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NTSB Report
August 8, 1991 · Bell 412 · N177EH
Rowan Midland
Overview
Report Status
Probable Cause
Event Type
Incident
Date
August 8, 1991
Injury Outcomes
No injuries (15 uninjured)
Location
Rowan Midland
Aircraft
Bell 412
Tail Number
N177EH
Operator
Era Aviation
Injuries
None
NTSB Number
FTW91IA143
DURING TAKEOFF FROM A MOVING VESSEL, THE PILOT LOST DIRECTIONAL CONTROL. HE ELECTED TO CONTINUE TO FLY IN AN EFFORT TO REACH AN OFFSHORE PLATFORM. AS DIRECTION CONTROL BECAME MORE UNSTABLE, THE CAPTAIN ORDERED THE FIRST OFFICER TO MAKE A WATER LANDING. FLOATS WERE INFLATED AND THE LANDING WAS MADE WITHOUT INCIDENT. ALL 15 ON BOARD WERE RECOVERED WITHOUT INCIDENT. EXAMINATION REVEALED THAT THE TAIL ROTOR DRIVE SHAFT HAD BEEN ASSEMBLED INCORRECTLY AND THAT THE QUILL ASSEMBLY HAD FAILED.
NTSB Probable Cause
THE MECHANIC'S FAILURE TO ASSEMBLE THE TAIL ROTOR DRIVE SHAFT CORRECTLY AND THE SUBSEQUENT FAILURE OF THE TAIL ROTOR DRIVE SHAFT. A FACTOR WAS THE LACK OF INSPECTION PROCEDURES FOR OFFSHORE MAINTENANCE.
Full Narrative
DURING TAKEOFF FROM A MOVING VESSEL, THE PILOT LOST DIRECTIONAL CONTROL. HE ELECTED TO CONTINUE TO FLY IN AN EFFORT TO REACH AN OFFSHORE PLATFORM. AS DIRECTION CONTROL BECAME MORE UNSTABLE, THE CAPTAIN ORDERED THE FIRST OFFICER TO MAKE A WATER LANDING. FLOATS WERE INFLATED AND THE LANDING WAS MADE WITHOUT INCIDENT. ALL 15 ON BOARD WERE RECOVERED WITHOUT INCIDENT. EXAMINATION REVEALED THAT THE TAIL ROTOR DRIVE SHAFT HAD BEEN ASSEMBLED INCORRECTLY AND THAT THE QUILL ASSEMBLY HAD FAILED.
Flight
Event TypeIncident
Event Time15:00 UTC
Nearest Airport0nm N
Runway0
Flight Plan FiledCvfr
Aircraft FireNo
Aircraft ExplosionNo
Aircraft
AircraftBell 412
Tail NumberN177EH
Aircraft CategoryHeli
OperatorEra Aviation
Operating RulePart 135
Engines2
Engine TypeTurboshaft
Engine DetailsP&W · PT6T-3B · Turboshaft · 1025
Seats15
People & Injuries
Injury SummaryNo injuries (15 uninjured)
Fatal0
Serious0
Minor0
Uninjured15
Total15
Crew 1Age 45 · First Class
Conditions
ConditionsVMC
LightDaylight
Wind45° @ 5 kt
Visibility20 sm
CeilingNone
Temperature / Dew Point0 C / 0 C
Altimeter0
Weather SourcePILO