# NTSB CEN24LA315: Grumman American Avn. AA-5B, N23JK, Camdenton, MO, July 11, 2024

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Class 3 · Limited · Final report
- Date: July 11, 2024, 10:00 local (15:00 UTC)
- Place: Camdenton, MO
- Coordinates: 37.972668, -92.689197
- Nearby events: https://openairdocs.org/map.md?lat=37.9727&lon=-92.6892&mi=10
- Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping)
- Defining event: [Takeoff: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330)
- Highest injury: No injuries
- Injuries: 3 uninjured
- Status: Completed
- Report: Approved by Office Director
- Investigation class: Class 3
- NTSB office: Central Region
- Parties: FAA
- NTSB case key (mKey): 194929
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=CEN24LA315
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/194929/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=194929
- Page: https://openairdocs.org/ntsb/CEN24LA315

## Probable cause

The inadequate maintenance of the seat locking mechanism, which resulted in the pilot’s seat sliding back during takeoff and a subsequent loss of control.

## Findings

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

- [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Attain/maintain not possible (probable cause); cases with it: [Grumman American Avn. AA-5B, 6 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=3960105), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md)
- [Equipment/furnishings: flight compartment equipment](https://openairdocs.org/ntsb-findings/01022510): Aircraft › Aircraft systems · Fatigue/wear/corrosion (probable cause); cases with it: [Grumman American Avn. AA-5B, 1 case](https://openairdocs.org/ntsb-findings/01022510/cases.md?model=3960105), [All aircraft, 37 cases](https://openairdocs.org/ntsb-findings/01022510/cases.md)
- [Maintenance/inspections](https://openairdocs.org/ntsb-findings/01010500): Aircraft › Aircraft handling/service · Not serviced/maintained; cases with it: [Grumman American Avn. AA-5B, 1 case](https://openairdocs.org/ntsb-findings/01010500/cases.md?model=3960105), [All aircraft, 103 cases](https://openairdocs.org/ntsb-findings/01010500/cases.md)

## Sequence of events

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

- [Takeoff: Sys/Comp malf/fail (non-power)](https://openairdocs.org/ntsb-events/330) (defining event); cases with it: [Grumman American Avn. AA-5B, 2 cases](https://openairdocs.org/ntsb-events/330/sequence.md?model=3960105), [All aircraft, 994 cases](https://openairdocs.org/ntsb-events/330/sequence.md)
- [Takeoff-rejected takeoff: Runway excursion](https://openairdocs.org/ntsb-events/300); cases with it: [Grumman American Avn. AA-5B, 7 cases](https://openairdocs.org/ntsb-events/300/sequence.md?model=3960105), [All aircraft, 3,643 cases](https://openairdocs.org/ntsb-events/300/sequence.md)

## Analysis

During the takeoff roll the pilot’s seat suddenly slid backward, and she was unable to reach the pedals, which resulted in a loss of control and runway excursion. Examination of the airplane revealed substantial damage to the engine mount, fuselage, and horizontal stabilizer. The pilot’s seat tracks were a newer heat-treated version. There were wear marks on the seat lock pin tip indicative of previous alignment issues. The spring that held the lock pins in place was installed incorrectly and the corresponding push-pull rod was bent. This incorrect spring placement shortened the travel of the spring and reduced the tension on the lock pins. The seat brackets that attach to the spar exhibited worn and elongated bolt holes, which created a misalignment of the seat support. It’s likely that the condition of the seat locking mechanism prevented the seat from locking correctly, which resulted in the seat sliding back during takeoff. A review of the available airframe maintenance records did not reveal any entries regarding inspections or work performed on the seats or the seat tracks. The investigation was unable to determine when the pilot’s seat was last inspected, when the lock pin spring was incorrectly installed, and by whom.

## Factual narrative

On July 11, 2024, about 1000 central daylight time, a Grumman AA-5B airplane, N23JK, was substantially damaged when it was involved in an accident near Camdenton, Missouri. The pilot and two passengers were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that before starting the engine, she adjusted her seat to the appropriate position to reach the flight controls, and then wiggled the seat to ensure it was secure. After taxiing to the runway, she wiggled her seat again and prepared for takeoff. During the takeoff roll her seat suddenly slid backward, and she was no longer able to reach the pedals. The airplane departed the side of the runway and came to rest upright in a ravine. Examination of the airplane revealed substantial damage to the engine mount, fuselage, and horizontal stabilizer. The pilot’s seat tracks were a newer heat-treated version. There were wear marks on the seat lock pin tip indicative of previous alignment issues. The spring that held the lock pins in place was installed incorrectly and the corresponding push-pull rod was bent. The seat brackets that attach to the spar exhibited worn and elongated bolt holes, which created a misalignment of the seat support. The most recent annual inspection was completed on January 8, 2024, at airframe total time of 4,423.7 hours. A review of the available airframe maintenance records did not reveal any entries regarding inspections or work performed on the seats or the seat tracks.

## Aircraft

- Registration: [N23JK](https://openairdocs.org/aircraft/N23JK), registered now, S/N AA5B-0022, built 1975 (OpenAirDocs)
- Reported make and model: GRUMMAN AMERICAN AVN. CORP. AA-5B
- Registry model: [Grumman American Avn. AA-5B](https://openairdocs.org/model/grumman-american-avn-aa-5b) (registry code 3960105) (OpenAirDocs)
- Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: AA5B-0022
- Year built: 1975
- Airframe hours: 4423.7
- Engines: Lycoming O-360-A4K 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, January 8, 2024
- Airport: OZS, Camdenton Meml-Lake Rgnl, runway 15/33, 5,002 × 75 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 47; injuries: none; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review February 24, 2024; seat: left; restraint: 3-point; flight hours: 113 total, 49 in this make and model, 71 as pilot in command, 12 in the last 90 days, 3 in the last 30 days, 0 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 10 statute miles
- Lowest ceiling: 10,000 ft broken
- Temperature: 77 °F, dew point 64 °F
- Altimeter: 30.10 inHg
- Observed at: KOZS
- METAR: METAR KOZS 111715Z AUTO 00000KT 10SM BKN100 25/18 A3010 RMK AO2 LTG DSNT NE=

## 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 20240711012419A](https://openairdocs.org/incident/20240711012419A), Jul 11, 2024: Grumman American Avn. Corp. AA-5B, Camdenton, MO, Substantial damage. Pilot reported that upon brake release and applying full power for take-off, her seat slid all the way back to the "full back" position. The pilot was…

## Docket (6 files)

The files NTSB released with the investigation on February 26, 2025, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=194929. 44.7 MB in all.

- Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 5.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17848293&FileExtension=pdf&FileName=6120%20-%20pilot_Redacted-Rel.pdf
- Correspondence - pilot (item 2, PDF, 3 pages, 803 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17848303&FileExtension=pdf&FileName=Pilot%20emails_Redacted-Rel.pdf
- Correspondence - airplane owner (item 3, PDF, 1 page, 69 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18051150&FileExtension=pdf&FileName=ROC%20-%20airplane%20owner%202-Rel.pdf
- Fletchair email summary (item 4, PDF, 3 pages, 745 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=18050151&FileExtension=pdf&FileName=FletchAir%20exam%20summary%20email_Redacted2-Rel.pdf
- Photos (item 5, PDF, 16 pages, 15 photos, 3.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17848400&FileExtension=pdf&FileName=Docket%20photos-Rel.pdf
- Maintenance records (item 6, PDF, 5 pages, 34.1 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=17848723&FileExtension=pdf&FileName=Mx%20logs_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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