# NTSB MIA91FA014: Daniel S. Taylor Sonerai II LS, N148DT, Prattville, AL, October 21, 1990

- Type: NTSB accident investigation
- Classification: Accident · Fatal · Field investigation · Final report
- Date: October 21, 1990, 17:05 local (22:05 UTC)
- Place: Prattville, AL
- Coordinates: 32.510269, -86.559486 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=32.5103&lon=-86.5595&mi=10
- Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping)
- Highest injury: Fatal
- Injuries: 1 fatal
- Status: Completed, report November 23, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 32734
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=MIA91FA014
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/32734/pdf
- Page: https://openairdocs.org/ntsb/MIA91FA014

## Probable cause

THE PILOT'S FAILURE TO MAINTAIN AIRSPEED. FACTORS WERE UNDETERMINED LOSS OF ENGINE POWER AND LACK OF EXPERIENCE IN TYPE.

## Sequence of events

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

- Loss of engine power, takeoff - initial climb
  - fuel system,carburetor - undetermined (contributing factor)
- Loss of control - in flight, maneuvering - turn to landing area (emergency)
  - airspeed(vs) - not maintained, pilot in command (cause)
  - stall/spin - inadvertent, pilot in command
  - lack of total experience in type of aircraft, pilot in command (contributing factor)
- In flight collision with terrain/water, descent - uncontrolled

## Analysis

DURING THE PREVIOUS 4 MOS, THE ENG WAS EXPERIENCING A HOTTER CYLINDER HEAD TEMP OF THE LT REAR CYLINDER THAN THE RT. THE ENG COWLING WAS MODIFIED TO CORRECT THIS BUT THE PROBLEM CONTINUED. THE CYLINDER HEADS WHICH WERE PREVIOUSLY REMOVED WERE INSTALLED THE DAY BEFORE THE ACCIDENT. THE ENG WAS RUN FOR 30 MINUTES WITH NO DISCREPANCIES NOTED. THE MORNING OF THE ACCIDENT, THE ACFT WAS SERVICED WITH FUEL, THE ENG WAS CHECKED, & THE ACFT WAS FLOWN TWICE AROUND THE TRAFFIC PATTERN. THE TEMP PROBLEM CONTINUED. ATTEMPTS TO CORRECT THIS WERE UNSUCCESSFUL DURING A SUBSEQUENT FLT AROUND THE PATTERN. THE RT SIDE OF THE COWLING WAS MODIFIED. THE FLT DEPARTED & AT AN ALT OF 500 FT, THE ACFT WAS OBSERVED IN AN UNCOORDINATED LT TURN. THE ACFT STALLED, DESCENDED LT WING LOW & CRASHED IN A FIELD. EXAM OF THE ACFT REVEALED NO FLT CONTROL MALFUNCTION. EXAM OF THE ENG REVEALED EVIDENCE OF A LEAN FUEL/AIR MIXTURE BUT THE REASON COULD NOT BE DETERMINED.

## Aircraft

- Registration: [N148DT](https://openairdocs.org/deregistered/N148DT-2013-03-25), registration cancelled 2013-03-25, S/N 0052LS (OpenAirDocs)
- Reported make and model: DANIEL S. TAYLOR SONERAI II LS (SONERAI II)
- Registry model: [Taylor Daniel S SONERAI II LS](https://openairdocs.org/model/taylor-daniel-s-sonerai-ii-ls) (registry code 056598B) (OpenAirDocs)
- Registry engine: [Volkswagen CONVERSION](https://openairdocs.org/engine/volkswagen-conversion) (registry code 63501, reciprocating) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 0052LS
- Engines: Volkswagen 2180CC reciprocating
- Damage: Destroyed
- Fire: On-Ground
- Flight: Part 91
- Operator: Olesen, James T.
- Registered owner: Bieber, S.A./Olesen J/Green,P
- Airworthiness certificate: Special, Experimental (Special)
- Airport: IA1, Autauga County, runway 9, 3,499 × 75 ft

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 20; flight instructor, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, valid medical--no waivers/lim.; seat: rear; toxicology performed; flight hours: 561 total, 21 in this make and model, 495 as pilot in command, 108 in the last 90 days, 25 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: 110° at 7 knots
- Visibility: 7 statute miles
- Lowest ceiling: 12,000 ft broken
- Temperature: 79 °F, dew point 61 °F
- Altimeter: 30.00 inHg
- Observed at: MGM, 10 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 19901021046479A](https://openairdocs.org/incident/19901021046479A), Oct 21, 1990: Amtrmo SONERAI2, Prattville, AL, Destroyed, 1 fatal. Engine quit in pattern. Homebuilt stalled and spun in. Had overheating cylinders and evidence mixture too lean.

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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