Aircraft Accident/Incident Report

Garden Banks
Monday, August 26, 1991 7:15 CDT

NTSB Narrative Summary Released at Completion of Accident

THE HELICOPTER WAS ON FINAL APCH TO AN OIL RIG IN THE GULF OF MEXICO, WHEN TAIL ROTOR AUTHORITY & DRCTNL CTL WERE LOST. AS THE CREW BEGAN AN AUTOROTATION TO THE WATER, THE HELICOPTER SPUN OUT OF CTL TO THE RGT. IT MADE 2 TO 3 REVOLUTIONS & IMPACTED THE WATER. THE RGT FLOATATION GEAR DEPLOYED, BUT THE LEFT FLOATATION GEAR DIDN'T DEPLOY, BECAUSE THE PNEUMATIC LINES WERE PULLED APART DRG IMPACT. SUBSEQUENLTY, THE HELICOPTER ROLLED OVER DRG TOUCHDOWN IN THE WATER. THE CREW & 10 OF 11 PSGRS ESCAPED THRU THE EMERG WINDOWS. THE OTR PSGR REMAINED IN HIS SEAT (INCAPACITATED FM INJURIES) & DROWNED. AN INVESTIGATION REVEALED THE #1 HANGER BEARING HAD OVERHEATED & DISINTEGRATED AT AN EXTREMELY HIGH TEMPERATURE. SUBSEQUENTLY, THE TAIL ROTOR DRIVE SHAFT FAILED.

NTSB Probable Cause Narrative

OVERHEATING AND SUBSEQUENT FAILURE OF THE NUMBER ONE TAIL ROTOR HANGER BEARING FOR AN UNDETERINED REASON, AND FAILURE OF THE TAIL ROTOR DRIVE SHAFT.

Event Information

Type of Event Accident
Event Date 8/26/1991
Event Day of the Week Monday
Time of Event 715
Event Time Zone Central Daylight Time
Event City GARDEN BANKS
Event State GULF OF MEXICO
Event Country --
Zipcode of the event site 00000
Event Date Year 1991
Event Date Month 8
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 0
Degrees magnetic from airport 0
Airport Elevation --
Weather Briefing Completeness Not pertinent
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 5000
Lowest Non-Ceiling Height 1200
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling Broken
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) --
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 70
Variable Wind Indicator Unknown
Wind Speed (knots) 3
Wind Velocity Indicator Unknown
Wind Gust Indicator Unknown
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 Fatal
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal 1
Injury Total Minor 1
Injury Total None 7
Injury Total Serious 4
Injury Total All 6
Investigating Agency NTSB
NTSB Docket Number (internal use) 1898
NTSB Notification Source --
NTSB Notification Date --
NTSB Notification Time 0
Fiche Number and/or location -used to find docket information 45837
Date of most recent change to record Dec 12 2000 10:39AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N3909F
NTSB Number FTW91FA155
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 Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name BELL
Aircraft Model 412
Aircraft Series Identifier 412
Aircraft Serial Number 33015
Certified Max Gross Weight 116600
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 13
Number of Engines 2
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Continuous Airworthiness
Date of Last Inspection Jun 13 1991 12:00AM
Airframe hours since last inspection 192
Airframe Hours 10337
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name ROBERT D. ARMSTONG
Aircraft Owner Street Address 909 POYDRAS - SUITE 2300
Aircraft Owner City NEW ORLEANS
Aircraft Owner State LA
Aircraft Owner Country
Aircraft Owner Zipcode 70112
Operator is an individual? --
Operator Name PETROLEUM HELICOPTERS
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address P.O. BOX 90808
Operator City LAFAYETTE
Operator State LA
Operator Country
Operator Zip code 70509
Operator Code PHM
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 Only
Type of Flying (Per_Bus / Primary) Unknown
Second Pilot on Board Yes
Departure Point Same as Event No
Departure Airport Code NONE
Departure City SHIP SHOLE 248
Departure State GM
Departure Country
Departure Time 650
Departure Time Zone CDT
Destination Same as Local Flt crash at destination city
Destination Airport Code
Destination City
Destination State
Destination Country
Specific Phase of Flight Landing
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:30AM
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 --