# NTSB ERA19LA006: Cessna 205, N8495Z, Wagoner, OK, October 4, 2018

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Class 3 · Limited · Final report
- Date: October 4, 2018, 18:30 local (23:30 UTC)
- Place: Wagoner, OK
- Coordinates: 35.965557, -95.341941 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=35.9656&lon=-95.3419&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Defining event: [Maneuvering: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed
- Report: Approved by Office Director
- Investigation class: Class 3
- NTSB office: Eastern Region Aviation
- Parties: FAA/FSDO, Continental Motors
- NTSB case key (mKey): 98434
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA19LA006
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/98434/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=98434
- Page: https://openairdocs.org/ntsb/ERA19LA006

## Probable cause

Maintenance personnel’s improper maintenance of the magnetos, which resulted in a loss of engine power.

## Findings

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

- [Ignition system: magneto/distributor](https://openairdocs.org/ntsb-findings/01057414): Aircraft › Aircraft power plant · Not serviced/maintained (probable cause); cases with it: [Cessna 210-5A(205A), 1 case](https://openairdocs.org/ntsb-findings/01057414/cases.md?model=2073204), [All aircraft, 101 cases](https://openairdocs.org/ntsb-findings/01057414/cases.md)
- [Maintenance: scheduled/routine maintenance](https://openairdocs.org/ntsb-findings/02062010): Personnel issues › Task performance · Maintenance personnel (probable cause); cases with it: [Cessna 210-5A(205A), 1 case](https://openairdocs.org/ntsb-findings/02062010/cases.md?model=2073204), [All aircraft, 320 cases](https://openairdocs.org/ntsb-findings/02062010/cases.md)

## Sequence of events

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

- [Maneuvering: Powerplant sys/comp malf/fail](https://openairdocs.org/ntsb-events/340) (defining event); cases with it: [Cessna 210-5A(205A), 1 case](https://openairdocs.org/ntsb-events/340/sequence.md?model=2073204), [All aircraft, 820 cases](https://openairdocs.org/ntsb-events/340/sequence.md)
- [Maneuvering: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341); cases with it: [Cessna 210-5A(205A), 2 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=2073204), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md)
- [Emergency descent: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Cessna 210-5A(205A), 2 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=2073204), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md)

## Analysis

During a post maintenance flight after the airplane's annual inspection, the pilot made about three circuits around the airport area before departing to continue flight maneuvers and performance checks. He started a left turn and then noticed a “very minor engine mis[fire]." As the pilot continued the turn, the "engine mis[fire]" began to increase and the engine began to shake. The airplane was unable to maintain altitude and was descending about 150-300 ft per minute. Although the pilot made multiple attempts to regain engine power, the engine lost total power. The airplane impacted trees and brush; during the landing sequence, the left and right wings buckled. Following the accident, an engine run was performed; after running for 13 minutes, the engine lost power. Troubleshooting of the magnetos found that the right magneto was firing erratically. The right magneto was replaced with a known-good magneto and the engine was subsequently successfully test run at full power. More detailed testing of both magnetos revealed that they failed the manufacturer’s acceptance test procedures due to excessive point gaps and secondary coil resistance. A review of the engine logbooks revealed the magneto points and condensers were replaced about 18 years and about 230 flight hours before the accident flight. Given the available information, it is likely that maintenance personnel did not perform proper maintenance of the magnetos.

