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Aviation safety reports, made easier to study

NTSB Reports is an independent research and search tool for public aviation accident and incident records. It brings NTSB aviation reports, structured fields, docket files, extracted figures, photos, videos, and update history into one searchable interface.

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February 23, 1995 · Ayres S2R-T34AG · N4021Z

Moses Lake, WA

Overview

Report Status
Final with probable cause
Event Type
Accident
Date
February 23, 1995
Injury Outcomes
1 injury (1 serious injury)
Location
Moses Lake, WA
Aircraft
Ayres S2R-T34AG
Tail Number
N4021Z
Operator
Moses Lake Air Service
Injuries
Serious
Aircraft Damage
Substantial
NTSB Number
SEA95LA055

THE PILOT STATED THAT, WHILE RETURNING TO BASE TO RELOAD AFTER CONDUCTING AERIAL APPLICATION ACTIVITY, HIS ATTENTION WAS DIVERTED OUT THE LEFT WINDOW BY ANOTHER FIELD WHICH WAS TO BE SPRAYED LATER. WHEN HE LOOKED AHEAD AGAIN, HE SAW POWER TRANSMISSION LINES IMMEDIATELY AHEAD AND APPLIED IMMEDIATE, ABRUPT FORWARD PRESSURE ON THE STICK. THE AIRCRAFT MISSED THE POWER LINES BUT COLLIDED WITH TERRAIN.

NTSB Probable Cause

THE PILOT-IN-COMMAND'S FAILURE TO MAINTAIN ADEQUATE ALTITUDE ABOVE THE TERRAIN. FACTORS INCLUDE HIS DIVERTED ATTENTION AND ATTEMPTED MANEUVER TO AVOID OBSTRUCTIONS.

Full Narrative

On February 23 1995, approximately 1420 Pacific standard time (PST), an Ayres S2R-T34AG, N4021Z, impacted the terrain while maneuvering to avoid power lines near Moses Lake, Washington. The commercial pilot, who was the sole occupant of the aircraft, received serious injuries, and the aircraft sustained substantial damage. The FAR Part 137 aerial application flight, which had departed the operator's airstrip about 30 minutes earlier, was being operated in visual meteorological conditions. No flight plan had been filed, and there was no fire. The pilot was returning to the airstrip to reload when his attention was distracted by a field which was to be sprayed later. When his attention returned to his flying, he spotted power transmission lines immediately in front of him. He quickly dove the aircraft in order to avoid the wires, but collided with an earthen berm as he passed underneath.

Flight

Event TypeAccident
Event Time14:20 PST
Nearest Airport0nm
Runway0
Flight Plan FiledNone
Aircraft FireNo
Aircraft ExplosionNo

Aircraft

AircraftAyres S2R-T34AG
Tail NumberN4021Z
Aircraft CategoryAir
DamageSubstantial
OperatorMoses Lake Air Service
Operating RulePart 137
Engines1
Engine TypeTurboprop
Engine DetailsP&W · PT6-34AG · Turboprop · 750
Seats1

People & Injuries

Injury Summary1 injury (1 serious injury)
Fatal0
Serious1
Minor0
Uninjured0
Total1
Crew 1Age 40 · Second Class

Conditions

ConditionsVMC
LightDaylight
WindCalm
Visibility20 sm
CeilingNone
Temperature / Dew Point61 F / 0 C
Altimeter0
Weather SourcePILO

Appendix: Source Data