ANC99LA140

NTSB accident investigation · Eurocopter AS-350B-2 · Juneau, AK · September 10, 1999

Accident · No injuriesLimited investigationFinal report
Date
September 10, 1999, 14:45 local (22:45 UTC)
Place
Juneau, AK
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Maneuvering
Aircraft
N6052CEurocopter AS-350B-2
Weather
Visual (VMC) · Day
Status
Completed · report August 10, 2000
Report
Approved by Office Director
NTSB office
Alaska Regional Office
FAA report
19990910046619A
Case key
47401

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

The pilot's failure to maintain altitude/clearance. Factors associated with the accident were flat light conditions, snow-covered terrain, and self-induced pressure to continue the search.

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/waterManeuvering
Altitude/clearance - not maintainedPilot in commandCause
Self-induced pressurePilot in commandFactor
Light condition - otherFactor
Terrain condition - snow coveredFactor

Analysis

The commercial helicopter pilot, with one passenger aboard, was conducting a search for an overdue company helicopter. While searching the upper portion of a glacial ice field, deteriorating weather conditions required the pilot to alter his search route. He said that he slowed the helicopter to 15 knots and attempted to use a mountain range on the right side of the helicopter for visual reference. He said: 'Visibility in front was enough to see all the way to the top of the Herbert (greater than three miles). The ceiling sloped down to the east 45 degrees with a height at the ridge of approximately 700 feet.' The pilot added that just seconds before the impact, he thought the helicopter was at least 500 feet above the surface. He said that 'flat light conditions' made it very difficult to see the topographical features of the ice field below. The helicopter struck the snow-covered ice field, slid about 75 feet, and the helicopter rolled over to the right. The helicopter sustained substantial damage to the fuselage, tail boom, and rotor system. After the accident, the pilot radioed for another company helicopter to pick them up. A second company helicopter, N6099Y, landed at the accident site, boarded the uninjured pilot and passenger, and continued the search. During the search, N6099Y also collided with the snow-covered ice field. See ANC99FA139, and ANC99LA141. The accident pilot did not possess an instrument rating, and the helicopter was not equipped with a radar altimeter.

Factual narrative

On September 10, 1999, about 1445 Alaska daylight time, a Eurocopter AS-350B-2 helicopter, N6052C, sustained substantial damage when it impacted the surface of the Juneau ice field, about 17 miles north of Juneau, Alaska, at 58.37.646 north latitude, 134.28.270 west longitude. The helicopter was being operated as a visual flight rules (VFR) search and rescue flight under Title 14, CFR Part 91, when the accident occurred. The helicopter was operated by Temsco Helicopters, Inc., Ketchikan, Alaska. The certificated commercial pilot and the one passenger aboard were not injured. Visual meteorological conditions prevailed at the time of departure, and company flight following procedures were in effect. The flight originated about 1345 from the Juneau International Airport, Juneau.

During an interview with the National Transportation Safety Board investigator-in-charge on September 11, the pilot reported that he was conducting a search for an overdue company helicopter. The pilot said that while searching the upper portion of the ice field, deteriorating weather conditions to the north and east required that he proceed south, and down the ice field. He stated that he slowed the helicopter to 15 knots and attempted to use a mountain range on the right side of the helicopter for visual reference. He said: "Visibility in front was enough to see all the way to the top of the Herbert (greater than three miles). The ceiling sloped down to the east 45 degrees with a height at the ridge of approximately 700 feet." The pilot added that just seconds before the impact, he thought the helicopter was at least 500 feet above the surface. He said that "flat light conditions" made it very difficult to see the topographical features of the ice field below. The helicopter struck the snow-covered ice field, slid about 75 feet, and the helicopter rolled over to the right.

The helicopter sustained substantial damage to the fuselage, tail boom, and rotor system.

After the accident, the pilot radioed for another company helicopter to pick them up. A second company helicopter, N6099Y, landed at the accident site, boarded the uninjured pilot and passenger, and continued the search. During the search, N6099Y also collided with the snow-covered ice field. See ANC99FA139, and ANC99LA141.

The accident pilot did not possess an instrument rating, and the helicopter was not equipped with a radar altimeter.

Aircraft

Registration
N6052C
Reported as
Eurocopter AS-350B-2
Category
Helicopter
Serial number
2586
Airframe hours
3,727
Engine
Turbomeca ARRIEL D1D, 732 horsepower, turbo shaft
Damage
Substantial damage
Flight
Part 91
Registered owner
Temsco Helicopters, Inc.
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · September 5, 1999 · 18 hours before
Departed
JNU · AK
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
27
Certificate
Commercial
Medical
Class 2, Valid Medical--no waivers/lim.
Seat
Right
Flight hours
2,396 total · 1,537 in this make and model · 2,336 as pilot in command · 170 in the last 90 days · 47 in the last 30 days · 4 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
180° at 5 knots
Visibility
6 statute miles
Lowest ceiling
700 ft overcast
Temperature
45 °F

Docket · 2

The files NTSB released with the investigation on July 28, 2000, on NTSB’s docket system: statements, records, photos and specialists’ reports. 653 KB 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.