Craig Field Airport
Aircraft Accident/Incident Report

Selma, Alabama 36701
Thursday, October 17, 1991 16:45 CDT

NTSB Narrative Summary Released at Completion of Accident

DURING CRUISE FLIGHT, THE ENGINE RPM DECREASED, MOMENTARILY. THE PILOT LANDED AND A MECHANIC CHECKED THE ENGINE. NO ANOMALIES WERE FOUND. A POST MAINTENANCE FLIGHT, IN THE LANDING PATTERN, WAS FLOWN TO VERIFY ENGINE OPERATION. ON FINAL APPROACH, THE ENGINE QUIT, AND THE AIRPLANE WAS LANDED IN ROUGH TERRAIN SHORT OF THE RUNWAY. EXAMINATION OF THE ENGINE REVEALED THAT THE NUMBER 2 CHECK COUNTERWEIGHT BLADE WAS FRACTURED. METALLURGICAL EXAMINATION DISCOVERED CORROSION PITTING ON THE INNER DIAMETER OF THE COUNTERWEIGHT PIN BUSHINGS, AS WELL AS EXCESSIVE INNER DIAMETER WEAR. THE COUNTERWEIGHT BLADE FRACTURE EXHIBITED EVIDENCE OF FATIGUE. A LOG BOOK ENTRY INDICATED THAT THE ENGINE HAD BEEN PREVIOUSLY DISASSEMBLED FOR EXAMINATION FOLLOWING A LIGHTNING STRIKE. THERE WAS NO RECORD OF AN ENGINE OVERHAUL. THE SAFETY BOARD BELIEVES THAT THE COUNTERWEIGHT FAILED IN FATIGUE, BECAUSE OF PREVIOUS PITTING DAMAGE TO THE BUSHINGS, FROM AN UNKNOWN SOURCE.

NTSB Probable Cause Narrative

THE FATIGUE FAILURE OF THE ENGINE CRANKSHAFT COUNTERWEIGHT BLADE, WHICH RESULTED FROM EXCESSIVE WEAR OF THE COUNTERWEIGHT PIN BUSHINGS, DUE TO CORROSION FROM AN UNKNOWN SOURCE.

Event Information

Type of Event Accident
Event Date 10/17/1991
Event Day of the Week Thursday
Time of Event 1645
Event Time Zone Central Daylight Time
Event City SELMA
Event State ALABAMA
Event Country --
Zipcode of the event site 36701
Event Date Year 1991
Event Date Month 10
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport CRAIG FIELD
Event Location Nearest Airport ID SEM
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles 0
Degrees magnetic from airport 320
Airport Elevation 166
Weather Briefing Completeness Unknown
Investigator's weather source Pilot
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 0
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
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) 24
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Calm
Wind Gust Indicator Unknown
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 30
Density Altitude (feet) 900
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury Minor
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
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) 1902
NTSB Notification Source --
NTSB Notification Date --
NTSB Notification Time 0
Fiche Number and/or location -used to find docket information 45841
Date of most recent change to record Dec 12 2000 10:47AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N3735Y
NTSB Number ATL92LA010
Missing Aircraft Indicator N
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 BEECH
Aircraft Model A36
Aircraft Series Identifier A36
Aircraft Serial Number E-1767
Certified Max Gross Weight 3600
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 6
Number of Engines 1
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Jul 17 1991 12:00AM
Airframe hours since last inspection 68
Airframe Hours 3070
ELT Installed Yes
ELT Activated Yes
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name GRAY, THOMAS L.
Aircraft Owner Street Address 2312 CALUMET AVENUE
Aircraft Owner City DECATUR
Aircraft Owner State AL
Aircraft Owner Country
Aircraft Owner Zipcode 36701
Operator is an individual? --
Operator Name GRAY, THOMAS L.
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address 2312 CALUMET AVENUE
Operator City DECATUR
Operator State AL
Operator Country
Operator Zip code 36701
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 Yes
Departure Airport Code
Departure City
Departure State
Departure Country
Departure Time 1630
Departure Time Zone EDT
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 Approach
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:35AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 14
Runway Length 8002
Runway Width 150
Sight Seeing flight No
Air Medical Flight No
Medical Flight --