ANC02LA081

NTSB accident investigation · MBB BO-105S · Deadhorse, AK · July 23, 2002

Accident · No injuriesLimited investigationFinal report
Date
July 23, 2002, 15:15 local (23:15 UTC)
Place
Deadhorse, AK
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Landing
Aircraft
N491HLMBB BO-105S
Weather
Visual (VMC) · Day
Status
Completed · report April 1, 2003
Report
Approved by Office Director
NTSB office
Alaska Regional Office
Parties
FAA-AL-FAI FSDO 01
FAA report
20020723016189A
Case key
55285

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 correct a settling-with-power condition during a helicopter landing flare/touchdown, resulting in a hard landing and roll over.

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.

Loss of control - in flightLanding - flare/touchdown
Settling with power - not correctedPilot in commandCause
Hard landingLanding - flare/touchdown
Terrain condition - tundra
Roll overLanding - flare/touchdown

Analysis

The commercial certificated pilot departed a survey camp in a high skid-equipped helicopter, on an air taxi flight to survey potential exploration sites. The director of operations said the pilot told him that he was flying about 70 feet above the ground at 50 knots when he began a descending 180 degree left turn to land in an area of flat open tundra. The pilot indicated the airspeed decreased during the turn, and the helicopter shuddered and developed a high rate of descent. The pilot applied collective pitch and power, but the rate of descent increased. The right landing gear skid contacted the ground, and the helicopter rolled onto its right side. The pilot told the director of operations that the wind conditions were about 8 knots from the northeast.

Factual narrative

On July 23, 2002, about 1515 Alaska daylight time, a high skid-equipped Messerschmitt Bolkow Blohm (MBB) BO-105S helicopter, N491HL, sustained substantial damage when it collided with tundra-covered ground after developing a high rate of descent during the landing flare in a remote area, about 70 miles south-southwest of Deadhorse, Alaska. The helicopter was being operated as a visual flight rules (VFR) domestic on-demand passenger flight under Title 14, CFR Part 135, when the accident occurred. The helicopter was operated by Air Logistics of Alaska Inc., Fairbanks, Alaska. The commercial certificated pilot, and the sole passenger, were not injured. Visual meteorological conditions prevailed. A VFR flight plan was filed.

During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), on July 24, the director of operations for the operator reported the pilot departed a survey camp area known as Happy Valley, located about 20 miles south of Deadhorse along the Sagavanirktok River, on a flight to survey potential exploration sites. The director of operations said the pilot told him that he was flying about 70 feet above the ground at 50 knots. The pilot then began a descending 180 degree left turn to land in an area of flat open tundra. During the turn, the pilot began decreasing the airspeed. The helicopter shuddered and developed a high rate of descent. The pilot applied collective pitch and power, but the rate of descent increased. The right landing gear skid contacted the ground, and the helicopter rolled onto its right side. The pilot told the director of operations that the wind conditions were about 8 knots from the northeast.

Aircraft

Registration
N491HL
Reported as
MBB BO-105S
Category
Helicopter
Serial number
S-664
Airframe hours
10,120
Engine
Allison 250-C20B, 420 horsepower, turbo shaft
Damage
Substantial damage
Flight
Part 135
Registered owner
Air Logistics Of Alaska Inc.
Airworthiness certificate
Standard, Normal
Last inspection
AAIP · July 15, 2002 · 13 hours before
Departed
Deadhorse, AK
Destination
Deadhorse, AK
Flight plan
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
45
Injuries
None
Certificate
Commercial
Instrument ratings
Helicopter
Medical
Class 1, Valid Medical--w/ waivers/lim
Last flight review
May 15, 2002
Seat
Right
Flight hours
6,151 total · 105 in this make and model · 5,291 as pilot in command · 120 in the last 90 days · 90 in the last 30 days · 4 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
40° at 8 knots
Visibility
10 statute miles
Lowest ceiling
600 ft overcast
Temperature
37 °F
Altimeter
29.95 inHg

Docket · 1

The files NTSB released with the investigation on December 9, 2002, on NTSB’s docket system: statements, records, photos and specialists’ reports. 530 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.