Aircraft Accident/Incident Report

Cleveland, Oklahoma 74020
Thursday, December 21, 1995 14:42 CST

NTSB Narrative Summary Released at Completion of Accident

At 1350 cst, a McAlester FSS specialist gave a preflight briefing to a Cessna 421 pilot concerning IMC (instrument meteorological conditions) along the route & advised that VFR flight was not recommended. Cloud tops were at 12,000', & freezing level was at 1,600'. A PIREP at 1416 cst reported light mixed icing from 6,400' to 9,000' at Oklahoma City. At 1424 cst, the pilot departed Tulsa (VFR), then radar service was terminated. No further communication was received from the airplane. Radar data showed that it climbed westerly, reaching 9,800' at 1440 cst; during the next 88 seconds, its heading & altitude deviated until it descended through 3,200'. Ground witnesses saw the airplane descend out of low clouds in a 'flat spin' & crash. No preimpact mechanical failure was found. The airplane's gross weight was about 150 lbs over its maximum limit. In November 1995, the pilot received 10 hrs of Cessna 421 simulator training; his instructor noted in training records that he met minimum standards for VFR, but 'under IMC conditions,' he 'could not maintain altitude within 1,300 feet or heading within 40 degrees.' Postmortem toxicology tests showed 0.079 mcg/ml Nordiazepam (metabolite of Valium) in kidney fluid, 0.044 mcg/ml Desipramine (metabolite of Imipramine, an antidepressant) in spleen fluid, 0.733 mcg/ml Diphenhydramine (Benadryl) in spleen fluid, & 0.353 mcg/ml Diphenhydramine in lung fluid. These medications are not approved by the FAA for use while flying. The airplane was equipped for flight in icing & IFR conditions.

NTSB Probable Cause Narrative

the pilot's continued VFR flight into instrument meteorological conditions (IMC), and his failure to maintain control of the airplane after encountering adverse weather conditions, which resulted in a stall/spin. Factors relating to the accident were: pilot impairment due to a medication that was not approved by the FAA for use while flying, the adverse weather conditions, and the pilot's lack of instrument proficiency in the Cessna 421 airplane.

Event Information

Type of Event Accident
Event Date 12/21/1995
Event Day of the Week Thursday
Time of Event 1442
Event Time Zone Central Standard Time
Event City CLEVELAND
Event State OKLAHOMA
Event Country --
Zipcode of the event site 74020
Event Date Year 1995
Event Date Month 12
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 Witness
Time of the weather observation 0
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID
Elevation of weather observation facility 0
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation
Lighting Conditions Day
Lowest Ceiling Height 500
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Unknown
Sky Condition for Lowest Ceiling Overcast
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 5
Air Temperature at event time (in degrees celsius) --
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Unknown
Wind Gust Indicator Unknown
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) --
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 6
Injury Total Minor --
Injury Total None --
Injury Total Serious --
Injury Total All 6
Investigating Agency NTSB
NTSB Docket Number (internal use) 1988
NTSB Notification Source --
NTSB Notification Date Dec 21 1995 12:00AM
NTSB Notification Time 1600
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 7 2000 4:51PM
User who most recently changed record dbo
Basic weather conditions Instrument Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N421EP
NTSB Number FTW96FA073
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Destroyed
Aircraft Fire Ground
Aircraft Explosion None
Aircraft Manufacturer's Full Name Cessna
Aircraft Model 421C
Aircraft Series Identifier 421C
Aircraft Serial Number 421C-1236
Certified Max Gross Weight 7610
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 8
Number of Engines 2
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Jul 7 1995 12:00AM
Airframe hours since last inspection --
Airframe Hours --
ELT Installed Yes
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name INSURED TITLES OF TUSCALOOSA
Aircraft Owner Street Address 2301 UNIVERSITY BLVD.
Aircraft Owner City TUSCALOOSA
Aircraft Owner State AL
Aircraft Owner Country
Aircraft Owner Zipcode 35401
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 TUL
Departure City TULSA
Departure State OK
Departure Country
Departure Time 1424
Departure Time Zone CST
Destination Same as Local Flt --
Destination Airport Code ASE
Destination City ASPEN
Destination State CO
Destination Country
Specific Phase of Flight Descent - uncontrolled
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 --