WPR11LA388

NTSB accident investigation · Air Tractor AT-602 · Pine Bluffs, WY · August 17, 2011

Accident · Minor injuriesLimited investigationFinal report
Date
August 17, 2011, 14:00 local (20:00 UTC)
Place
Pine Bluffs, WY
Injuries
1 minor
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N8518YAir Tractor AT-602
Defining event
Maneuvering-low-alt flying: Low altitude operation/event
Weather
Visual (VMC) · Day
Status
Completed · report December 27, 2011
Report
Approved by Office Director
NTSB office
Western Pacific Region
Parties
Federal Aviation Administration
FAA report
20110817016509A
Case key
81524

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

On this page

Probable cause

The pilot's failure to maintain clearance from power lines during an aerial application flight.

Findings · 3

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Performance/control parameters: altitudeAircraft › Aircraft oper/perf/capability · Not attained/maintainedAir Tractor AT-602: 11 casesAll aircraft: 1,310 casesProbable cause
Object/animal/substance: wireEnvironmental issues › Physical environment · Response/compensationAir Tractor AT-602: 10 casesAll aircraft: 588 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

According to the pilot, he was conducting an aerial application flight when he inadvertently struck power lines while maneuvering. The airplane struck the ground with the right wing first and then rolled to the left, coming to rest with the left wing and tail section contacting the ground. The pilot reported no mechanical problems with the airplane and stated the accident could have been prevented if he had paid more attention to the wire height, and maintained additional clearance above the wires.

Factual narrative

On August 17, 2011, about 1400 mountain daylight time, an Air Tractor, Inc., AT-602, N8518Y, impacted power line wires while maneuvering to spray a potato field near Pine Bluffs, Wyoming. The impact with the wires directed the airplane toward the ground and resulted in an unplanned landing. Top Hat Aerial Applicators, Inc., operated the aerial application flight under the provisions of 14 Code of Federal Regulations Part 137. The pilot, the sole occupant, received minor injuries; the airplane was substantially damaged. Visual meteorological conditions prevailed for the local area flight, and no flight plan had been filed. The flight departed from Pine Bluffs Municipal Airport (82V), Pine Bluffs, Wyoming, about 1300, and was scheduled to terminate at 82V. According to the pilot's written statement, the airplane struck the top wire of a power line set just prior to commencing the spraying operation. The pilot stated that the airplane descended toward the field, and the right wing hit the ground followed by the engine. The airplane rolled to the left, with the left wing and tail sections contacting the ground; the airplane came to rest upright. The pilot reported no mechanical problems with the airplane, and the accident could have been prevented if he had paid more attention to the wire height and maintained additional clearance above the wires.

Aircraft

Registration
N8518Y
Reported as
Air Tractor AT-602
Category
Airplane
Serial number
602-0689
Engine
P&W PT6A SER, 750 horsepower, turbo prop
Damage
Substantial damage
Flight
Aerial application · Part 137
Airworthiness certificate
Special, Restricted (Special)
Departed
82V · Pine Bluffs, WY
Destination
82V · Pine Bluffs, WY
Airport
82V · Pine Bluffs Municipal Airport

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
47
Injuries
Minor
Certificate
Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 2, With waivers/limitations
Seat
Single
Flight hours
6,032 total · 3,000 in this make and model · 300 in the last 90 days · 170 in the last 30 days · 10 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
240° at 3 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
84 °F, dew point 50 °F
Altimeter
30.17 inHg
Observed at
IBM, 21 nm away

Docket · 1

The files NTSB released with the investigation on November 22, 2011, on NTSB’s docket system: statements, records, photos and specialists’ reports. 451 KB 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.