# NTSB ATL88IA074: Mooney M-20E, N1936Y, Columbia, SC, October 6, 1987

- Type: NTSB incident investigation
- Classification: Incident · No injuries · Incident investigation · Final report
- Date: October 5, 1987, 20:04 local (Oct 6, 1987, 01:04 UTC)
- Place: Columbia, SC
- Coordinates: 33.989673, -81.079048 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=33.9897&lon=-81.0790&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report July 10, 1989
- Report: Approved by Office Director
- NTSB case key (mKey): 7627
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL88IA074
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/7627/pdf
- Page: https://openairdocs.org/ntsb/ATL88IA074

## Sequence of events

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

- Airframe/component/system failure/malfunction, takeoff - roll/run
  - propeller system/accessories - separation (cause)
  - maintenance,installation - improper, other maintenance personnel (cause)

## Analysis

DURING TAKEOFF THE PROPELLER STUDS FAILED AND THE PROPELLER DEPARTED THE ACFT. FAA INCIDENT RPT STATED THAT PROPELLER HAD BEEN OVERHAULED AND REPLACED 32 HOURS PRIOR TO THE SEPARATION. METALLURGICAL EXAM OF THE PROPELLER STUDS REVEALED FATIGUE FAILURE OF THE STUDS THROUGH THE THREADED AREA WITH NO DAMAGE TO THE THREADS. FATIGUE FAILURE OF PROP STUDS OCCURRED AS A RESULT OF VIBRATION DUE TO INADEQUATE TORQUING OF THE MOUNTING NUTS.

## Aircraft

- Registration: [N1936Y](https://openairdocs.org/deregistered/N1936Y-2001-05-31), registration cancelled 2001-05-31, S/N 243 (OpenAirDocs)
- Reported make and model: MOONEY M-20E
- Registry model: [Mooney M20E](https://openairdocs.org/model/mooney-m20e) (registry code 5870212) (OpenAirDocs)
- Category: Airplane
- Serial number: 243
- Airframe hours: 3059
- Engines: LYCOMING IO-360-A1A 200 horsepower reciprocating
- Damage: Minor damage
- Flight: Personal, Part 91
- Operator: Walter Wilder, Jr.
- Registered owner: Walter Wilder, Jr.
- Airworthiness certificate: Standard, Normal
- Airport: CAE, Columbia Metro, runway 29, 8,602 × 150 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 54; private; airplane ratings: single-engine land; seat: left; flight hours: 1,200 total, 600 in this make and model

## Weather

- Conditions: Visual (VMC), Day
- Wind: 190° at 3 knots
- Visibility: 15 statute miles
- Lowest ceiling: none
- Temperature: 61 °F
- Altimeter: 29.00 inHg
- Observed at: CAE

## FAA reports on this event (1)

The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs).

- [Incident 19871005074829I](https://openairdocs.org/incident/19871005074829I), Oct 5, 1987: Mooney M20E, Columbia, SC, Minor damage. Propeller separated from engine on takeoff roll. Aborted. Six attach bolts sheared off. Corrosion on attach bolts.

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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