## Factual narrative

On October 4, 2018, about 1830 central daylight time, a Cessna 205A, N8495Z, was substantially damaged when it was involved in an accident near Wagoner, Oklahoma. The pilot sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 flight test. According to the pilot, he was performing a post maintenance flight test. After a routine engine run-up with no abnormal indications, he departed Hefner-Easley Airport (H68), Wagoner, Oklahoma. The pilot climbed to about 2,500 ft mean sea level and made about three circuits around the airport area; he stated that the airplane climbed well and that all flight parameters were normal. The pilot announced his intentions of leaving the airport area and turned south to continue flight maneuvers and performance checks. The pilot started a left turn when a “very minor engine mis[fire]" occurred. He scanned the instrument panel, and all engine parameters appeared normal. As the pilot continued the turn, the "engine mis[fire]" began to increase and the engine began to shake. The airplane was unable to maintain altitude and was descending about 150-300 ft per minute. The pilot made multiple attempts to regain engine power, but the engine then lost total power. The pilot slowed the airplane to the minimum controllable airspeed and impacted trees and brush. During the landing sequence, the left and right wings buckled. A postaccident engine run was performed and revealed that, after running for 13 minutes, the engine lost power and the No. 6 cylinder began to significantly cool. Troubleshooting of the magnetos found that the right magneto was firing erratically. The right magneto was replaced with a known-good magneto and the engine was subsequently successfully test run at full power. The accident magnetos were removed for testing, and both magnetos failed the manufacturer’s acceptance test procedure due to excessive point gaps and secondary coil resistance. Additionally, both magnetos did not produce output until above 3,000 rpm. A review of the engine logbooks revealed the magneto points and condensers were replaced in both magnetos on September 20, 2000, at a tachometer time of 786.5 hours. There were no logbook entries detailing a magneto 500-hour inspection. Since the repair of the magnetos, the engine had accumulated about 233.3 hours prior to the accident flight.

## Aircraft

- Registration: [N8495Z](https://openairdocs.org/deregistered/N8495Z-2022-05-09), registration cancelled 2022-05-09, S/N 2050495, built 1963 (OpenAirDocs)
- Reported make and model: Cessna 205 (A)
- Registry model: [Cessna 210-5A(205A)](https://openairdocs.org/model/cessna-210-5a-205a) (registry code 2073204) (OpenAirDocs)
- Registry engine: [Continental I0-470 series](https://openairdocs.org/engine/continental-i0-470-series) (registry code 17027, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 2050495
- Year built: 1963
- Airframe hours: 3862.74
- Engines: Continental IO-470S 260 horsepower reciprocating
- Damage: Substantial damage
- Flight: Flight test, Part 91
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, March 31, 2018, 1 hours before
- Departed: H68, Wagoner, OK
- Destination: H68, Wagoner, OK
- Airport: H68, Hefner-Easley, runway 18, 3,401 × 60 ft, asphalt
- Equipment: Stall warning system

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 61; injuries: minor; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; last flight review September 17, 2017; seat: left; restraint: lap only; flight hours: 1,450 total, 2 in this make and model, 1,377 as pilot in command, 26 in the last 90 days, 14 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 160° at 4 knots
- Visibility: 10 statute miles
- Lowest ceiling: none
- Temperature: 81 °F, dew point 68 °F
- Altimeter: 29.95 inHg
- Observed at: KTQH, 16 nm away

## 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 20181004019469A](https://openairdocs.org/incident/20181004019469A), Oct 4, 2018: Cessna 210-5A(205A), Wagoner, OK, Substantial damage. On October 4, 2018 at approximately 6:30 local time, pilot flew aircraft from Hefner-Easley Airport (H68) for a post maintenance test flight. All went normal…

## Other investigations on N8495Z (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 MKC76DCQ77](https://openairdocs.org/ntsb/MKC76DCQ77), Sep 19, 1976: Cessna 205 (N8495Z), Winona, KS, substantial damage

## Docket (6 files)

The files NTSB released with the investigation on January 20, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=98434. 18.0 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 6.4 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9378173&FileExtension=pdf&FileName=NTSB%206120_1%20Form_Redacted-Rel.pdf
- Pilot's statement (item 2, PDF, 2 pages, 140 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9377695&FileExtension=pdf&FileName=Crash%20statement%20-%20revised_Redacted-Rel.pdf
- Maintenance records (item 3, PDF, 13 pages, 10.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9377886&FileExtension=pdf&FileName=Logbooks%20excepts%20LA006_Redacted-Rel.pdf
- Magneto test report (item 4, PDF, 1 page, 395 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9377966&FileExtension=pdf&FileName=NTSB%20-%20findings%20of%20mags%20removed%20from%20N8495Z%20June%2012th,%202019_Redacted-Rel.pdf
- Photo array (item 5, PDF, 1 page, 410 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9377704&FileExtension=pdf&FileName=Photo%20Array%20LA006-Rel.pdf
- Statement of party representatives to NTSB investigation (item 6, PDF, 10 pages, 686 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9377607&FileExtension=pdf&FileName=CMG%20Party%20Form_Redacted-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.

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