Aircraft Accident/Incident Report

Verdi, Nevada 89439
Friday, July 30, 1993 12:29 PDT

NTSB Narrative Summary Released at Completion of Accident

THE HELICOPTER WAS ONE OF A FLIGHT OF FOUR HELICOPTERS CONDUCTING A MOUNTAIN FLYING COURSE WHICH CONSISTED OF EXECUTING PINNACLE LANDINGS AND TAKEOFFS. THE CFI ALLOWED THE DUAL STUDENT TO FOLLOW ANOTHER HELICOPTER ON ITS DEPARTURE FROM THE PINNACLE. THE HELICOPTER ENCOUNTERED THE PRECEDING HELICOPTER'S ROTOR WASH AND IMMEDIATELY TURNED RIGHT. THE STUDENT APPLIED LEFT PEDAL CORRECTIVE ACTION, BUT THE MAIN ROTOR RPM'S BEGAN TO DECAY. THE CFI ASSUMED THE CONTROLS AND IMMEDIATELY LOWERED THE COLLECTIVE AND APPLIED FULL THROTTLE, BUT THE REAR SKIDS STRUCK THE GROUND. THE CFI WAS ABLE TO REGAIN A LEVEL ATTITUDE, BUT THE HELICOPTER STRUCK SOME ROCKS AND CRASHED.

NTSB Probable Cause Narrative

THE INSTRUCTOR'S IMPROPER SUPERVISION OF THE FLIGHT; THE DUAL STUDENT'S IMPROPER IN-FLIGHT DECISION TO FOLLOW ANOTHER HELICOPTER ON DEPARTURE AND THE DUAL STUDENTS DELAY IN CORRECTING THE INADVERTENT YAW. FACTORS RELATED TO THIS ACCIDENT WAS THE INADVERTENT ENCOUNTER WITH THE WAKE TURBULENCE FROM THE PRECEDING DEPARTING HELICOPTER; THE DUAL STUDENT'S IMPROPER USE OF THE THROTTLE AND THE DUAL STUDENTS FAILURE TO MAINTAIN ADEQUATE ROTOR RPM.

Event Information

Type of Event Accident
Event Date 7/30/1993
Event Day of the Week Friday
Time of Event 1229
Event Time Zone Pacific Daylight Time
Event City VERDI
Event State NEVADA
Event Country --
Zipcode of the event site 89439
Event Date Year 1993
Event Date Month 7
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 Pilot
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 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) 24
Dew Point at event time (in degress fahrenheit) 4
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Light and Variable
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 None
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None 2
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 404
NTSB Notification Source --
NTSB Notification Date Jul 30 1993 12:00AM
NTSB Notification Time 1405
Fiche Number and/or location -used to find docket information 51605
Date of most recent change to record Dec 11 2000 1:29PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N549SM
NTSB Number LAX93LA308
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name ROBINSON
Aircraft Model R-22
Aircraft Series Identifier R-22
Aircraft Serial Number 1549
Certified Max Gross Weight 1370
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 2
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection 100 Hour
Date of Last Inspection Jun 30 1993 12:00AM
Airframe hours since last inspection 85
Airframe Hours 1795
ELT Installed No
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name CHARLES L. MARLOW
Aircraft Owner Street Address P.O. BOX 252
Aircraft Owner City NORCO
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 91760
Operator is an individual? --
Operator Name HELICOPTER ADVENTURES, INC.
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address 81 JOHN GLENN DR.
Operator City CONCORD
Operator State CA
Operator Country
Operator Zip code 94520
Operator Code HIAS
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) Instructional
Second Pilot on Board Yes
Departure Point Same as Event No
Departure Airport Code RNO
Departure City RENO
Departure State NV
Departure Country
Departure Time 1110
Departure Time Zone PDT
Destination Same as Local Flt --
Destination Airport Code TRK
Destination City TRUCKEE
Destination State CA
Destination Country
Specific Phase of Flight Takeoff
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 --