# NTSB CEN14CA310: Cessna 421A, N936U, Dallas, TX, May 24, 2014 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: May 24, 2014, 07:15 local (12:15 UTC) - Place: Dallas, TX - Coordinates: 32.737777, -96.969169 - Nearby events: https://openairdocs.org/map.md?lat=32.7378&lon=-96.9692&mi=10 - Phase of flight: [Taxi](https://openairdocs.org/ntsb-phases/250) (OpenAirDocs' grouping) - Defining event: [Taxi-to runway: Landing gear collapse](https://openairdocs.org/ntsb-events/094) - Highest injury: No injuries - Injuries: 4 uninjured - Status: Completed, report September 2, 2014 - Report: Approved by Office Director - NTSB office: Central Region - Parties: FAA North Texas FSDO - NTSB case key (mKey): 89518 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN14CA310 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/89518/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=89518 - Page: https://openairdocs.org/ntsb/CEN14CA310 ## Probable cause The improper rigging of the landing gear by maintenance personnel, which resulted in the landing gear collapse. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Maintenance: scheduled/routine maintenance](https://openairdocs.org/ntsb-findings/02062010): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Cessna 421A, 1 case](https://openairdocs.org/ntsb-findings/02062010/cases.md?model=2076012), [All aircraft, 320 cases](https://openairdocs.org/ntsb-findings/02062010/cases.md) - [Landing gear system](https://openairdocs.org/ntsb-findings/01023200): Aircraft › Aircraft systems · Incorrect service/maintenance (probable cause); cases with it: [Cessna 421A, 1 case](https://openairdocs.org/ntsb-findings/01023200/cases.md?model=2076012), [All aircraft, 113 cases](https://openairdocs.org/ntsb-findings/01023200/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Taxi: Aircraft maintenance event](https://openairdocs.org/ntsb-events/040); cases with it: [Cessna 421A, 1 case](https://openairdocs.org/ntsb-events/040/sequence.md?model=2076012), [All aircraft, 484 cases](https://openairdocs.org/ntsb-events/040/sequence.md) - [Taxi-to runway: Landing gear collapse](https://openairdocs.org/ntsb-events/094) (defining event); cases with it: [Cessna 421A, 2 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=2076012), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) - [Taxi-to runway: Dragged wing/rotor/float/other](https://openairdocs.org/ntsb-events/093); cases with it: [Cessna 421A, 1 case](https://openairdocs.org/ntsb-events/093/sequence.md?model=2076012), [All aircraft, 319 cases](https://openairdocs.org/ntsb-events/093/sequence.md) ## Analysis The pilot, with three passengers, proceeded toward the runway for departure, in a twin-engine airplane. As the airplane approached the taxiway intersection, the right main landing gear collapsed, causing the right wing tank and right engine propeller to impact the ground. Examination of the airplane revealed substantial damage to the right wing and damage to the right engine propeller. Further examination of the landing gear revealed that the gear was not properly rigged. ## Factual narrative The pilot, with three passengers, proceeded toward the runway for departure, in a twin-engine airplane. As the airplane approached the taxiway intersection, the right main landing gear collapsed, causing the right wing tank and right engine propeller to impact the ground. Examination of the airplane revealed substantial damage to the right wing and damage to the right engine propeller. Further examination of the landing gear revealed that the gear was not properly rigged. ## Aircraft - Registration: [N936U](https://openairdocs.org/deregistered/N936U-2018-02-07), registration cancelled 2018-02-07, S/N 421A0065, built 1969 (OpenAirDocs) - Reported make and model: CESSNA 421A - Registry model: [Cessna 421A](https://openairdocs.org/model/cessna-421a) (registry code 2076012) (OpenAirDocs) - Registry engine: [Continental GTSIO-520-C](https://openairdocs.org/engine/continental-gtsio-520-c) (registry code 17035, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 421A0065 - Year built: 1969 - Engines: CONT MOTOR GTSIO-520-C 340 horsepower reciprocating; CONT MOTOR GTSIO-520-C 340 horsepower reciprocating - Damage: Substantial damage - Flight: Business, Part 91 - Operator: Amigo Banding Services Inc - Registered owner: Amigo Banding Services Inc - Airworthiness certificate: Standard, Normal - Departed: KRBD, Dallas, TX - Destination: Kissimee, FL - Flight plan: IFR - Airport: KRBD, Dallas Executive ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 53; injuries: none; airline transport, commercial; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane, helicopter; medical: class 2, without waivers/limitations; last flight review March 2, 2014; seat: left; restraint: lap only; flight hours: 20,000 total, 1,500 in this make and model ## Weather - Conditions: Visual (VMC), Day - Visibility: 10 statute miles - Lowest ceiling: none ## 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 20140524020129A](https://openairdocs.org/incident/20140524020129A), May 24, 2014: Cessna 421A, Dallas, TX, Substantial damage. The ATP rated pilot and his three passengers taxied from parking at Dallas executive airport (rdb) on AN14 CFR part 91, IFR clearance to the assigned runway,… ## Docket (1 files) The files NTSB released with the investigation on August 25, 2014, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=89518. 4.9 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 4.9 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40415633&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.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.