FTW94FA224

NTSB accident investigation · Aerospatiale AS 350B-2 · Granite, CO · July 10, 1994

Accident · FatalField investigationFinal report
Date
July 9, 1994, 19:48 local (Jul 10, 1994, 01:48 UTC)
Place
Granite, CO
Injuries
2 fatal, 3 minor; on the ground: 3 minor
Damage
Destroyed
Phase of flight
Maneuvering
Aircraft
N95LGAerospatiale AS 350B-2
Weather
Visual (VMC) · Day
Status
Completed · report July 11, 1995
Report
Approved by Office Director
FAA report
19940709017929A
Case key
18910

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

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Probable cause

Failure of the pilot to assure main rotor clearance from sloping terrain while in a hover. The terrain condition was a related factor.

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.

In flight collision with terrain/waterHover
Terrain condition - mountainous/hillyFactor
Clearance - not maintainedPilot in commandCause

Analysis

The air ambulance (EMS) helicopter was dispatched to pick up an injured hiker on a 14,000' mountain. Terrain at the pickup point was at an elevation of about 12,200' and sloped approximately 35 degrees. Ground rescue personnel said the pilot advised them he would place the helicopter's right skid on the mountain slope to allow them to load the patient on the downhill side. As the helicopter hovered above them, the main rotor blades struck rocks. The helicopter then went over their heads, crashed, and subsequently tumbled about 800' down the mountain.

Factual narrative

History of flight

On July 9, 1994, at 1948 mountain daylight time, N95LG, an Aerospatiale AS350 B2 Ecureuil, was destroyed during hover 10 miles southwest of Granite, Colorado. The commercial pilot and a flight nurse were fatally injured, and three ground personnel received minor injuries. Visual meteorological conditions prevailed for the CFR part 135 flight.

The following is based on the pilot/operator report and interviews with ground rescuers. The helicopter, operating as an air ambulance, was dispatched from Provenant Medical Center in Frisco, Colorado, to 14,003-foot Mount Huron, near Granite, to pick up an injured hiker.

Ground rescue personnel said the pilot was in radio contact with them as he made his approach at the 12,200 foot level. The pilot advised them he would place the helicopter's right skid on the mountain slope to allow them to load the patient on the downhill side. Rescuers said they were beneath the rotor disc and were shielding their faces from flying debris when they heard "chopping" noises. They saw the main rotor blades strike the rocks and saw the helicopter flip over their heads and tumble down the mountain, coming to rest 800 feet away at the 11,400 foot level.

Medical and pathological information

An autopsy (report P-94-84) was performed on the pilot by Pathologists Professional Corporation, Pueblo, Colorado. FAA's Civil Aeromedical Institute also performed a toxicological screen, the results of which are attached to this report.

Tests and research

Examination of the accident site revealed the slope to be approximately 35 degrees. Using the flight manual's three dimensional scale drawing, three lines were drawn from the center of the helicopter, the center of the pilot's seat, and the edge of the right skid, and extended to the tip of the rotor blade. Angles formed by the intersection of these lines with the horizontal plane measured approximately 28 degrees, 28.5 degrees, and 29 degrees, respectively.

Additional information

The wreckage was released to the operator on July 10, 1994.

Aircraft

Registration
N95LG
Reported as
Aerospatiale AS 350B-2
Category
Helicopter
Serial number
2389
Airframe hours
2,905
Engine
Turbomeca ARRIEL 1D1, 625 horsepower, turbo shaft
Damage
Destroyed
Flight
Part 91
Operator
Rocky Mountain Helicopters Inc, doing business as Flight For Life
Registered owner
Geneva Transport Eqpt. Corp.
Airworthiness certificate
Standard, Normal
Last inspection
AAIP · June 29, 1994 · 12 hours before
Departed
91CO · Frisco, CO
Flight plan
Company VFR

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
49
Certificate
Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Helicopter
Medical
Class 2, Valid Medical--w/ waivers/lim
Seat
Right
Toxicology
Performed
Flight hours
15,207 total · 175 in this make and model · 31 in the last 90 days · 17 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
320° at 8 knots
Visibility
30 statute miles
Lowest ceiling
7,500 ft broken
Temperature
73 °F, dew point 28 °F
Altimeter
30.00 inHg
Observed at
LXV, 18 nm away

Docket · 18

The files NTSB released with the investigation on June 5, 1995, on NTSB’s docket system: statements, records, photos and specialists’ reports. 2.7 MB in all.

FAA reports on this event · 1

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