Aircraft Accident/Incident Report

Bunnell, Florida 32110
Friday, August 25, 2006 13:08 EDT

NTSB Narrative Summary Released at Completion of Accident

The pilot had received an outlook briefing during the morning hours before the accident. The briefing included information regarding widely scattered thunderstorms and rain showers along portions of the pilot's planned route of flight. At the time of the accident, a convective weather significant to the safety of all aircraft (convective SIGMET) was in effect for the pilot's route of flight, and the information about the convective SIGMET was broadcast to the pilot by air traffic control (ATC). Several airplanes in the vicinity of the accident airplane were deviating around weather. Conversations between the accident pilot and the ATC controller were consistent with the accident airplane's weather radar functioning, and the possibility that the accident airplane's weather radar was providing more information than the ATC weather radar. Although the pilot initially declined a deviation query by ATC, he later accepted one. Shortly after, the pilot was unable to maintain his assigned altitude of 28,000 feet msl (FL 280), and the airplane impacted terrain consistent with a vertical descent. At the time of the accident, at FL 280, weak to moderate weather radar echoes existed. Very strong to intense weather radar echoes were seen about FL 200. The ATC facility was equipped with NEXRAD-derived weather displays. The weather displays had four settings: below FL 240, between FL 240 and FL 330, above FL 330, and from sea level to FL 600. At the time of the accident, the ATC controller's weather display indicated weak to moderate echoes above FL240. Very strong to intense weather radar echoes existed about FL200; however, the ATC controller did not have his weather display set to that altitude as he was not controlling traffic at that altitude. The investigation could not determine if the pilot was aware of the stronger intensity echoes below his altitude, or if the airplane's weather radar was depicting the stronger echoes. Examination of the wreckage did not reveal any preimpact mechanical malfunctions.

NTSB Probable Cause Narrative

The pilot's inadvertent encounter with thunderstorms.

Event Information

Type of Event Accident
Event Date 8/25/2006
Event Day of the Week Friday
Time of Event 1308
Event Time Zone Eastern Daylight Time
Event City Bunnell
Event State FLORIDA
Event Country --
Zipcode of the event site 32110
Event Date Year 2006
Event Date Month 8
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 291848N
Event Location Longitude 0811449W
Event Location Airport --
Event Location Nearest Airport ID NONE
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 1250 Eastern Daylight Time
Direction of event from weather observation facility (degrees) 90
Weather Observation Facility ID OMN
Elevation of weather observation facility 29
Distance of event from weather observation facility (units?) 8
Time Zone of the weather observation EDT
Lighting Conditions Day
Lowest Ceiling Height --
Lowest Non-Ceiling Height 2500
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 29
Dew Point at event time (in degress fahrenheit) 22
Wind Direction (degrees magnetic) 100
Variable Wind Indicator Wind direction could be determined
Wind Speed (knots) 9
Wind Velocity Indicator --
Wind Gust Indicator Gusting
Wind Gust (knots) 15
Altimeter Setting at event time (in. Hg) 29.89
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 2
Injury Total Minor --
Injury Total None --
Injury Total Serious --
Injury Total All 2
Investigating Agency NTSB
NTSB Docket Number (internal use) 22193
NTSB Notification Source SROC
NTSB Notification Date Aug 25 2006 12:00AM
NTSB Notification Time --
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Sep 27 2007 11:30AM
User who most recently changed record NTSB\johb
Basic weather conditions Visual Meteorological Cond
FAA District Office Orlando, FL

Aircraft Involved

Aircraft #1

Aircraft Registration Number N171MA
NTSB Number NYC06MA208
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed IFR
Flight plan Was Activated? Yes
Damage Destroyed
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Mitsubishi
Aircraft Model MU-2B-40
Aircraft Series Identifier --
Aircraft Serial Number 431 S.A.
Certified Max Gross Weight 10470
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 7
Number of Engines 2
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Continuous Airworthiness
Date of Last Inspection May 1 2006 12:00AM
Airframe hours since last inspection --
Airframe Hours 3802
ELT Installed Yes
ELT Activated Yes
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name Drug and Laboratory Disposal Inc.
Aircraft Owner Street Address --
Aircraft Owner City Plainwell
Aircraft Owner State MI
Aircraft Owner Country USA
Aircraft Owner Zipcode 49080
Operator is an individual? No
Operator Name Ward T. Walter
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address --
Operator City Plainwell
Operator State MI
Operator Country USA
Operator Zip code 49080
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 KBMG
Departure City Bloomington
Departure State IN
Departure Country USA
Departure Time 1030
Departure Time Zone EDT
Destination Same as Local Flt --
Destination Airport Code MYEM
Destination City Governors Harbo
Destination State --
Destination Country BF
Specific Phase of Flight Cruise
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Sep 5 2007 7:32PM
User who most recently changed record MUZD
Since inspection or accident Last Inspection
Event Location Runway Number and Location NA
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --