# NTSB SEA90LA105: Air Tractor AT-401, N4530N, Jerome, ID, June 21, 1990

- Type: NTSB accident investigation
- Classification: Accident · No injuries · Limited investigation · Final report
- Date: June 21, 1990, 17:30 local (23:30 UTC)
- Place: Jerome, ID
- Coordinates: 42.730541, -114.430068 (estimated)
- Nearby events: https://openairdocs.org/map.md?lat=42.7305&lon=-114.4301&mi=10
- Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping)
- Highest injury: No injuries
- Injuries: 1 uninjured
- Status: Completed, report December 15, 1992
- Report: Approved by Office Director
- NTSB case key (mKey): 41214
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=SEA90LA105
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/41214/pdf
- Page: https://openairdocs.org/ntsb/SEA90LA105

## Probable cause

THE PILOT DID NOT MAINTAIN A PROPER ALTITUDE WHILE MANEUVERING TO REVERSE DIRECTION.

## Sequence of events

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

- In flight collision with terrain/water, maneuvering - turn to reverse direction
  - terrain condition - open field
  - proper altitude - not maintained, pilot in command (cause)

## Analysis

DURING AN AERIAL APPLICATION FLIGHT, THE PILOT HAD COMPLETED ONE PASS OVER THE FIELD AND A TURN TO REVERSE DIRECTION WAS MADE WITH PARTIAL FLAPS EXTENDED. THE PILOT RETRACTED THE FLAPS AT A LOW ALTITUDE AND THE AIRPLANE SETTLED. AS IT SETTLED, THE AIRPLANE COLLIDED INTO A DRAINAGE EMBANKMENT. THE PILOT REPORTED THAT THERE WERE NO MECHANICAL FAILURES OR MALFUNCTIONS WITH THE AIRPLANE AT THE TIME OF THE ACCIDENT.

## Aircraft

- Registration: [N4530N](https://openairdocs.org/deregistered/N4530N-2006-12-06), registration cancelled 2006-12-06, S/N 401-0762 (OpenAirDocs)
- Reported make and model: AIR TRACTOR AT-401
- Registry model: [Air Tractor AT-401](https://openairdocs.org/model/air-tractor-at-401) (registry code 0390204) (OpenAirDocs)
- Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs)
- Category: Airplane
- Serial number: 401-0762
- Engines: P&W R-1340-AN1 600 horsepower reciprocating
- Damage: Substantial damage
- Flight: Aerial application, Part 137
- Operator: William M. Walters
- Destination: U73

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 38; commercial, flight instructor; airplane ratings: single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, valid medical--no waivers/lim.; flight hours: 9,000 total, 35 in this make and model, 8,900 as pilot in command, 195 in the last 90 days, 75 in the last 30 days, 5 in the last 24 hours

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 50 statute miles
- Lowest ceiling: none
- Temperature: -0 °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 19900621029279A](https://openairdocs.org/incident/19900621029279A), Jun 21, 1990: Airtrc AT400A, Jerome, ID, Substantial damage. Let down over field to be sprayed after clearing trees. Raised flaps and settled into impact with a ditch.

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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