# NTSB CEN16LA356: Cessna P210N, N323DC, Waco, TX, August 5, 2016 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: August 5, 2016, 17:00 local (22:00 UTC) - Place: Waco, TX - Coordinates: 31.612222, -97.230278 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=31.6122&lon=-97.2303&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-flare/touchdown: Landing gear collapse](https://openairdocs.org/ntsb-events/094) - Highest injury: No injuries - Injuries: 5 uninjured - Status: Completed, report January 25, 2018 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA -- Flight Standards - NTSB case key (mKey): 93960 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN16LA356 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/93960/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=93960 - Page: https://openairdocs.org/ntsb/CEN16LA356 ## Probable cause The failure of the right main landing gear (MLG) down-lock mechanism, which resulted in the collapse of the landing gear. The root cause of the right MLG down-lock mechanism could not be determined because the components were not available for examination. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Landing gear system: gear extension and retract sys](https://openairdocs.org/ntsb-findings/01023230): Aircraft › Aircraft systems · Failure (probable cause); cases with it: [Cessna P210N, 12 cases](https://openairdocs.org/ntsb-findings/01023230/cases.md?model=2073454), [All aircraft, 416 cases](https://openairdocs.org/ntsb-findings/01023230/cases.md) - [Electrical power system: dC generator-alternator](https://openairdocs.org/ntsb-findings/01022434): Aircraft › Aircraft systems · Failure; cases with it: [Cessna P210N, 2 cases](https://openairdocs.org/ntsb-findings/01022434/cases.md?model=2073454), [All aircraft, 5 cases](https://openairdocs.org/ntsb-findings/01022434/cases.md) - [Electrical power system: dC regulator](https://openairdocs.org/ntsb-findings/01022436): Aircraft › Aircraft systems · Failure; cases with it: [Cessna P210N, 1 case](https://openairdocs.org/ntsb-findings/01022436/cases.md?model=2073454), [All aircraft, 4 cases](https://openairdocs.org/ntsb-findings/01022436/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Electrical system malf/failure](https://openairdocs.org/ntsb-events/332); cases with it: [Cessna P210N, 7 cases](https://openairdocs.org/ntsb-events/332/sequence.md?model=2073454), [All aircraft, 182 cases](https://openairdocs.org/ntsb-events/332/sequence.md) - [Landing-flare/touchdown: Landing gear collapse](https://openairdocs.org/ntsb-events/094) (defining event); cases with it: [Cessna P210N, 21 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=2073454), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) - [Landing-flare/touchdown: Runway excursion](https://openairdocs.org/ntsb-events/300); cases with it: [Cessna P210N, 12 cases](https://openairdocs.org/ntsb-events/300/sequence.md?model=2073454), [All aircraft, 3,643 cases](https://openairdocs.org/ntsb-events/300/sequence.md) ## Analysis The airline transport pilot reported that the electrical system began to indicate a discharge condition during cruise flight and that he chose to divert to an intermediate airport. He lowered the wing flaps and landing gear, and then the airplane lost total electrical power. Landing gear extension seemed to be normal, which included a green down position indicator light and visual verification of the landing gear in the extended position. The pilot then conducted a visual approach to landing, and after landing, the right main landing gear (MLG) collapsed, which resulted in a runway excursion. A postaccident examination of the electrical system revealed that the alternator was not functioning properly and that the voltage regulator was inoperative, which precipitated the diverted landing. Examination of the landing gear system revealed that the right MLG down-lock mechanism had failed. None of the components were provided to the National Transportation Safety Board for further examination, which precluded a determination of the root cause of the failure of the right MLG down-lock mechanism. ## Factual narrative On August 5, 2016, about 1700 central daylight time, a Cessna P210N airplane, N323DC, was substantially damaged when the landing gear collapsed during landing on runway 19 (7,107 feet by 150 feet, concrete) at the Waco Regional Airport (ACT), Waco, Texas. The pilot and four passengers onboard were not injured. The airplane was registered to and operated by the pilot under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed for the flight, which was operated on an instrument flight rules flight plan. The flight originated from the Dallas-Fort Worth International Airport (DFW) about 1630. The intended destination was the Austin-Bergstrom International Airport (AUS), Austin, Texas.The pilot reported that the airplane electrical system began to indicate a discharge condition during cruise flight. He elected to divert to ACT. The wing flaps and landing gear were lowered before the airplane lost electrical power completely. Landing gear extension seemed to be normal, which included a green down position indicator light and visual verification of the landing gear in the extended position. He executed an uneventful visual approach and landing touchdown. However, after touching down, the landing gear collapsed. The airplane subsequently departed the left side of the runway before coming to rest. A postaccident examination of the aircraft electrical system revealed that the alternator was not functioning properly and the voltage regulator was inoperative. Examination of the landing gear system revealed that the right main landing gear down lock mechanism had failed. None of the components were provided to the NTSB for further examination, which precluded any determination of the root cause of the failures. The alternator was repaired and the voltage regulator was replaced. The landing gear down lock mechanism was repaired. The airplane was subsequently returned to service and no further anomalies were reported to the NTSB. ## Aircraft - Registration: [N323DC](https://openairdocs.org/aircraft/N323DC), registered now, S/N P21000384 (OpenAirDocs) - Reported make and model: CESSNA P210N - Registry model: [Cessna P210N](https://openairdocs.org/model/cessna-p210n) (registry code 2073454) (OpenAirDocs) - Registry engine: [Continental TSIO-520 series](https://openairdocs.org/engine/continental-tsio-520-series) (registry code 17040, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: P21000384 - Year built: 1979 - Airframe hours: 6160 - Engines: Continental Motors TSIO-520-P5 310 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, September 8, 2015, 110 hours before - Departed: KDFW, Dallas-Ft Worth, TX - Destination: KAUS, Austin, TX - Flight plan: IFR - Airport: KACT, Waco Regional, runway 19, 7,107 × 150 ft, concrete - Equipment: Electronic primary flight display, Electronic multifunction display, Auto-pilot, ADS-B, Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 62; injuries: none; airline transport; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review April 25, 2016; seat: left; restraint: 3-point; flight hours: 12,108 total, 110 in this make and model, 2,860 as pilot in command, 103 in the last 90 days, 22 in the last 30 days, 0 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 100 °F, dew point 64 °F - Altimeter: 29.89 inHg - Observed at: KACT ## 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 20160805024919A](https://openairdocs.org/incident/20160805024919A), Aug 5, 2016: Cessna P210N, Waco, TX, Substantial damage. The 14 CFR 91 instrument flight originated from dfw in VMC conditions bound for aus. As the flight approached Waco, TX the pilot noticed the alternator had… ## Docket (4 files) The files NTSB released with the investigation on November 20, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=93960. 2.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 857 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40458217&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Conversation Summary - Pilot (item 2, .PDF, 115 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40458218&FileExtension=.PDF&FileName=Conversation%20Summary%20-%20Pilot-Master.PDF - Maintenance Facility Statement (item 3, .PDF, 125 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40458219&FileExtension=.PDF&FileName=Maintenance%20Facility%20Statement-Master.PDF - Pilot's Operating Handbook - Excerpt (item 4, .PDF, 1.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40458220&FileExtension=.PDF&FileName=Pilot%27s%20Operating%20Handbook%20-%20Excerpt-Master.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.