LAX94LA236

NTSB accident investigation · Sharp Scorpion TOO · Beckwourth, CA · June 2, 1994

Accident · FatalLimited investigationFinal report
Date
June 2, 1994, 13:00 local (20:00 UTC)
Place
Beckwourth, CA
Injuries
1 fatal
Damage
Destroyed
Phase of flight
Enroute
Aircraft
N288JSSharp Scorpion TOO
Weather
Visual (VMC) · Day
Status
Completed · report December 7, 1994
Report
Approved by Office Director
FAA report
19940602013399A
Case key
28757

From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.

On this page

Probable cause

the failure of the tail rotor 'V' drive belt for undetermined reasons and the subsequent failure and separation of the tail rotor.

Sequence of events

NTSB’s coding before 2008: each occurrence and phase of flight, and the causes and factors under it. The codes are defined in NTSB’s coding manual.

Airframe/component/system failure/malfunctionCruise
Rotor system - separationCause
Loss of control - in flightCruise - normal
Aircraft control - not possiblePilot in command
In flight collision with terrain/waterDescent - uncontrolled

Analysis

Ground witnesses reported that the helicopter was cruising about 200 feet agl when popping sounds were heard. Parts then came off the helicopter and it descended rapidly to impact. Witnesses on the airport indicated this was the third flight of the day and that the builder/pilot may have been performing test flights. An FAA inspector reported that the tail rotor assembly was found about 90 yards from the main wreckage along with portions of a 'V' drive belt used to power the tail rotor. Color transfers similar to the drive belt material were found on the blades. The mode of belt failure was not determined. FAA records show the pilot held a private pilot certificate with an airplane single-engine land rating and did not hold a rotorcraft category rating. No evidence was found of a solo endorsement for helicopters. The last medical certificate issued to the pilot was dated March 8, 1988. No information was available concerning the last maintenance inspection.

Factual narrative

On June 2, 1994, about 1300 Pacific daylight time, a homebuilt experimental Sharp Scorpion Too helicopter, N288JS, sustained an in-flight separation of the tail rotor system and crashed about 1 mile west of Beckwourth, California. The helicopter was built, owned, and operated by the pilot. Visual meteorological conditions prevailed at the time and no flight plan was filed for the operation. The helicopter was destroyed in the accident sequence. The private pilot, the sole occupant, sustained fatal injuries. The flight originated from the Beckwourth airport on the day of the accident about 1230 as a presumed local area personal flight.

Ground witnesses reported that the helicopter departed from the Beckwourth airport and was cruising about 200 feet agl when popping sounds were heard. The witnesses observed parts come off the helicopter, then it descended rapidly to ground impact. Information from individuals on the airport indicated this was the third flight of the day and that the builder/pilot may have been performing test flights.

A Federal Aviation Administration (FAA) inspector from the Reno, Nevada, Flight Standards District Office responded to the accident site and examined the wreckage. He reported that the tail rotor assembly was found about 90 yards from the main wreckage along with portions of a 'V' drive belt, apparently used to power the tail rotor. Color transfers similar to the drive belt material were found on the blades. The inspector was unable to determine the mode of failure of the drive belt.

According to FAA records, the pilot held a private pilot certificate with an airplane single-engine land rating. The pilot did not hold a rotorcraft category rating and no evidence was found of a solo endorsement for helicopters. The last medical certificate issued to the pilot was dated March 8, 1988. No information was available concerning the last periodic inspection performed on the helicopter. FAA records disclosed that the helicopter was first issued an experimental airworthiness certificate in the amateur built category on December 27, 1987. The helicopter reportedly had accrued a total time of 66 hours.

Aircraft

Registration
N288JS
Reported as
Sharp Scorpion TOO (SCORPION T)
Category
Helicopter, amateur-built
Serial number
SH-1
Airframe hours
66
Engine
Rotorway RW-133, 160 horsepower, reciprocating
Damage
Destroyed
Flight
Personal · Part 91
Operator
James L. Sharp
Registered owner
James L. Sharp
Airworthiness certificate
Special, Experimental (Special)
Departed
O02

Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
67
Certificate
Private
Airplane ratings
Single-engine land
Medical
Expired
Toxicology
Performed
Flight hours
1,200 total · 66 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
220° at 20 knots
Visibility
30 statute miles
Lowest ceiling
None
Temperature
72 °F, dew point 28 °F
Altimeter
30.00 inHg
Observed at
TRK, 16 nm away

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.