# NTSB WPR23LA076: Cessna 210N, N210CU, Morgan, UT, December 26, 2022 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: December 26, 2022, 16:45 local (23:45 UTC) - Place: Morgan, UT · airport environment - Coordinates: 41.148676, -111.76714 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=41.1487&lon=-111.7671&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 106498 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR23LA076 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/106498/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=106498 - Page: https://openairdocs.org/ntsb/WPR23LA076 ## Probable cause Failure of the brake system O-rings on the left landing gear trunnion, which allowed the hydraulic fluid to drain from the left brake system, resulting in a runway excursion and impact with a fence. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: landing gear brakes system](https://openairdocs.org/ntsb-findings/01023240): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [Cessna 210N, 1 case](https://openairdocs.org/ntsb-findings/01023240/cases.md?model=2073453), [All aircraft, 92 cases](https://openairdocs.org/ntsb-findings/01023240/cases.md) - [Landing gear system: brake](https://openairdocs.org/ntsb-findings/01023242): Aircraft › Aircraft systems · Inoperative (probable cause); cases with it: [Cessna 210N, 1 case](https://openairdocs.org/ntsb-findings/01023242/cases.md?model=2073453), [All aircraft, 297 cases](https://openairdocs.org/ntsb-findings/01023242/cases.md) - [Fluids: hydraulic fluid](https://openairdocs.org/ntsb-findings/01071015): Aircraft › Fluids/misc hardware · Fluid level (probable cause); cases with it: [Cessna 210N, 1 case](https://openairdocs.org/ntsb-findings/01071015/cases.md?model=2073453), [All aircraft, 33 cases](https://openairdocs.org/ntsb-findings/01071015/cases.md) - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Attain/maintain not possible (probable cause); cases with it: [Cessna 210N, 1 case](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=2073453), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing-landing roll: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) (defining event); cases with it: [Cessna 210N, 1 case](https://openairdocs.org/ntsb-events/330/sequence.md?model=2073453), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md) - [Landing-landing roll: Loss of control on ground](https://openairdocs.org/ntsb-events/230); cases with it: [Cessna 210N, 1 case](https://openairdocs.org/ntsb-events/230/sequence.md?model=2073453), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Landing-landing roll: Runway excursion](https://openairdocs.org/ntsb-events/300); cases with it: [Cessna 210N, 4 cases](https://openairdocs.org/ntsb-events/300/sequence.md?model=2073453), [All aircraft, 3,643 cases](https://openairdocs.org/ntsb-events/300/sequence.md) ## Analysis The pilot reported a failure of the left brake during the landing roll. The airplane departed the runway surface and impacted a fence, which cause substantial damage to the empennage, right elevator, and horizontal stabilizers. Postaccident examination of the brake system revealed that the left brake master cylinder reservoir was completely empty. It was serviced and tested with no failure or leaks identified. Further examination of the brake system included the removal of the main landing gear pivot trunnion. It revealed that the O-rings, while not visibly damaged, were flat and stiff, which likely allowed the brake fluid to leak out from the main landing gear trunnion to the actuator interface joint when the landing gear was retracted. ## Factual narrative On December 26, 2022, at 1645 mountain standard time, a Cessna 210N, N210CU, was substantially damaged when it was involved in an accident at Morgan County Airport (42U), Morgan, Utah. The pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot of the airplane reported that, after conducting an uneventful flight to Spanish Fork, Utah, he then flew to 42U. He landed normally, and after the nose landing gear touched down, he began to apply the brakes. The pilot stated that the left pedal “had zero pressure” when he applied the brakes, He stated that he pumped the left brake to “pump the brake up,” but that did not work. The pilot stated at that point, there was not enough time to safely reconfigure the airplane for a go-around. He maintained runway centerline with steering and the right brake until the airplane eventually departed the runway surface and impacted a fence. The empennage, right elevator, and horizontal stabilizers sustained substantial damage. The pilot stated that there had been a recurring issue with the left brake and maintenance was performed to correct the malfunction. Since that time, he had flown more than 10 hours with over 25 takeoffs and landings without any issue. The pilot further reported that he did not see hydraulic fluid on the airplane’s undercarriage. Postaccident examination of the brake system revealed that when the left brake was actuated there was no pressure and did not function properly. The right brake operated normally when brake force was applied. The seats and floor panels were removed to facilitate further inspection of the brakes. The left brake master cylinder was removed and disassembled with no evidence of a hydraulic fluid leak of the master cylinder or brake lines in the forward cabin subfloor area. However, the left master cylinder reservoir was completely empty of hydraulic fluid. The O-ring and master cylinder were in a serviceable condition. The brake system was reassembled and serviced with fluid. The left brake was activated with a maximum pressure applied for 5 minutes with no failure or leakages identified. The left landing gear leg and pivot assembly were removed, and the O-rings from the brake fluid transition assembly were undamaged, normally shaped, and flexible to the touch. The main landing gear pivot trunnion was disassembled, and the O-rings did not have visible damage; however, they appeared “flattened and stiff.” There was a significant amount of brake fluid under the aft cabin floor in front of the bulkhead forward of the landing gear door and brake line pivot fitting. ## Aircraft - Registration: [N210CU](https://openairdocs.org/aircraft/N210CU), registered now, S/N 21064452, built 1981 (OpenAirDocs) - Reported make and model: CESSNA 210N - Registry model: [Cessna 210N](https://openairdocs.org/model/cessna-210n) (registry code 2073453) (OpenAirDocs) - Registry engine: [Continental IO-550-F](https://openairdocs.org/engine/continental-io-550-f) (registry code 17211, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 21064452 - Year built: 1981 - Airframe hours: 2501 - Engines: Continental IO-550-F 310 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Condition, September 25, 2022 - Departed: SPK, Spanish Fork, UT - Destination: Same as departure - Airport: 42U, Morgan County, runway 21, 3,904 × 50 ft, asphalt - Equipment: Electronic multifunction display, Electronic flight bag or handheld device, Auto-pilot, ADS-B, Stall warning system, Electronic primary flight display ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 22; injuries: none; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; last flight review April 27, 2022; seat: left; restraint: 3-point; flight hours: 973.2 total, 64.1 in this make and model, 648.6 as pilot in command, 79.2 in the last 90 days, 20.5 in the last 30 days, 3.6 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 41 °F, dew point 34 °F - Altimeter: 30.17 inHg - Observed at: KHIF, 9 nm away - METAR: METAR KHIF 262355Z AUTO 00000KT 10SM CLR 05/01 A3017 RMK AO2 SLP215 T00520006 10079 20034 55014 FZRANO $= ## 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 20221226019859A](https://openairdocs.org/incident/20221226019859A), Dec 26, 2022: Cessna 210N, Morgan, UT, Substantial damage. Pilot made landing at 42U, upon landing pilot found the left brake had no pressure. Pilot determined that there was not enough space to try to take off and… ## Docket (4 files) The files NTSB released with the investigation on June 20, 2024, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=106498. 11.8 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 2.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16251441&FileExtension=pdf&FileName=6120%20N210CU_Redacted-Rel.pdf - Photos (item 2, PDF, 3 pages, 618 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16217299&FileExtension=pdf&FileName=Photos%20WPR23LA076-Rel.pdf - Brake inspection (item 3, PDF, 8 pages, 2.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16217902&FileExtension=pdf&FileName=Brake%20Inspection_Redacted-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 4, PDF, 1 page, 6.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=16217309&FileExtension=pdf&FileName=75495%20Wreckage%20Release_Redacted-Rel.pdf 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.