Aircraft Accident/Incident Report

Tahoe City, California 96145
Friday, August 15, 1997 10:38 PDT

NTSB Narrative Summary Released at Completion of Accident

The public-use helicopter was transporting fire fighting personnel to a nearby forest fire at a small lake in the Sierra Nevada Mountains. The pilot said he calculated the allowable load for the hottest time of the day when he reported for work that morning. After dispatch for the fire mission, the pilot flew to the small lake where he determined that the area, 'appeared large enough to land and that the obstructions were fifty-foot tall trees.' He made an approach over the lake and landed on the beach and was told that they were no longer needed. The pilot said that as he lifted off from the lake edge he ran out of blade pitch and available power as he tried to climb above the trees and was forced to reverse direction. At the middle of the turn the aircraft began descending rapidly toward the water, and he attempted to accelerate the aircraft and pulled power until the rotor rpm began to droop. The helicopter settled into the lake with about 10 knots of forward airspeed. The pilot said the helicopter remained upright on the water with the skids immersed and a dropped main rotor rpm. The pilot reduced collective and recovered rpm with the intention of hovering the helicopter back to the beach area. After the rpm returned to normal, he increased collective, and the helicopter rolled to the right and sank inverted. Review of the cargo manifest, load calculation sheet, and hover ceiling chart show that the helicopter was about 800 pounds over the hover out of ground effect ceiling for the temperature and pressure altitude. The density altitude was computed to be approximately 9,500 feet.

NTSB Probable Cause Narrative

The pilot's decision to attempt a takeoff in environmental conditions which exceeded the helicopter's performance capability, and his improper use of the collective, which caused a decay of the main rotor rpm, the collision with the lake, and the subsequent rollover. Factors in the accident were the high density altitude and the confined area.

Event Information

Type of Event Accident
Event Date 8/15/1997
Event Day of the Week Friday
Time of Event 1038
Event Time Zone Pacific Daylight Time
Event City TAHOE CITY
Event State CALIFORNIA
Event Country --
Zipcode of the event site 96145
Event Date Year 1997
Event Date Month 8
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 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) 20
Dew Point at event time (in degress fahrenheit) 8
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Light and Variable
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 30
Density Altitude (feet) 9500
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 1
Injury Total None 6
Injury Total Serious --
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 793
NTSB Notification Source --
NTSB Notification Date Aug 15 1997 12:00AM
NTSB Notification Time 1115
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 8 2000 12:30PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N205DF
NTSB Number LAX97TA289
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed Company VFR
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Bell
Aircraft Model UH-1H
Aircraft Series Identifier UH-1H
Aircraft Serial Number 64-13370
Certified Max Gross Weight 9500
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 10
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection AAIP
Date of Last Inspection Jun 16 1997 12:00AM
Airframe hours since last inspection 60
Airframe Hours 5973
ELT Installed Yes
ELT Activated Unknown
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name NEVADA DIVISION OF FORESTRY
Aircraft Owner Street Address 123 W. NYE LANE, SUITE 142
Aircraft Owner City CARSON CITY
Aircraft Owner State NV
Aircraft Owner Country
Aircraft Owner Zipcode 89710
Operator is an individual? --
Operator Name USDA / FOREST SERVICE
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address
Operator City WASHINGTON
Operator State DC
Operator Country
Operator Zip code 20250
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) Public Use
Second Pilot on Board No
Departure Point Same as Event No
Departure Airport Code MEV
Departure City MINDEN
Departure State NV
Departure Country
Departure Time 1011
Departure Time Zone PDT
Destination Same as Local Flt crash at destination city
Destination Airport Code
Destination City
Destination State NV
Destination Country
Specific Phase of Flight Takeoff
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:34AM
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 --