Aircraft Accident/Incident Report

Floriston, California 96111
Friday, September 10, 1993 12:40 PDT

NTSB Narrative Summary Released at Completion of Accident

The CFI was instructing his student in performing pinnacle approaches and landings to high density altitude mountainous locations. The student was initially flying. When the R22 had descended to 50 feet above the 6,100 ft MSL pinnacle, the CFI elected to made a go-around after observing that the terrain was not appropriate for the landing. The CFI took control of the helicopter, began turning right, and observed that the main rotor RPM decreased. The CFI attempted to recover RPM by reducing collective and rolling on full throttle. The R22 continued descending until colliding with a tree and terrain.

NTSB Probable Cause Narrative

the flight instructor's failure to maintain main rotor RPM after initiating a go-around from a pinnacle approach. A factor in the accident was the high density altitude condition.

Event Information

Type of Event Accident
Event Date 9/10/1993
Event Day of the Week Friday
Time of Event 1240
Event Time Zone Pacific Daylight Time
Event City FLORISTON
Event State CALIFORNIA
Event Country --
Zipcode of the event site 96111
Event Date Year 1993
Event Date Month 9
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 --
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness Unknown
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 9000
Lowest Non-Ceiling Height 6000
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) 30
Air Temperature at event time (in degrees celsius) 28
Dew Point at event time (in degress fahrenheit) 4
Wind Direction (degrees magnetic) 225
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) 8750
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) 1439
NTSB Notification Source --
NTSB Notification Date Sep 10 1993 12:00AM
NTSB Notification Time 1400
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 11 2000 1:39PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N47NH
NTSB Number LAX93LA348
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 R22B
Aircraft Series Identifier R22B
Aircraft Serial Number 1192
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 Annual
Date of Last Inspection Aug 31 1993 12:00AM
Airframe hours since last inspection --
Airframe Hours 3982
ELT Installed Unknown
ELT Activated Unknown
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name CHARLES WILLIAM ABY TRUST
Aircraft Owner Street Address 520 SALLY RIDE RD.
Aircraft Owner City CONCORD
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 94520
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 DRIVE
Operator City CONCORD
Operator State CA
Operator Country
Operator Zip code 94520
Operator Code HIAA
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) 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 1140
Departure Time Zone PDT
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 Approach
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 --