# NTSB ERA21LA222: Mooney M20K, N9514R, Dawson, GA, May 20, 2021

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Class 3 · Limited · Final report
- Date: May 20, 2021, 09:30 local (13:30 UTC)
- Place: Dawson, GA · 3495 Graves Highway
- Coordinates: 31.771412, -84.50667
- Nearby events: https://openairdocs.org/map.md?lat=31.7714&lon=-84.5067&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Defining event: [Enroute: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341)
- Highest injury: Serious injuries
- Injuries: 2 serious
- Status: Completed
- Report: Approved by Office Director
- Investigation class: Class 3
- NTSB office: Eastern Region Aviation
- Parties: FAA - FSDO
- NTSB case key (mKey): 103119
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA21LA222
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/103119/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=103119
- Page: https://openairdocs.org/ntsb/ERA21LA222

## Probable cause

Maintenance personnel’s failure to properly secure the No. 4 connecting rod bolt nut with a cotter pin, resulting in a total loss of engine power.

## Findings

NTSB's coded findings; those marked are part of the probable cause.

- [Maintenance: replacement](https://openairdocs.org/ntsb-findings/02062020): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Mooney M20K, 1 case](https://openairdocs.org/ntsb-findings/02062020/cases.md?model=5870220), [All aircraft, 70 cases](https://openairdocs.org/ntsb-findings/02062020/cases.md)
- [Engine (reciprocating): recip engine power section](https://openairdocs.org/ntsb-findings/01058520): Aircraft › Aircraft power plant · Incorrect service/maintenance (probable cause); cases with it: [Mooney M20K, 4 cases](https://openairdocs.org/ntsb-findings/01058520/cases.md?model=5870220), [All aircraft, 233 cases](https://openairdocs.org/ntsb-findings/01058520/cases.md)

## Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event best describes what happened.

- [Enroute: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Mooney M20K, 15 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=5870220), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md)
- [Enroute: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Mooney M20K, 14 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=5870220), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md)
- [Enroute: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Mooney M20K, 28 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=5870220), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md)

## Analysis

The pilot reported that, while en route to the destination airport, the airplane lost total engine power. The pilot declared an emergency with air traffic control and began to divert to the nearest airport. The pilot recognized that the airplane would not be able to glide to the airport, and he decided to land on a road with the landing gear and flaps retracted. The pilot and passenger sustained serious injuries, and the airplane was substantially damaged. A postaccident teardown examination of the engine revealed that the No. 4 connecting rod was fractured midspan. One of the No. 4 connecting rod bolt nuts was found in the oil pan and exhibited no signs of pre- or postaccident damage. The cotter pin for that nut was not found; the other No. 4 connecting rod nut was found secured to its bolt with the cotter pin installed. Additionally, all other connecting rod bolt nuts remained attached to their respective bolts with cotter pins in place. Thus, it is likely that the nut found in the oil pan was not secured with a cotter pin and that the unsecured No. 4 connecting rod bolt nut became loose over time and backed out of the connecting rod bolt during the accident flight, resulting in the total loss of engine power. Review of maintenance records revealed that the engine had accumulated about 1,240 hours of operation since major overhaul, which was completed more than 28 years before the accident. The engine manufacturer recommended that the engine be overhauled every 2,000 hours or 12 calendar years, whichever occurred first. The investigation could not determine when the No. 4 connecting rod nut was installed without a cotter pin.

