FTW02LA158

NTSB accident investigation · Air Tractor 402 · Hughes, AR · May 20, 2002

Accident · No injuriesLimited investigationFinal report
Date
May 20, 2002, 07:40 local (12:40 UTC)
Place
Hughes, AR
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N91660Air Tractor 402
Weather
Visual (VMC) · Day
Status
Completed · report April 1, 2003
Report
Approved by Office Director
Parties
Federal Aviation Administration
FAA report
20020520011209A
Case key
54751

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 pilot's failure to maintain directional control during the landing roll. Contributing factors were the malfunction of the tail wheel locking mechanism and the high vegetation along the sides of the airstrip.

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.

Hazardous materials leak/spillManeuvering - aerial application
Aerial application equipment - leak
Loss of control - on ground/waterLanding - roll
Directional control - not maintainedPilot in commandCause
Landing gear,gear locking mechanism - malfunctionFactor
On ground/water encounter with terrain/waterLanding - roll
Terrain condition - high vegetationFactor

Analysis

While conducting an aerial application flight, the pilot noticed that three spray nozzles were leaking. Several crops in the area were susceptible to the chemical being dispensed, prompting the pilot to divert and execute a landing at an alternate airstrip to fix the nozzles. After touching down, the pilot stated the tail wheel did not lock properly, which resulted in the airplane kicking to the left and departing the airstrip. The airplane's left spray boom then became entangled in the adjoining wheat, and the airplane ground looped. The pilot reported having trouble with the tail wheel locking mechanism about a week before the accident.

Factual narrative

On May 20, 2002, approximately 0740 central daylight time, an Air Tractor 402 agricultural airplane, N91660, sustained substantial damage while landing at a private grass airstrip near Hughes, Arkansas. The commercial pilot, sole occupant of the airplane, was not injured. The airplane was registered to and operated by Hutcherson Flying Service of Forrest City, Arkansas, under 14 Code of Federal Regulations Part 137. Visual meteorological conditions prevailed for the aerial application flight, and no flight plan was filed. The flight originated from another private airstrip near Blackfish, Arkansas, at 0720.

In the Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2), the pilot reported that while spraying a field, he was having trouble with three spray nozzles. There were numerous crops in the area that were susceptible to the chemical he was applying, prompting him to land at an alternate airstrip to repair the leaking nozzles. The pilot reported that after touching down, the "tail wheel locking mechanism failed" and he felt the airplane "kick to the left, like something had come loose back there." The airplane's left spray boom became entangled in the adjacent wheat crop, pulling it off the left side of the airstrip. The airplane ground looped, and came to rest in an upright position. The pilot stated that a week prior to the accident, he noticed problems with the tail wheel locking mechanism. The tail wheel bushings and fork were replaced, but "this didn't cure the problem."

An FAA inspector, who responded to the accident site, reported the left lower wing was damaged, the fuselage was twisted, and the rudder, elevator, and both horizontal and vertical stabilizers had sustained damage.

Aircraft

Registration
N91660
Reported as
Air Tractor 402
Category
Airplane
Serial number
402-0903
Airframe hours
4,636
Engine
Pratt & Whitney PT6-27, 650 horsepower, turbo prop
Damage
Substantial damage
Flight
Aerial application · Part 137
Registered owner
Hutcherson Flying Service
Airworthiness certificate
Special, Restricted (Special)
Last inspection
Annual · April 11, 2002 · 70 hours before
Departed
NONE · Hughes, AR

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
37
Injuries
None
Certificate
Commercial
Airplane ratings
Single-engine land
Medical
Class 2, Valid Medical--no waivers/lim.
Last flight review
April 29, 2001
Seat
Single
Flight hours
3,578 total · 150 in this make and model · 3,500 as pilot in command · 50 in the last 90 days · 50 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
Variable at 5 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
158 °F

Docket · 1

The files NTSB released with the investigation on December 10, 2002, on NTSB’s docket system: statements, records, photos and specialists’ reports. 804 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.

Other investigations on N91660 · 1

Matched to the same aircraft by N-number and date.