Aircraft Accident/Incident Report

Grand Canyon, Arizona 86023
Friday, August 2, 1996 10:08 MST

NTSB Narrative Summary Released at Completion of Accident

The pilot was deviating for weather and reported cumulous buildups and electrical discharges with tops at and above his flight level. Radar data showed the aircraft ground track turning north as it began an unannounced descent. The descent continued until radar contact was lost. Witnesses reported seeing the aircraft break out of the overcast, making a series of random turns, climbs, and dives before it collided with the canyon wall. The aircraft collided with the canyon wall near Pima Point. Thunderstorms had developed along the route several hours sooner than forecast. Examination of recorded weather radar data disclosed that a level 6 thunderstorm with tops to 49,000 feet was present at the location and time of the accident. There was no record of the pilot requesting or receiving updated weather information after his final DUATS briefing 4 hours prior to the accident. No evidence of mechanical discrepancies were found during the wreckage examination.

NTSB Probable Cause Narrative

due to an in-flight loss of control resulting from a probable incapacitation for unknown reasons. The loss of control occurred while the aircraft was being flown in close proximity to a level 6 thunderstorm. The failure of the pilot to obtain current weather information was a factor in this accident.

Event Information

Type of Event Accident
Event Date 8/2/1996
Event Day of the Week Friday
Time of Event 1008
Event Time Zone Mountain Standard Time
Event City GRAND CANYON
Event State ARIZONA
Event Country --
Zipcode of the event site 86023
Event Date Year 1996
Event Date Month 8
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 Full
Investigator's weather source Weather Observation Facility
Time of the weather observation 954 Mountain Standard Time
Direction of event from weather observation facility (degrees) 342
Weather Observation Facility ID GCN
Elevation of weather observation facility 6606
Distance of event from weather observation facility (units?) 8
Time Zone of the weather observation MST
Lighting Conditions Day
Lowest Ceiling Height 4800
Lowest Non-Ceiling Height 3800
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling Broken
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) -6
Dew Point at event time (in degress fahrenheit) -11
Wind Direction (degrees magnetic) 140
Variable Wind Indicator Unknown
Wind Speed (knots) 11
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 30
Density Altitude (feet) --
Intensity of Precipitation Light
METAR weather report --
Event Highest Injury Fatal
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
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) 1830
NTSB Notification Source --
NTSB Notification Date Aug 2 1996 12:00AM
NTSB Notification Time 1042
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 8 2000 10:17AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N4634H
NTSB Number LAX96FA294
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed IFR
Flight plan Was Activated? --
Damage Destroyed
Aircraft Fire Ground
Aircraft Explosion None
Aircraft Manufacturer's Full Name Mooney
Aircraft Model M20K
Aircraft Series Identifier M20K
Aircraft Serial Number 25-0472
Certified Max Gross Weight 2981
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 4
Number of Engines 1
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Feb 8 1996 12:00AM
Airframe hours since last inspection --
Airframe Hours --
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name PAUL CAPEK
Aircraft Owner Street Address 3516 ELM AVENUE
Aircraft Owner City MANHATTAN BEACH
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 90266
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
Owner has at least one certificate None
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Unknown
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 TOA
Departure City TORRANCE
Departure State CA
Departure Country
Departure Time 744
Departure Time Zone PDT
Destination Same as Local Flt --
Destination Airport Code CBK
Destination City COLBY
Destination State KS
Destination Country
Specific Phase of Flight Cruise
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:34AM
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 --