Aircraft Accident/Incident Report

Downs, Kansas 67437
Wednesday, April 20, 2005 18:15 CDT

NTSB Narrative Summary Released at Completion of Accident

The agricultural spray airplane sustained substantial damage during a forced landing to a farm field after a loss of engine power. The pilot reported that he was "pulling the airplane up into a right hand turn" at the end of a spray run when he heard a loud "bang" and the engine started to run "really rough." He executed a forced landing to a field. The landing gear broke off due to the soft field conditions. The engine was a 450 horsepower Pratt & Whitney R-985-14B engine. The engine was overhauled 43 hours prior to the accident. At overhaul, the engine had accumulated a total time of 7,027.1 hours. The engine logbook noted that AD 78-0807 was complied with. AD 78-0807 was effective May 2, 1978 for ultrasonic and visual inspections every 150 hours time in service to detect cracking and "to prevent cylinder head separation from the barrel." The logbook did not contain specific information on the previous histories of the installed cylinders. The inspection of the airplane revealed that the number 2 cylinder was broken at the third large cooling vent up from the bottom. The upper portion on the head assembly had separated from the sleeve. The National Transportation Safety Board's (NTSB) Materials Laboratory report noted that the fracture faces were covered by extensive and heavy combustion products and required extensive cleanings to reveal fracture details. Examinations of the fracture faces revealed features and topography indicative of a large area of fatigue progression. The fatigue area was on the aft side of the cylinder, biased toward the exhaust valve. Fracture face markings indicative of multiple fatigue initiation at the inner diameter threads along a wide arc of approximately 140 degrees. Progression was radial through the head with complete penetration over and arc of about 60 degrees centered in the fatigue region. The cylinder head was permanently marked with UT05, UT97, UT91, UT89, and UT89 stamped in the head near the intake port. The "UT" markings on the head are consistent with the markings required by AD 78-0807 and they denote five different ultrasonic inspections since 1989.

NTSB Probable Cause Narrative

The loss of engine power due to the failure of the number two cylinder which was the result of the maintenance facility's failure to detect the fatigue crack in the number two cylinder during the engine overhaul. A factor to the accident was the soft field.

Event Information

Type of Event Accident
Event Date 4/20/2005
Event Day of the Week Wednesday
Time of Event 1815
Event Time Zone Central Daylight Time
Event City Downs
Event State KANSAS
Event Country --
Zipcode of the event site 67437
Event Date Year 2005
Event Date Month 4
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 395033N
Event Location Longitude 0985467W
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 --
Investigator's weather source Weather Observation Facility
Time of the weather observation 1853 Central Daylight Time
Direction of event from weather observation facility (degrees) 195
Weather Observation Facility ID RSL
Elevation of weather observation facility 1862
Distance of event from weather observation facility (units?) 40
Time Zone of the weather observation CDT
Lighting Conditions --
Lowest Ceiling Height --
Lowest Non-Ceiling Height --
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling --
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 27
Dew Point at event time (in degress fahrenheit) 17
Wind Direction (degrees magnetic) 160
Variable Wind Indicator Wind direction could be determined
Wind Speed (knots) 4
Wind Velocity Indicator --
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 29.74
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury Minor
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
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) 19314
NTSB Notification Source FAA
NTSB Notification Date Apr 20 2005 12:00AM
NTSB Notification Time 2104
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Mar 28 2006 1:55PM
User who most recently changed record NTSB\JOHB
Basic weather conditions Visual Meteorological Cond
FAA District Office FAA-Wichita, KS FSDO

Aircraft Involved

Aircraft #1

Aircraft Registration Number N9026F
NTSB Number CHI05LA104
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 137: Agricultural
Type of Flight Plan filed None
Flight plan Was Activated? No
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Weatherly
Aircraft Model 620B
Aircraft Series Identifier --
Aircraft Serial Number 1639
Certified Max Gross Weight --
Aircraft Category Airplane
Aircraft Registration Class --
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 Mar 1 2005 12:00AM
Airframe hours since last inspection 43
Airframe Hours 2319
ELT Installed No
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name AG Care By Air Inc.
Aircraft Owner Street Address P.O. Box 192
Aircraft Owner City Smith Center
Aircraft Owner State KS
Aircraft Owner Country USA
Aircraft Owner Zipcode 66967
Operator is an individual? No
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 --
Owner has at least one certificate None
Other Operator of large aircraft? --
Certified for Part 133 or 137 Operation --
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Aerial Application
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code --
Departure City Private
Departure State --
Departure Country --
Departure Time 1730
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 Maneuvering - aerial application
Report sent to ICAO? No
Evacuation occurred No
Date of most recent change to record Jan 5 2006 2:34PM
User who most recently changed record SULP
Since inspection or accident Time of Accident
Event Location Runway Number and Location NA
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --