# NTSB FTW91LA068: Piper PA-18-150, N4695Y, Port Lavaca, TX, April 17, 1991

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: April 17, 1991, 14:50 local (19:50 UTC)
- Place: Port Lavaca, TX
- Coordinates: 28.609882, -96.620651 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=28.6099&lon=-96.6207&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 2 serious
- Status: Completed, report March 31, 1993
- Report: Approved by Office Director
- NTSB case key (mKey): 23326
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=FTW91LA068
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/23326/pdf
- Page: https://openairdocs.org/ntsb/FTW91LA068

## Probable cause

THE PILOT'S INADVERTENT STALL AT AN ALTITUDE TOO LOW FOR RECOVERY. A FACTOR WAS THE PILOT'S LOW PASS.

## Sequence of events

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

- In flight collision with terrain/water, maneuvering
  - low pass - performed, pilot in command (contributing factor)
  - altitude - inadequate, pilot in command
  - stall - inadvertent, pilot in command (cause)

## Analysis

THE AIRPLANE EXECUTED A STEEP LEFT TURN, STALLED, AND DESCENDED NOSE LOW INTO A TREE AND THE GROUND WHILE SEARCHING FOR A PIPE LEAK IN AN OIL FIELD. INSPECTION OF THE WRECKAGE REVEALED ADEQAUTE FUEL, CONTINUITY AND NO MECHANICAL MALFUNCTION. ENGINE DISASSEMBLY FAILED TO UNCOVER ANY DISCREPANCY. A WITNESS OBSERVED THE AIRPLANE FLYING LOW TO THE GROUND AND SLOWED DOWN TO WATCH. THE WITNESS SAW THE AIRPLANE CIRCLE AND GO DOWN.

## Aircraft

- Registration: [N4695Y](https://openairdocs.org/aircraft/N4695Y), registered now, S/N 18-7309019, built 1973 (OpenAirDocs)
- Reported make and model: PIPER PA-18-150
- Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 18-7309019
- Engines: LYCOMING O-320-A2B 150 horsepower reciprocating
- Damage: Destroyed
- Flight: Business, Part 91
- Operator: Abner M. Ussery
- Registered owner: Abner M. Ussery
- Departed: NONE, EL MATON, TX
- Destination: NONE

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 33; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; flight hours: 401 total, 337 in this make and model, 401 as pilot in command, 31 in the last 90 days, 13 in the last 30 days, 1 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: 180° at 5 knots
- Visibility: 10 statute miles
- Lowest ceiling: 2,000 ft overcast
- Temperature: 75 °F, dew point -0 °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 19910417011369A](https://openairdocs.org/incident/19910417011369A), Apr 17, 1991: Piper PA18150, Port Lavaca, TX, Destroyed. Stalled in a steep low altitude turn while searching for an oil pipeline leak.

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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