Aircraft Accident/Incident Report

Arlington, Arizona 85326
Wednesday, April 4, 2007 10:38 MST

NTSB Narrative Summary Released at Completion of Accident

The pilot departed the airport for a local personal flight in the amateur built experimental-category airplane. About 25 minutes after takeoff, the airplane was observed flying in an easterly direction at an undetermined altitude. The witness reported hearing the engine slow down and then speed up. Seconds later, the witness heard "what sounded like an explosion" followed by the airplane falling to the ground in multiple pieces. The witness was located approximately 1 mile from where the wreckage came to rest. Post accident examination of the wreckage revealed that the right wing's forward and aft solid flying wires, turnbuckles and respective wire anchor attachment brackets remained intact, however the attachment brackets were separated from the forward and aft spar assemblies. The four through bolts (AN3 3/16-inch-diameter) associated with the forward brackets were fractured along the bolt shank near the bolt head. The bolts were necked down and were bent near the fracture points; the fracture surfaces were angular. Only two of the four through bolts associated with the aft bracket were recovered and similar findings were noted; the bolts were necked down and the fracture surfaces were angular. The builder's instruction manual for the airplane recommends AN3 (3/16-inch-diameter) anchor attach bracket bolts for standard operations and AN4 (1/4-inch-diameter) anchor attach bracket bolts if aerobatics are intended to be performed in the airplane. The specified anchor attachment bracket bolts (both AN3 and AN4) range in length from 5-1/2-inches to 6-3/4-inches. A personal friend of the pilot reported that about 2 weeks before the accident, the pilot completed a flight in the accident airplane. Upon returning from the flight, the pilot stated that he had completed a "slow roll." The pilot stated the airplane performed well during the flight.

NTSB Probable Cause Narrative

The pilot exceeding the design stress limits of the aircraft while maneuvering in intentional aerobatics.

Event Information

Type of Event Accident
Event Date 4/4/2007
Event Day of the Week Wednesday
Time of Event 1038
Event Time Zone Mountain Standard Time
Event City Arlington
Event State ARIZONA
Event Country --
Zipcode of the event site 85326
Event Date Year 2007
Event Date Month 4
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 331867N
Event Location Longitude 1124502W
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 1051 Mountain Daylight Time
Direction of event from weather observation facility (degrees) 90
Weather Observation Facility ID KPHX
Elevation of weather observation facility 1135
Distance of event from weather observation facility (units?) 32
Time Zone of the weather observation MDT
Lighting Conditions Day
Lowest Ceiling Height 25000
Lowest Non-Ceiling Height 20000
Sky/Lowest/Cloud Conditions Few
Sky Condition for Lowest Ceiling Broken
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 28
Dew Point at event time (in degress fahrenheit) -2
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) 30.04
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury Fatal
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal 1
Injury Total Minor --
Injury Total None --
Injury Total Serious --
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 23425
NTSB Notification Source FAA-ROC
NTSB Notification Date Apr 4 2007 12:00AM
NTSB Notification Time --
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Apr 30 2008 1:28PM
User who most recently changed record NTSB\johb
Basic weather conditions Visual Meteorological Cond
FAA District Office Scottsdale, Arizona

Aircraft Involved

Aircraft #1

Aircraft Registration Number N101LX
NTSB Number SEA07LA090
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Burton
Aircraft Model Fly Baby
Aircraft Series Identifier --
Aircraft Serial Number LBX101
Certified Max Gross Weight --
Aircraft Category Airplane
Aircraft Registration Class --
Aircraft is a homebuilt? Yes
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 Unknown
Date of Last Inspection --
Airframe hours since last inspection --
Airframe Hours --
ELT Installed No
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name Paul W. Kingsland
Aircraft Owner Street Address --
Aircraft Owner City Phoenix
Aircraft Owner State AZ
Aircraft Owner Country USA
Aircraft Owner Zipcode 85032
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) Personal
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code BXK
Departure City BUCKEYE
Departure State AZ
Departure Country USA
Departure Time 1013
Departure Time Zone MST
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
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Apr 8 2008 3:38PM
User who most recently changed record STAM
Since inspection or accident --
Event Location Runway Number and Location NA
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --