Aircraft Accident/Incident Report

W Cameron Blk
Sunday, May 7, 1989 14:04 CDT

NTSB Narrative Summary Released at Completion of Accident

THE TWIN ENGINE HELICOPTER WAS IN CRUISE FLIGHT OVER THE GULF OF MEXICO, WHEN IT SUDDENLY PITCHED NOSE DOWN AND DESCENDED UNCONTROLLED TO IMPACT INVERTED INTO THE WATER. IT SANK TO A DEPTH OF APPROXIMATELY 380 FEET. AFTER RECOVERY OF THE HELICOPTER, EXAMINATION REVEALED THAT AN INCORRECT HYDRAULIC SWITCH GUARD HELD THE TEST SWITCH IN THE RESET POSITION, ELECTRICALLY ISOLATING HYDRAULIC SYSTEM NUMBER TWO FROM OPERATION, AND THAT THE HYDRAULIC MODULE WAS IN THE NUMBER 1 SYSTEM. FURTHER INSPECTION AND TESTING FOUND A DEFECTIVE MICRO-SWITCH IN THE OUTBOARD LATERAL GUIDE ASSEMBLY OF THE HYDRAULIC MODULE. ADDITIONALLY, THE OPERATOR HAD NOT COMPLIED WITH A REQUIRED SERVICE BULLETIN FOR THE MODULE.

NTSB Probable Cause Narrative

THE PARTIAL ELECTRICAL FAILURE OF THE MICRO-SWITCH FOR THE OUTBOARD LATERAL GUIDE ASSEMBLY, AND THE INCORRECT GUARD INSTALLED ON THE HYDRAULIC TEST SWITCH, RESULTING IN A TOTAL HYDRAULIC FAILURE. FACTORS WERE: THE INCORRECT INSTALLATION OF THE GUARD BY AN UNKNOWN PERSON, THE FAILURE OF THE COMPANY TO COMPLY WITH THE SPECIFIED SERVICE BULLETIN.

Event Information

Type of Event Accident
Event Date 5/7/1989
Event Day of the Week Sunday
Time of Event 1404
Event Time Zone Central Daylight Time
Event City W CAMERON BLK
Event State GULF OF MEXICO
Event Country --
Zipcode of the event site 00000
Event Date Year 1989
Event Date Month 5
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport
Event Location Nearest Airport ID NONE
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 0
Airport Elevation --
Weather Briefing Completeness Unknown
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 0
Lowest Non-Ceiling Height 10000
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 25
Air Temperature at event time (in degrees celsius) 28
Dew Point at event time (in degress fahrenheit) 17
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) 0
Intensity of Precipitation Unknown
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) 2368
NTSB Notification Source --
NTSB Notification Date May 7 1989 12:00AM
NTSB Notification Time 2030
Fiche Number and/or location -used to find docket information 43008
Date of most recent change to record Dec 13 2000 12:40PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N2785B
NTSB Number FTW89FA093
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 135: Air Taxi & Commuter
Type of Flight Plan filed Company VFR
Flight plan Was Activated? --
Damage Destroyed
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name MBB
Aircraft Model BO-105S
Aircraft Series Identifier BO-105S
Aircraft Serial Number 636
Certified Max Gross Weight 5512
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 5
Number of Engines 2
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection AAIP
Date of Last Inspection May 6 1989 12:00AM
Airframe hours since last inspection 3
Airframe Hours 1781
ELT Installed Yes
ELT Activated Yes
ELT Aided Location of Event Site Yes
ELT Type --
Aircraft Owner Name MCDONNELL DOUGLAS FINANCE CORP
Aircraft Owner Street Address 340 GOLDEN SHORE
Aircraft Owner City LONG BEACH
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 90802
Operator is an individual? --
Operator Name AIR LOGISTICS
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address 3921 INDUSTRIAL DR.
Operator City NEW IBERIA
Operator State LA
Operator Country
Operator Zip code 70560
Operator Code SW-N
Owner has at least one certificate Yes - certificate holder
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 Non-scheduled
Indicates Domestic or International Flight Domestic
Operator carrying Pax/Cargo/Mail Passenger/Cargo
Type of Flying (Per_Bus / Primary) Unknown
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code NONE
Departure City HI-A330
Departure State GM
Departure Country
Departure Time 1401
Departure Time Zone CDT
Destination Same as Local Flt --
Destination Airport Code NONE
Destination City WC-643
Destination State GM
Destination Country
Specific Phase of Flight Cruise
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 0
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --