# NTSB SEA89FA068: Lake LA-4-200-EP, N8521Z, Bellevue, WA, April 12, 1989

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: April 12, 1989, 10:45 local (17:45 UTC)
- Place: Bellevue, WA
- Coordinates: 47.609626, -122.209419 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=47.6096&lon=-122.2094&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 2 fatal
- Status: Completed, report June 16, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 40916
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA89FA068
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/40916/pdf
- Page: https://openairdocs.org/ntsb/SEA89FA068

## Probable cause

LOSS OF ENGINE POWER FOR AN UNDETERMINED REASON AND FAILURE OF THE INSTRUCTOR PILOT (CFI) TO MAINTAIN CONTROL OF THE AIRCRAFT, WHICH RESULTED IN A STALL/SPIN.

## Sequence of events

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

- Loss of engine power(total) - nonmechanical, takeoff - initial climb
  - reason for occurrence undetermined (cause)
  - ignition system,spark plug - worn
  - maintenance,100-hour inspection - not performed
- Forced landing, descent - emergency
- Loss of control - in flight, descent - emergency
  - aircraft control - not maintained, pilot in command(cfi) (cause)
  - stall/spin - inadvertent, pilot in command(cfi) (cause)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

THE INSTRUCTOR PLT (CFI) HAD BEEN TRAINING THE STUDENT, WHO WAS A CERTIFICATED PLT, BUT NOT SEAPLANE RATED. WITNESSES RPRTD THAT AS THE ACFT DEPARTED LAKE SAMMAMISH, THE ENG MADE UNUSUAL SOUNDS, THEN IT BECAME SILENT. ONE WITNESS RPRTD HESAW THE AIRPLANE SPINNING IN A FLAT ATTITUDE. AN INVESTIGATION REVEALED NO PREIMPACT PART FAILURE, BUT DURING A TEST, THE SPARK PLUGS WOULD NOT FIRE CONTINUOUSLY AT THE MIMIMUM ALLOWABLE OPERATIONAL PRESSURE. THE ACFT HAD BEEN EQUIPPED WITH AN EXTENDED PROPELLER HUB IN ACCORDANCE WITH STC #SA4NE. THIS MODIFICATION EXTENDED THE PROPELLER REARWARD BY 4 INCHES. THE ACFT HAD FLOWN 255 HRS SINCE IT WAS LAST INSPECTED.

## Aircraft

- Registration: [N8521Z](https://openairdocs.org/deregistered/N8521Z-1992-04-27), registration cancelled 1992-04-27, S/N 1093 (OpenAirDocs)
- Reported make and model: LAKE LA-4-200-EP (LA-4-200-E)
- Registry model: [Lake LA-4-200](https://openairdocs.org/model/lake-la-4-200) (registry code 5110310) (OpenAirDocs)
- Category: Airplane
- Serial number: 1093
- Airframe hours: 600
- Engines: LYCOMING IO-360-A1B 200 horsepower reciprocating
- Damage: Destroyed
- Flight: Instructional, Part 91
- Operator: Lake Aircraft
- Registered owner: Starship Leasing Inc.
- Airworthiness certificate: Standard, Normal
- Last inspection: Annual, July 15, 1988, 255 hours before
- Departed: RNT, RENTON, WA

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 23; flight instructor, commercial; airplane ratings: multi-engine land, single-engine sea, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: right; toxicology performed; flight hours: 1,592 total, 1,463 as pilot in command

## Weather

- Conditions: Visual (VMC), Day
- Wind: 10° at 6 knots
- Visibility: 7 statute miles
- Lowest ceiling: 2,500 ft broken
- Temperature: 54 °F, dew point 39 °F
- Altimeter: 30.00 inHg
- Observed at: BFI, 9 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 19890412007819A](https://openairdocs.org/incident/19890412007819A), Apr 12, 1989: Conaer STCLA4, Bellevue, WA, Destroyed, 2 fatal. Wreckage indicates aircraft was in a flat spin at impact. Stalls were scheduled. Flat spins in type poor recovery.

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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