Aircraft Accident/Incident Report

Corpus Christi, Texas 78406
Saturday, April 27, 1991 8:30 CDT

NTSB Narrative Summary Released at Completion of Accident

A COMMERCIAL PILOT WAS MANEUVERING A HELICOPTER TO CONTROL A HERD OF CATTLE. THE PILOT NOTICED AN INTERMITTENT BINDING IN THE LEFT QUADRANT OF THE CYCLIC CONTROL. HE NOTIFIED HIS FLIGHT LEADER OF HIS INTENTIONS TO LAND AND INSPECT THE HYDRAULIC SERVOS IN THE FLIGHT CONTROL SYSTEM, AND INITIATED A PRECAUTIONARY LANDING CLOSE TO THEIR MAINTENANCE SUPPORT VEHICLE. DURING THE LANDING FLARE, THE HELICOPTER PITCHED SHARPLY TO THE RIGHT REAR AS THE LATERAL CYCLIC CONTROL BECAME LOCKED. THE PILOT APPLIED FULL RIGHT PEDAL TO TRY TO CUSHION THE LANDING AND PREVENT THE HELICOPTER FROM ROLLING. THE HELICOPTER WAS DESTROYED UPON IMPACT WITH THE MESQUITE TREES. THE FAILED LATERAL SERVO HAD BEEN REPLACED BY AN UNQUALIFIED PERSON PRIOR TO THIS FLIGHT.

NTSB Probable Cause Narrative

THE INITIAL RESTRICTED MOVEMENT AND EVENTUAL LOCKING OF THE CYCLIC CONTROL AS A RESULT OF THE FAILURE OF THE LATERAL SERVO. A FACTOR WAS THE INSTALLATION OF THE FAILED COMPONENT BY AN UNQUALIFIED PERSON.

Event Information

Type of Event Accident
Event Date 4/27/1991
Event Day of the Week Saturday
Time of Event 830
Event Time Zone Central Daylight Time
Event City CORPUS CHRISTI
Event State TEXAS
Event Country --
Zipcode of the event site 78406
Event Date Year 1991
Event Date Month 4
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 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 900
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Unknown
Sky Condition for Lowest Ceiling Overcast
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 2
Air Temperature at event time (in degrees celsius) -18
Dew Point at event time (in degress fahrenheit) -18
Wind Direction (degrees magnetic) 130
Variable Wind Indicator Unknown
Wind Speed (knots) 12
Wind Velocity Indicator Unknown
Wind Gust Indicator Unknown
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) --
Density Altitude (feet) 0
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury Minor
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor 2
Injury Total None --
Injury Total Serious --
Injury Total All 2
Investigating Agency NTSB
NTSB Docket Number (internal use) 1227
NTSB Notification Source --
NTSB Notification Date --
NTSB Notification Time 0
Fiche Number and/or location -used to find docket information 44331
Date of most recent change to record Dec 18 2002 11:28AM
User who most recently changed record NTSB\GIUV
Basic weather conditions Instrument Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N1195W
NTSB Number FTW91LA064
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Destroyed
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name BELL
Aircraft Model 47G4
Aircraft Series Identifier 47G4
Aircraft Serial Number 3348
Certified Max Gross Weight 2950
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 3
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Unknown
Date of Last Inspection --
Airframe hours since last inspection 0
Airframe Hours --
ELT Installed No
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name W. J. TILLER
Aircraft Owner Street Address ROUTE 4, BOX 300A
Aircraft Owner City ALICE
Aircraft Owner State TX
Aircraft Owner Country
Aircraft Owner Zipcode 78332
Operator is an individual? --
Operator Name W. J. TILLER
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address ROUTE 4, BOX 300A
Operator City ALICE
Operator State TX
Operator Country
Operator Zip code 78332
Operator Code 210-
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 --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Aerial Observation
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code
Departure City
Departure State
Departure Country
Departure Time 800
Departure Time Zone CDT
Destination Same as Local Flt dest & departure same, accident can occur anywhere
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 10:35AM
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 --