Sonoma County Airport
Aircraft Accident/Incident Report

Santa Rosa, California 95043
Friday, December 29, 1989 11:30 PST

NTSB Narrative Summary Released at Completion of Accident

THE PILOT EXECUTED AN IMMEDIATE LEFT DOWNWIND CLIMBING TURN WHEN HE DEPARTED THE HELIPAD AND EXPERIENCED A LOSS OF TAIL ROTOR EFFECTIVENESS. BEFORE DEPARTING, THE PILOT FAILED TO ACCOUNT FOR THE DOWNWIND TURN AND THE HELICOPTER'S EXCEEDING THE MAXIMUM GROSS WEIGHT. THE POST ACCIDENT INVESTIGATION DISCLOSED THE LATERAL TRIM MOTOR EXCEEDED ITS PHYSICAL EXTENSION LIMITS WHICH INDICATES THAT THE TRIM MOTOR WAS OPERATING DURING THE IMPACT SEQUENCE WHEN ITS AIRFRAME ATTACHMENT POINT WAS BROKEN.

NTSB Probable Cause Narrative

THE PILOT'S IMPROPER PREFLIGHT PLANNING/DECISION WHICH RESULTED IN THE LOSS OF TAIL ROTOR EFFECTIVENESS. CONTRIBUTING TO THE ACCIDENT WAS THE PILOT ALLOWING THE MAXIMUM GROSS WEIGHT OF THE AIRCRAFT TO BE EXCEEDED, AND THE TAILWIND.

Event Information

Type of Event Accident
Event Date 12/29/1989
Event Day of the Week Friday
Time of Event 1130
Event Time Zone Pacific Standard Time
Event City SANTA ROSA
Event State CALIFORNIA
Event Country --
Zipcode of the event site 95043
Event Date Year 1989
Event Date Month 12
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport SONOMA COUNTY
Event Location Nearest Airport ID STS
Indicates whether the acc/inc occurred off or on an airport On Airport
Distance from airport in statute miles 0
Degrees magnetic from airport 0
Airport Elevation 125
Weather Briefing Completeness Unknown
Investigator's weather source Weather Observation Facility
Time of the weather observation 1132 Pacific Standard Time
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID
Elevation of weather observation facility 125
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation PST
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) 30
Air Temperature at event time (in degrees celsius) 15
Dew Point at event time (in degress fahrenheit) 3
Wind Direction (degrees magnetic) 310
Variable Wind Indicator Unknown
Wind Speed (knots) 5
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 30
Density Altitude (feet) 125
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 3
Injury Total None --
Injury Total Serious 1
Injury Total All 5
Investigating Agency NTSB
NTSB Docket Number (internal use) 2273
NTSB Notification Source --
NTSB Notification Date Dec 29 1990 12:00AM
NTSB Notification Time 1230
Fiche Number and/or location -used to find docket information 42178
Date of most recent change to record Dec 13 2000 1:15PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N1604L
NTSB Number LAX90FA060
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 McDonnell Douglas
Aircraft Model 369E
Aircraft Series Identifier 369E
Aircraft Serial Number 0266E
Certified Max Gross Weight 3000
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 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection 100 Hour
Date of Last Inspection Nov 21 1989 12:00AM
Airframe hours since last inspection --
Airframe Hours 367
ELT Installed No
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name JOHN M. & ONA R. ROTH
Aircraft Owner Street Address 2280 AIRPORT BOULEVARD
Aircraft Owner City SANTA ROSA
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 95401
Operator is an individual? --
Operator Name INTERWEST, INC.
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address
Operator City
Operator State
Operator Country
Operator Zip code
Operator Code
Owner has at least one certificate None
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) Business
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code STS
Departure City
Departure State
Departure Country
Departure Time 1130
Departure Time Zone PST
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 Takeoff
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 --