKey): 53457 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA01LA165 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/53457/pdf - Page: https://openairdocs.org/ntsb/SEA01LA165 ## Probable cause The inability of the landing gear to fully extend due to the failure of a hydraulic hose in the nose gear extension system. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, approach - hydraulic system,line - failure (cause) - Wheels up landing, landing - flare/touchdown - gear extension - not possible, pilot in command (cause) ## Analysis During the gear lowering sequence, the hose fitting on the nose gear actuator gear-down hydraulic hose separated from the body of the hose. Subsequently, the hydraulic fluid in the gear actuating system drained out of the failed hose. The pilot was then unable to move any of the gear from their position at the time of the failure. He was therefore forced to land the aircraft with the nose gear in the full-down position, but with both main gear only partially extended. Upon touchdown, both main gear folded back into the wheel well, and the empennage contacted the runway. ## Factual narrative On September 2, 2001, approximately 1700 Pacific daylight time, a Cessna T210L, N6721M, landed with the main landing gear only partially extended at Olympia Airport, Olympia, Washington. The pilot, who was the sole occupant, was not injured, but the aircraft, which is owned and operated by the pilot, sustained substantial damage. The 14 CFR Part 91 personal pleasure flight, which departed Empire, Nevada about four hours prior to the accident, was being operated in visual meteorological conditions. No flight plan had been filed. There was no report of an ELT activation. According to the pilot, when he moved the gear handle to the down position, the nose gear lowered and locked in place, but both main gear legs failed to fully extend. The pilot then checked the hydraulic reservoir and found it empty. He therefore filled the reservoir with water and tried again to lower the gear, but was unsuccessful. He then attempted to maneuver the aircraft in a manner that would cause the main gear legs to fully extend by gravity, but they did not do so. Since the gear could not be moved up or down, the pilot was forced to land with the nose gear fully extended and both main gear partially retracted. During the landing, both main gear folded back into the wheel wells, allowing the empennage to impact the runway surface. A post-accident inspection revealed that the nose gear extension actuator gear-down hydraulic hose had failed, and the hydraulic fluid had drained from the system through this failure. The failure consisted of the hose fitting (with a portion of the hose outer skin still attached to it) separating from the body of the hose. The hose was able to be positively identified as an original equipment Cessna part (#S2178-3-0144 ). According to Cessna's Special Inspection Items list for this aircraft, this hose should be inspected and replaced as required each 1000 hours or five years. The location of the failure of the hose's outer skin was approximately 3/32 of an inch inside the fitting collar, and would not normally be in view during an on-aircraft visual hose inspection. A review of the aircraft log books revealed that the last time a nose wheel hydraulic actuator hose had been replaced was 25 years prior to the accident. ## Aircraft - Registration: [N6721M](https://openairdocs.org/deregistered/N6721M-2013-10-31), registration cancelled 2013-10-31, S/N 21061137, built 1975 (OpenAirDocs) - Reported make and model: Cessna T210L - Registry model: [Cessna T210L](https://openairdocs.org/model/cessna-t210l) (registry code 2073449) (OpenAirDocs) - Registry engine: [Continental TSIO-520 series](https://openairdocs.org/engine/continental-tsio-520-series) (registry code 17040, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 21061137 - Airframe hours: 3035 - Engines: Continental TSIO-520-J 310 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Michael H. O'Rear - Airworthiness certificate: Standard, Normal - Last inspection: Annual, April 16, 2001, 70 hours before - Departed: IAB, Empire, NV - Destination: OLM, Olympia, WA - Airport: OLM, Olympia Airport, runway 26, 4,100 × 150 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 51; injuries: none; private; airplane ratings: single-engine land; instrument ratings: airplane; medical: class 3, valid medical--no waivers/lim.; last flight review October 11, 1999; seat: left; flight hours: 1,333 total, 228 in this make and model, 1,213 as pilot in command, 54 in the last 90 days, 15 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 230° at 8 knots - Visibility: 100 statute miles - Lowest ceiling: none - Temperature: 75 °F ## 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 20010902023959A](https://openairdocs.org/incident/20010902023959A), Sep 2, 2001: Cessna T210L, Olympia, WA, No damage. (-23) During landing, nose gear extended and locked, but main gear did not lock into place. Pilot tried to lock main gear using the hand hydraulic pump with no… 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.