Aircraft Accident/Incident Report

Maryland Hts, Missouri 63043
Monday, February 27, 1995 8:15 CST

NTSB Narrative Summary Released at Completion of Accident

THE PILOT OF A TURBINE POWERED HELICOPTER SAID HE BEGAN A HOVER ABOUT THREE FEET ABOVE THE GROUND, TURNED THE HELICOPTER INTO THE WIND, AND INITIATED A TAKEOFF. ACCORDING TO WITNESSES, THE HELICOPTER HAD STARTED TO MOVE FORWARD AND HAD ATTAINED AN ALTITUDE OF ABOUT 25 FEET, WHEN THEY HEARD A CHANGE IN THE SOUND OF THE ENGINE. THE PILOT STATED 'AS POWER WAS BROUGHT IN, A LOUD METALLIC TYPE POP WAS HEARD.' HE SAID THE HELICOPTER YAWED LEFT AFTER THE 'POP' WAS HEARD, AND THAT IT DID NOT RESPOND TO CONTROL INPUTS. THE HELICOPTER FLEW OVER AN EMBANKMENT, AND ITS ROTOR BLADES STRUCK THE SIDE OF THE EMBANKMENT. AFTER THE BLADE STRIKE, THE HELICOPTER ROLLED OVER ONTO ITS LEFT SIDE, THEN ON ITS RIGHT SIDE AND CAME TO REST. EXAMINATION OF THE HELICOPTER AND ITS COMPONENTS REVEALED THE ATTACHMENT BOLTS THAT CONNECTED THE DRIVESHAFT TO THE GEARED PORTION OF THE DRIVESHAFT COUPLING HAD FAILED. METALLURGICAL EXAMINATION REVEALED THAT TWO OF THE BOLTS HAD FAILED FROM FATIGUE, THE OTHER TWO BOLTS HAD EVIDENCE OF OVERLOAD FAILURE. ALSO, AFTER DISASSEMBLY, A TENSION (CENTERING) SPRING WAS DISCOVERED TO BE MISSING FROM THE TRANSMISSION END OF THE DRIVESHAFT (WHICH WOULD HAVE ALLOWED THE BOLT HEADS TO CONTACT THE GREASE RETAINING PLATE). THE LAST ANNUAL INSPECTION OF THE HELICOPTER AND ENGINE WAS ON 11/3/93.

NTSB Probable Cause Narrative

FATIGUE FAILURE OF TWO ATTACHMENT BOLTS THAT CONNECTED THE DRIVESHAFT TO THE GEARED PORTION OF A DRIVESHAFT COUPLING. FACTORS RELATING TO THE ACCIDENT WERE: INADEQUATE MAINTENANCE, UNEVEN TERRAIN IN THE TOUCHDOWN AREA FOR THE FORCED LANDING, AND THE UNFAVORABLE HEIGHT/VELOCITY SITUATION OF THE HELICOPTER WHEN THE DRIVESHAFT DISCONNECT OCCURRED.

Event Information

Type of Event Accident
Event Date 2/27/1995
Event Day of the Week Monday
Time of Event 815
Event Time Zone Central Standard Time
Event City MARYLAND HTS
Event State MISSOURI
Event Country --
Zipcode of the event site 63043
Event Date Year 1995
Event Date Month 2
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 623
Weather Briefing Completeness Unknown
Investigator's weather source Weather Observation Facility
Time of the weather observation 850 Central Standard Time
Direction of event from weather observation facility (degrees) 60
Weather Observation Facility ID STL
Elevation of weather observation facility 603
Distance of event from weather observation facility (units?) 8
Time Zone of the weather observation CST
Lighting Conditions Day
Lowest Ceiling Height 2100
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Unknown
Sky Condition for Lowest Ceiling Broken
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) 10
Dew Point at event time (in degress fahrenheit) 9
Wind Direction (degrees magnetic) 110
Variable Wind Indicator Unknown
Wind Speed (knots) 4
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None 5
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 940
NTSB Notification Source --
NTSB Notification Date Feb 27 1995 12:00AM
NTSB Notification Time 1228
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 7 2000 4:02PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N970CC
NTSB Number CHI95LA093
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 BELL
Aircraft Model 206L
Aircraft Series Identifier 206L
Aircraft Serial Number 40534
Certified Max Gross Weight 4000
Aircraft Category Helicopter
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 7
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Nov 3 1993 12:00AM
Airframe hours since last inspection 74
Airframe Hours 5652
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name SLM CHARTERS, INC
Aircraft Owner Street Address 2316 BAYWARD BLVD
Aircraft Owner City WILMINGTON
Aircraft Owner State DE
Aircraft Owner Country
Aircraft Owner Zipcode 19802
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) Business
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code RLA
Departure City
Departure State
Departure Country
Departure Time 815
Departure Time Zone CST
Destination Same as Local Flt --
Destination Airport Code JEF
Destination City JEFFERSON
Destination State MO
Destination Country
Specific Phase of Flight Emergency landing
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 --