## Factual narrative

On May 20, 2021, about 0930 eastern daylight time, a Mooney M20K, N9514R, was substantially damaged when it was involved in an accident near Dawson Municipal Airport (16J), Dawson, Georgia. The pilot and passenger sustained serious injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. According to the pilot, he had recently purchased the airplane. On the day of the accident, the pilot conducted a preflight inspection with no anomalies noted, and the airplane departed Orlando Apopka Airport (X04), Apopka, Florida, about 0815 for a flight to Birmingham-Shuttlesworth International Airport (BHM), Birmingham, Alabama. While en route to the destination airport, the airplane lost total engine power. The pilot declared an emergency to air traffic control and diverted to the nearest airport, which was 16J. During the descent, the pilot operated the engine controls with no response from the engine. The pilot realized that the airplane would not reach the airport, and he landed the airplane on a road with the landing gear and flaps retracted. The airplane’s right wing and fuselage were substantially damaged. A postaccident teardown examination revealed two holes in the top of the engine crankcase, with the larger hole near the center and the smaller hole just aft. The cylinders remained attached to the crankcase. The No. 4 connecting rod was found fractured about midspan. A No. 4 connecting rod bolt nut was found in the oil pan. This nut exhibited no signs of impact damage or damage that would be consistent with separation. A cotter pin associated with the nut was not located. The other No. 4 connecting rod nut was found secured to its bolt with the cotter pin installed. All other connecting rod bolt nuts remained attached to their respective bolts with cotter pins in place. The oil filter pleats and oil sump contained a large amount of metallic debris. Review of maintenance records revealed that the engine had accumulated about 1,240 hours of operation since its last major overhaul, which was completed on September 18, 1992. The engine manufacturer recommended that the engine be overhauled every 2,000 hours or 12 calendar years, whichever occurred first. Further review of the records revealed that the engine was disassembled, cleaned, and inspected due to a crankcase crack in 2005 and that the No. 3 cylinder was replaced in 2013.

## Aircraft

- Registration: [N9514R](https://openairdocs.org/deregistered/N9514R-2022-12-03), registration cancelled 2022-12-03, S/N 25-0484, built 1980 (OpenAirDocs)
- Reported make and model: MOONEY AIRCRAFT CORP. M20K
- Registry model: [Mooney M20K](https://openairdocs.org/model/mooney-m20k) (registry code 5870220) (OpenAirDocs)
- Registry engine: [Continental TSIO-360 series](https://openairdocs.org/engine/continental-tsio-360-series) (registry code 17019, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 25-0484
- Year built: 1980
- Airframe hours: 3575.7
- Engines: Continental TSIO 360 GB1 210 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, May 27, 2020, 25.8 hours before
- Departed: X04, Apopka, FL
- Destination: BHM, Birmingham, AL
- Equipment: Electronic multifunction display, Electronic primary flight display, Stall warning system, ADS-B, Auto-pilot, Electronic flight bag or handheld device

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 69; injuries: serious; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review March 2, 2021; seat: left; restraint: 3-point; flight hours: 1,030 total, 25 in this make and model, 1,030 as pilot in command, 19 in the last 90 days, 7 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 110° at 17 knots, gusting 23
- Visibility: 10 statute miles
- Temperature: 79 °F, dew point 61 °F
- Altimeter: 30.31 inHg
- Observed at: ABY, 21 nm away
- METAR: KABY 201353Z 11017G23KT 10SM FEW028 26/16 A3031 RMK AO2 SLP262 T02560156

## 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 20210520009589A](https://openairdocs.org/incident/20210520009589A), May 20, 2021: Mooney Aircraft Corp. M20K, Dawson, GA, Substantial damage. On may 20, 2021, at approximately 0945 eastern daylight time, a 1980 Mooney, M20K19, with registration N9514R, sustained major damage while attempting an…

## Other investigations on N9514R (1)

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.

- [NTSB CHI91LA283](https://openairdocs.org/ntsb/CHI91LA283), Aug 31, 1991: Mooney M20K (N9514R), Burlington, WI, substantial damage. Probable cause: THE PILOT'S EXCEEDING THE AIRPLANE'S LICENSED GROSS WEIGHT AND THE PILOT'S IMPROPER PREFLIGHT PLANNING AND PREPARATION.

## Docket (4 files)

The files NTSB released with the investigation on June 22, 2023, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=103119. 6.2 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 2.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15366911&FileExtension=pdf&FileName=6120_redacted-Rel.pdf
- Excerpts from maintenance records (item 2, PDF, 4 pages, 713 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15366614&FileExtension=pdf&FileName=Mx%20Excerpts_Redacted-Rel.pdf
- Photo array (item 3, PDF, 7 pages, 910 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15366624&FileExtension=pdf&FileName=Photo%20Array-Rel.pdf
- Engine examination summary (item 4, PDF, 13 pages, 2.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15424169&FileExtension=pdf&FileName=Exam%20Summary%20ERA21LA222-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.