# NTSB NYC90LA123: Cessna 401, N401FC, Plymouth, MA, May 31, 1990

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: May 31, 1990, 11:15 local (15:15 UTC)
- Place: Plymouth, MA
- Location: 41.9088° N, 70.7276° W: Placed by OpenAirDocs at PLYMOUTH MUNI (PYM), within about a mile (OpenAirDocs)
- Nearby events: https://openairdocs.org/map.md?lat=41.9088&lon=-70.7276&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 23, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 36656
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=NYC90LA123
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/36656/pdf
- Page: https://openairdocs.org/ntsb/NYC90LA123

## Probable cause

IMPROPER MAINTENANCE AND INSPECTION BY MAINTENANCE PERSONNEL OF THE LEFT GEAR TORQUE LINK ATTACHMENT.

## Sequence of events

In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf).

- Gear collapsed, landing - roll
  - landing gear,normal retraction/extension assembly - separation (cause)
  - maintenance,100-hour inspection - improper, other maintenance personnel (cause)
  - maintenance,inspection - improper, other maintenance personnel (cause)
- Loss of control - on ground/water, landing - roll

## Analysis

THE AIRPLANE LANDED NORMALLY. THE PILOT FELT A VIBRATION AND THE AIRPLANE PULLED LEFT DURING ROLLOUT. HE HEARD A LOUD SNAPPING SOUND AND THE LEFT SIDE OF THE AIRPLANE DROPPED TO THE RUNWAY. THE AIRPLANE PULLED SEVERELY LEFT AND DEPARTED THE RUNWAY AND STOPPED IN THE GRASS ABOUT 30 FEET FROM THE RUNWAY. EXAMINATION OF THE LANDING GEAR REVEALED A NUT, WASHER, AND COTTER PIN WERE MISSING FROM THE LEFT GEAR TORQUE-LINK ATTACHMENT TWO HOURS HOBBS TIME AFTER THE ACCIDENT OCCURRED. WORK HAD BEEN PERFORMED ON THE LEFT GEAR TORQUE LINK ATTACHMENT DURING THE LAST INSPECTION.

## Aircraft

- Registration: [N401FC](https://openairdocs.org/deregistered/N401FC-2011-01-03), registration cancelled 2011-01-03, S/N 401-0211, built 1968 (OpenAirDocs)
- Reported make and model: CESSNA 401
- Registry model: [Cessna 401](https://openairdocs.org/model/cessna-401) (registry code 207590C) (OpenAirDocs)
- Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 401-0211
- Engines: CONTINENTAL TSIO-520-E 300 horsepower reciprocating
- Damage: Substantial damage
- Flight: Business, Part 91
- Operator: Plymouth Air Sales
- Airport: PYM, Plymouth, runway 24, 3,500 × 75 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 50; commercial; airplane ratings: single-engine sea, single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--w/ waivers/lim; flight hours: 11,400 total, 400 in this make and model, 11,300 as pilot in command, 50 in the last 90 days, 10 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 225° at 15 knots
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: -0 °F, dew point -0 °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 19900531018239A](https://openairdocs.org/incident/19900531018239A), May 31, 1990: Cessna 401, Plymouth, MA, Substantial damage. Left main landing gear collapsed on landing roll,wing hit. Veered off runway. Torque link not secured by mechanic.

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.

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