SEA97LA010

NTSB accident investigation · Piper PA-36-300 · Prosser, WA · October 10, 1996

Accident · FatalLimited investigationFinal report
Date
October 10, 1996, 08:45 local (15:45 UTC)
Place
Prosser, WA
Injuries
1 fatal
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N2331YPiper PA-36-300
Weather
Visual (VMC) · Day
Status
Completed · report June 30, 1997
Report
Approved by Office Director
FAA report
19961010031459A
Case key
42525

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

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Probable cause

The NTSB’s determination of the probable cause, and any contributing factors.

failure of the pilot to maintain clearance from the terrain, while en route to an apple orchard that he intended to spray. A factor relating to the accident was: the turbulent wind condition over the hills.

Analysis

The airplane departed for a second flight of the day to spray an apple orchard. The pilot had reported, that on the first flight, there was turbulence en route to the orchard, but the winds were calm at the orchard. During the second flight, the airplane impacted hills which were between the departure airport and the orchard. No preimpact malfunction or failure of the aircraft or engine was found.

Factual narrative

On October 10, 1996, about 0845 Pacific daylight time, a Piper PA-36-300, N2331Y, crashed in hills south of Prosser, Washington. The airplane was being operated under visual flight rules (VFR) as a local area aerial application flight when the accident occurred. The airplane, operated by Aircraft Applications Inc., sustained substantial damage. The certificated commercial pilot, the sole occupant, was fatally injured. Visual meteorological conditions prevailed.

The accident occurred on the second flight of the day. The first flight had departed the airport at 0730. After the first flight, the pilot reported that he had encountered a lot of turbulence between the departure runway and the hill where the accident eventually took place. However, he said that the wind was calm at the orchard site where the spraying was taking place, so 150 gallons of "Stop Drop", a hormone type product for control of preharvest drop of apples, was loaded onto the airplane. The pilot also added twenty gallons of fuel to give a total of 75 gallons of fuel on board.

The airplane departed the Prosser airport at 0835 in a westerly direction for several miles before turning south towards the hills which were between the airport and the orchard. Three witnesses who saw the airplane and heard the engine running, varied in their description of the engine noise from "popping" to "...running strong and all at once the sound stopped...".

FAA inspectors responded to the scene of the accident and documented the wreckage. A copy of this documentation is attached to this report. On October 25, 1996, an engine examination was accomplished at the Prosser airport under FAA supervision. No evidence of pre-impact failure was found. A copy of the engine examination is attached to this report.

An autopsy was performed on the pilot by Benton County. Cause of death was listed as "massive trauma to the head, neck and chest." Toxicological testing performed by the Civil Aero Medical Institute in Oklahoma City, Oklahoma resulted in negative findings for alcohol and drugs except for acetaminophen.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

In flight collision with terrain/waterCruise
Weather condition - turbulence,terrain inducedFactor
Clearance - not maintainedPilot in commandCause

Aircraft

Registration
N2331Y
Reported as
Piper PA-36-300
Category
Airplane
Serial number
36-8160004
Airframe hours
2,373
Engine
Lycoming IO-720-A1B, 400 horsepower, reciprocating
Damage
Substantial damage
Flight
Aerial application · Part 137
Registered owner
Marvin Bonny
Airworthiness certificate
Special, Restricted (Special)
Last inspection
Annual · April 1, 1996 · 144 hours before
Departed
S40 · WA

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
27
Certificates
Commercial, Flight instructor
Airplane ratings
Single-engine sea, Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--no waivers/lim.
Seat
Center
Toxicology
Performed
Flight hours
491 total · 28 in this make and model · 491 as pilot in command · 28 in the last 90 days · 12 in the last 30 days · 3 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
330° at 5 knots
Visibility
40 statute miles
Lowest ceiling
None
Temperature
61 °F, dew point 48 °F
Altimeter
29.00 inHg
Observed at
PSC, 31 nm away

Docket · 13

The files NTSB released with the investigation on August 22, 2025, on NTSB’s docket system: statements, records, photos and specialists’ reports. 2.2 MB in all.

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.