# NTSB ANC83LA099: Cessna 185, N3991Q, (N) Skwentna, AK, June 18, 1983

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: June 17, 1983, 21:30 local (Jun 18, 1983, 05:30 UTC)
- Place: (N) Skwentna, AK
- Coordinates: 55.259098, -160.660827 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=55.2591&lon=-160.6608&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 4 uninjured
- Status: Completed
- Report: Approved by Office Director
- NTSB office: Alaska Regional Office
- NTSB case key (mKey): 4130
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC83LA099
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/4130/pdf
- Page: https://openairdocs.org/ntsb/ANC83LA099

## Sequence of events

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

- Airframe/component/system failure/malfunction, cruise - normal
  - landing gear,normal brake system - disconnected (contributing factor)
  - landing gear,normal brake system - inoperative (contributing factor)
  - aircraft preflight - inadequate, pilot in command (cause)
- Loss of control - on ground/water, landing - flare/touchdown
  - ground loop/swerve - intentional, pilot in command (cause)

## Analysis

THE ACFT WAS GROUND LOOPED INTENTIONALLY TO PREVENT A COLLISION WITH PEOPLE OR BOATS. THE PILOT SAID HE HAD NO BRAKING ACTION DURING LANDING. HE BELIEVES SOMEONE LOOSENED THE PLUGS IN THE BOTTOM OF BOTH BRAKE CYLINDERS AND THESE PLUGS DROPPED OUT IN FLIGHT. HE SAID BOTH PLUGS WERE IN PLACE DURING PREFLIGHT AND BRAKING WAS GOOD WHILE TAXING FOR TAKEOFF. THE TAPPED THREADS FOR THOSE PLUGS WERE CLEAN AND SHINY DURING POST-ACCIDENT EXAMINATION.

## Aircraft

- Registration: [N3991Q](https://openairdocs.org/deregistered/N3991Q-2012-11-14), registration cancelled 2012-11-14, S/N 18502217, built 1973 (OpenAirDocs)
- Reported make and model: CESSNA 185
- Registry model: [Cessna A185F](https://openairdocs.org/model/cessna-a185f) (registry code 2072821) (OpenAirDocs)
- Registry engine: [Continental IO-520 series](https://openairdocs.org/engine/continental-io-520-series) (registry code 17032, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 1850217
- Airframe hours: 2941
- Engines: CONTINENTAL IO-520-D 205 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Wiley D. Denson
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, August 20, 1982, 56 hours before
- Departed: 215, BIRCHWOOD, AK
- Destination: LAKE CREEK STP., AK
- Airport: Lake Creek, runway 9, 1,000 ×  ft, gravel

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 44; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 500 total, 80 in this make and model, 450 as pilot in command, 30 in the last 90 days, 15 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 20 statute miles
- Lowest ceiling: none
- Temperature: 61 °F, dew point 30 °F

## 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 19830617031159A](https://openairdocs.org/incident/19830617031159A), Jun 17, 1983: Cessna 185, Skwentna, AK, Substantial damage. No brakes on landing. Groung looped to avoid end of runway and parked aircraft. Brake cylinder plugs had fallen out

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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