Aircraft Accident/Incident Report

Bay City, Texas 77414
Thursday, October 7, 1999 16:20 CDT

NTSB Narrative Summary Released at Completion of Accident

The pilot completed the 8th seeding pass over a field and was turning to make the 9th pass when the agricultural airplane shuddered and made three uncommanded banks prior to impacting the terrain. The pilot initially stated that he flew through his own wake turbulence and stalled the airplane while in a 60-degree bank to the right. However, the pilot later stated that he thought the propeller may have malfunctioned resulting in the loss of airplane control. Post-accident examination of the airplane flight controls and the propeller revealed no anomalies that would have prevented normal operation of the aircraft prior to the accident.

NTSB Probable Cause Narrative

The pilot's inadvertent stall. A factor was the pilot's encounter with the airplane's wake turbulence.

Event Information

Type of Event Accident
Event Date 10/7/1999
Event Day of the Week Thursday
Time of Event 1620
Event Time Zone Central Daylight Time
Event City BAY CITY
Event State TEXAS
Event Country --
Zipcode of the event site 77414
Event Date Year 1999
Event Date Month 10
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude --
Event Location Longitude --
Event Location Airport
Event Location Nearest Airport ID
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness Unknown
Investigator's weather source Weather Observation Facility
Time of the weather observation 1652 Central Daylight Time
Direction of event from weather observation facility (degrees) 220
Weather Observation Facility ID PSX
Elevation of weather observation facility 15
Distance of event from weather observation facility (units?) 25
Time Zone of the weather observation CDT
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 25000
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 7
Air Temperature at event time (in degrees celsius) 27
Dew Point at event time (in degress fahrenheit) 17
Wind Direction (degrees magnetic) 150
Variable Wind Indicator Unknown
Wind Speed (knots) 9
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury Minor
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor 1
Injury Total None --
Injury Total Serious --
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 1948
NTSB Notification Source --
NTSB Notification Date Oct 8 1999 12:00AM
NTSB Notification Time 730
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Jun 3 2001 4:45AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N61768
NTSB Number FTW00LA008
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 137: Agricultural
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Air Tractor
Aircraft Model AT-502B
Aircraft Series Identifier AT-502B
Aircraft Serial Number 502B-0387
Certified Max Gross Weight 9400
Aircraft Category Airplane
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 1
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Apr 14 1999 12:00AM
Airframe hours since last inspection 396
Airframe Hours 1425
ELT Installed No
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name AVIATION SERVICES UNLIMITED
Aircraft Owner Street Address 1901 SIMS AVENUE
Aircraft Owner City BAY CITY
Aircraft Owner State TX
Aircraft Owner Country
Aircraft Owner Zipcode 77414
Operator is an individual? --
Operator Name
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address
Operator City
Operator State
Operator Country
Operator Zip code
Operator Code XU9G
Owner has at least one certificate Yes - certificate holder
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Agriculture
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not Unknown
Indicates Domestic or International Flight Unknown
Operator carrying Pax/Cargo/Mail Unknown
Type of Flying (Per_Bus / Primary) Aerial Application
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code 3R1
Departure City
Departure State
Departure Country
Departure Time 1606
Departure Time Zone CDT
Destination Same as Local Flt dest & departure same, accident can occur anywhere
Destination Airport Code
Destination City
Destination State
Destination Country
Specific Phase of Flight --
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jun 3 2001 4:08AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --