# NTSB LAX84LA342: Lee Thorpe T-18, N147DS, Lee Vining, CA, June 9, 1984

- Type: NTSB accident investigation
- Classification: Accident · Serious injuries · Limited investigation · Final report
- Date: June 9, 1984, 09:00 local (16:00 UTC)
- Place: Lee Vining, CA
- Coordinates: 37.990982, -119.110076 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=37.9910&lon=-119.1101&mi=10
- Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping)
- Highest injury: Serious injuries
- Injuries: 1 serious, 1 minor
- Status: Completed
- Report: Approved by Office Director
- NTSB case key (mKey): 24304
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=LAX84LA342
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/24304/pdf
- Page: https://openairdocs.org/ntsb/LAX84LA342

## Sequence of events

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

- Loss of control - on ground/water, landing - roll
  - weather condition - high density altitude
  - brakes(normal) - improper use of, pilot in command (cause)
  - rudder - improper use of, pilot in command (cause)
  - directional control - not maintained, pilot in command (cause)
  - ground loop/swerve - inadvertent, pilot in command
- Nose over, landing - roll
  - terrain condition - rough/uneven (contributing factor)

## Analysis

THE PLT REPORTED THAT DURING A LANDING IN CALM AIR, THE ACFT BEGAN VEERING RIGHT WHEN HE APPLIED THE BRAKES. HE CORRECTED WITH LEFT RUDDER & BRAKE, THEN THE ACFT VEERED LEFT. SUBSEQUENTLY, IT VEERED OFF THE LEFT SIDE OF THE RWY, WENT DOWN A GRADE & NOSED OVER. THE PLT REPORTED THAT THERE WAS NOTHING WRONG WITH HIS ACFT & SUGGESTED THAT HE OVER-CORRECTED WHEN HE APPLIED LEFT RUDDER & BRAKE. THE ARPT ELEV WAS 6802 FT.

## Aircraft

- Registration: [N147DS](https://openairdocs.org/aircraft/N147DS), registered now, S/N 439, built 1973 (OpenAirDocs)
- Reported make and model: LEE THORPE T-18 (THORPE T-1)
- Registry model: [Lee THORPE T-18](https://openairdocs.org/model/lee-thorpe-t-18) (registry code 8951026) (OpenAirDocs)
- Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs)
- Category: Airplane, amateur-built
- Serial number: 439
- Airframe hours: 590
- Engines: LYCOMING O-320 150 horsepower reciprocating
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: Delta Sierra Services
- Airworthiness certificate: Special, Experimental (Special)
- Departed: APC, NAPA, CA
- Destination: O24, LEE VINING, CA
- Flight plan: VFR
- Airport: 024, Lee Vining, runway 14, 4,090 × 50 ft, asphalt

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 66; commercial; airplane ratings: single-engine land, single-engine sea; medical: class 3, valid medical--w/ waivers/lim; seat: left; flight hours: 1,950 total, 170 in this make and model, 30 in the last 90 days, 12 in the last 30 days

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 40 statute miles
- Lowest ceiling: none
- Temperature: 72 °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 19840609023239A](https://openairdocs.org/incident/19840609023239A), Jun 9, 1984: Amtrth THORPT18, Lee Vining, CA, Substantial damage. Lost directional control on the landing roll. Ran down an embankment and nosed over. Pilot blamed his large feet.

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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