# NTSB ATL93LA011: Cessna 172RG, N9797B, Clarksville, TN, October 15, 1992

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: October 15, 1992, 14:09 local (19:09 UTC)
- Place: Clarksville, TN
- Coordinates: 36.57077, -87.419677 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=36.5708&lon=-87.4197&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 2 uninjured
- Status: Completed, report June 21, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 8694
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ATL93LA011
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/8694/pdf
- Page: https://openairdocs.org/ntsb/ATL93LA011

## Probable cause

THE FRACTURE OF THE SECTION GEAR IN THE MAIN LANDING GEAR RETRACTION AND EXTENSION MECHANISM.

## Sequence of events

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

- Main gear collapsed, landing - flare/touchdown
  - landing gear,normal retraction/extension assembly - fractured (cause)
- On ground/water encounter with terrain/water, landing - roll

## Analysis

THE FLIGHT WAS A LOCAL TRAINING FLIGHT. AT THE COMPLETION OF THE FLIGHT, AS THE PILOT ATTEMPTED TO LOWER THE LANDING GEAR, THE LEFT MAIN LANDING GEAR WOULD NOT EXTEND TO THE LOCKED POSITION. INVESTIGATION OF THE LANDING AND RETRACTION MECHANISM REVEALED THAT THE SECTION GEAR IN THE PIVOT ASSEMBLY HAD SHEARED.

## Aircraft

- Registration: [N9797B](https://openairdocs.org/deregistered/N9797B-2016-11-28), registration cancelled 2016-11-28, S/N 172RG1044, built 1982 (OpenAirDocs)
- Reported make and model: CESSNA 172RG
- Registry model: [Cessna 172RG](https://openairdocs.org/model/cessna-172rg) (registry code 2072438) (OpenAirDocs)
- Registry engine: [Lycoming 0-360-A1D](https://openairdocs.org/engine/lycoming-0-360-a1d) (registry code 41504, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 172RG1044
- Engines: LYCOMING O-360-F1A6 180 horsepower reciprocating
- Damage: Substantial damage
- Flight: Instructional, Part 91
- Operator: Volunteer Flight Training
- Registered owner: Semler, Lanny R.
- Airworthiness certificate: Standard, Normal
- Last inspection: AAIP, January 2, 2000, 70 hours before
- Departed: CKV
- Airport: CKV, Outlaw Field, runway 23, 4,000 × 100 ft, concrete

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 30; commercial, flight instructor; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--w/ waivers/lim; seat: left; flight hours: 1,830 total, 170 in this make and model, 1,800 as pilot in command, 150 in the last 90 days, 50 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 180° at 10 knots, gusting 20
- Visibility: 7 statute miles
- Lowest ceiling: 10,000 ft broken
- Temperature: 77 °F, dew point 61 °F
- Altimeter: 30.00 inHg
- Observed at: HOP, 1 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 19921015042269A](https://openairdocs.org/incident/19921015042269A), Oct 15, 1992: Cessna 172RG, Clarksville, TN, Substantial damage. Left main gear failed lock down and collapsed landing. Landing gear pivot assembly had sheared.

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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