# NTSB SEA86FA033: Mooney M20K, N1152T, Des Moines, WA, December 30, 1985

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: December 29, 1985, 18:13 local (Dec 30, 1985, 02:13 UTC)
- Place: Des Moines, WA
- Coordinates: 47.439414, -122.280708 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.4394&lon=-122.2807&mi=10
- Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 4 fatal
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 40261
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA86FA033
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40261/pdf
- Page: https://openairdocs.org/ntsb/SEA86FA033

## Analysis

THE WEATHER BRIEFER INFORMED THE PILOT THAT VFR WAS NOT RECOMMENDED DUE TO CURRENT/FORECAST CONDTIONS. THE NON INSTRUMENT RATED PILOT THEN FILED A VFR FLIGHT PLAN RESPONDING THAT HE WAS IFR RATED AND WOULD FILE INFLIGHT IF NECESSARY. WITNESSES REPORTED OBSERVING THE AIRCRAFT CRUISING NORTHBOUND OVER I-5 AT A MODERATE SPEED AND LOW ALTITUDE BENEATH THE CLOUDS. WEATHER CONDITIONS IN THE VICINITY OF THE ACCIDENT SITE WERE DESCRIBED AS 300 FOOT CEILING AND 1 MILE VISIBILITY. DARK NIGHT CONDITIONS EXISTED WHEN THE AIRCRAFT STRUCK POWER LINE 75 FEET ABOVE THE I-5 MEDIAN AND 6 NAUTICAL MILES SOUTH OF THE DESTINATION AIRPORT. IN SPITE OF DETERIORATING WEATHER CONDITIONS THE PILOT MADE NO ATTEMPT TO DIVERT ALONG HIS ROUTE OF FLIGHT TO A MORE FAVORABLE DESTINATION. AN ENTRY REFERRING TO 'SCUD FLYING' WAS NOTED IN THE PILOT'S LOGBOOK.

## Sequence of events

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

- In flight collision with object, cruise - normal
  - preflight briefing service - disregarded, pilot in command (cause)
  - overconfidence in personal ability, pilot in command (contributing factor)
  - in-flight planning/decision - improper, pilot in command (cause)
  - lack of recent experience, pilot in command (contributing factor)
  - weather condition - low ceiling (contributing factor)
  - light condition - dark night (contributing factor)
  - object - wire,transmission (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled
- In flight collision with terrain/water, descent - uncontrolled

## Aircraft

- Registration: [N1152T](https://openairdocs.org/deregistered/N1152T-2013-06-04), registration cancelled 2013-06-04, S/N 25-0630, built 1981 (OpenAirDocs)
- Reported make and model: Mooney 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: 250630
- Airframe hours: 1052
- Engines: CONTINENTAL TSIO-360-GB 210 horsepower reciprocating
- Damage: Destroyed
- Flight: Personal, Part 91
- Operator: Sunwest Aviation, Inc., doing business as Snohomish County Airport
- Registered owner: Horst E. Lux
- Airworthiness certificate: Standard, Normal
- Last inspection: 100 hour, December 9, 1985, 81 hours before
- Departed: HIO, HILLSBORO, OR
- Destination: BFI, SEATLE, WA
- Flight plan: VFR

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 31; private; airplane ratings: single-engine land; medical: class 2, valid medical--no waivers/lim.; toxicology performed; flight hours: 341 total, 36 in this make and model, 3 in the last 90 days, 3 in the last 30 days, 3 in the last 24 hours

## Weather

- Conditions: Instrument (IMC), Night/dark
- Wind: 260° at 4 knots
- Visibility: 1 statute miles
- Lowest ceiling: 300 ft broken
- Temperature: 41 °F, dew point 39 °F
- Altimeter: 30.00 inHg
- Observed at: SEA, 2 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 19851229063799A](https://openairdocs.org/incident/19851229063799A), Dec 29, 1985: Mooney M20K, Des Moines, WA, Destroyed, 2 fatal. Struck powerlines then ground while scud running at a very low altitude. No mechanical malfunction found.

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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