Ann Arbor Municipal Airport
Aircraft Accident/Incident Report

Ann Arbor, Michigan 48108
Saturday, September 9, 1995 12:17 CDT

NTSB Narrative Summary Released at Completion of Accident

While in cruise flight the helicopter sustained the loss of the entire tail rotor system. The helicopter landed successfully with no additional damage or any injuries. Examination revealed the loss was initiated by a fatigue crack in the skin of one of the tail rotor blades. The manufacturer determined that a manufacturing process used in making the blades initiated the fatigue failure due to a grinding process which removed material from the tail rotor skin.

NTSB Probable Cause Narrative

the manufacturer's inadequate quality control which led to a fatigue failure of the tail rotor blade.

Event Information

Type of Event Accident
Event Date 9/9/1995
Event Day of the Week Saturday
Time of Event 1217
Event Time Zone Central Daylight Time
Event City ANN ARBOR
Event State MICHIGAN
Event Country --
Zipcode of the event site 48108
Event Date Year 1995
Event Date Month 9
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport ANN ARBOR MUNICIPAL
Event Location Nearest Airport ID ARB
Indicates whether the acc/inc occurred off or on an airport On Airport
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation 839
Weather Briefing Completeness Unknown
Investigator's weather source Weather Observation Facility
Time of the weather observation 1045 Eastern Daylight Time
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID ARB
Elevation of weather observation facility 839
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation EDT
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) 20
Air Temperature at event time (in degrees celsius) --
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 350
Variable Wind Indicator Unknown
Wind Speed (knots) 8
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 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 3
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 1813
NTSB Notification Source --
NTSB Notification Date Sep 9 1995 12:00AM
NTSB Notification Time 1300
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 7 2000 4:35PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N232UM
NTSB Number CHI95FA320
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed Company VFR
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Bell
Aircraft Model 230
Aircraft Series Identifier 230
Aircraft Serial Number 23013
Certified Max Gross Weight 8400
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 6
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection AAIP
Date of Last Inspection Sep 5 1995 12:00AM
Airframe hours since last inspection 10
Airframe Hours 1188
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name FIRST SDCURITY BANK OF UTAH
Aircraft Owner Street Address 79 SOUTH MAIN ST.
Aircraft Owner City SALT LAKE CITY
Aircraft Owner State UT
Aircraft Owner Country USA
Aircraft Owner Zipcode 84111
Operator is an individual? No
Operator Name CORPORATE JETS, INC.
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address ALLEGHENY COUNTY AIRPORT
Operator City WEST MIFFLIN
Operator State PA
Operator Country USA
Operator Zip code 15122
Operator Code BAQA
Owner has at least one certificate Yes - certificate holder
Other Operator of large aircraft? No
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) Positioning
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code NONE
Departure City
Departure State MI
Departure Country
Departure Time 1212
Departure Time Zone EDT
Destination Same as Local Flt --
Destination Airport Code NONE
Destination City TOLEDO
Destination State OH
Destination Country
Specific Phase of Flight Cruise
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Feb 2 2009 2:43PM
User who most recently changed record johb
Since inspection or accident --
Event Location Runway Number and Location 24
Runway Length 3500
Runway Width 75
Sight Seeing flight No
Air Medical Flight Yes
Medical Flight --