ANC06LA109

NTSB accident investigation · de Havilland DHC-2 MK.1 · Anaktuvuk Pass, AK · August 2, 2006

Accident · No injuriesLimited investigationFinal report
Date
August 1, 2006, 17:30 local (Aug 2, 2006, 01:30 UTC)
Place
Anaktuvuk Pass, AK
Injuries
6 uninjured
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N4040Wde Havilland DHC-2 MK.1
Weather
Visual (VMC) · Day
Status
Completed · report February 26, 2007
Report
Approved by Office Director
NTSB office
Alaska Regional Office
Parties
Fairbanks FSDO-01
FAA report
20060801015849A
Case key
64306

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 abort the takeoff at his predetermined reference point, which resulted in a collision with the shore during takeoff-initial climb, and structural damage to the airplane.

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/waterTakeoff - initial climb
Terrain condition - dirt bank/rising embankment
Aborted takeoff - not performedPilot in commandCause
Gear collapsedLanding - flare/touchdown

Analysis

The airline transport certificated pilot was transporting passengers from a remote lake in a float-equipped airplane under Title 14, CFR Part 135. He said that during takeoff he passed his predetermined point to abort the takeoff without becoming airborne, and felt that he had to proceed with the takeoff or hit the shoreline. The pilot said that he was able to become airborne, but struck the shore of the lake with the airplane's floats just after liftoff. He stated that he was concerned about damage to the floats from the impact with the shore, and elected to land on a hard surface runway at the destination airport. The float structure collapsed during landing, resulting in substantial damage to the fuselage. There were no known mechanical anomalies with the airplane prior to the accident.

Factual narrative

On August 1, 2006, about 1730 Alaska daylight time, a float-equipped, de Havilland DHC-2 Mk.1 airplane, N4040W, sustained substantial damage when it struck the shore during takeoff from a remote lake, about 50 miles south of Anaktuvuk Pass, Alaska. The airplane was being operated by Brooks Range Aviation, Bettles, Alaska, as a visual flight rules (VFR) passenger flight under Title 14, CFR Part 135, when the accident occurred. The airline transport certificated pilot and the five passengers were not injured. Visual meteorological conditions prevailed, and company flight following procedures were in effect.

During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on August 1, the Bettles Airport manager said the float-equipped accident airplane landed on the hard-surfaced runway at Bettles. The manager said the pilot told her that he had struck the shore during takeoff from a lake, and feared the floats would not support the airplane during a water landing, and elected to land on the hard-surface runway. The manager reported that during landing the float's supporting structure collapsed, and the airplane sat on its tail.

On August 3, the director of operations for the company told the IIC he believed that damage to the airplane was limited to the floats and support structure, however the airplane had been put back on wheels, and the airplane was being ferried to a repair facility to have the fuselage examined and repaired, if necessary.

On August 10, an FAA maintenance inspector who examined the repairs made to the airplane, told the IIC that an aft fuselage bulkhead had to be cut and spliced at the bottom, and that several additional fuselage stringers had to be cut and repaired, or replaced.

In a written statement to the NTSB dated August 27, the pilot wrote that he "hesitated" at the takeoff abort point long enough that he felt he had no choice but to continue the takeoff, and that the floats hit the bank just as the airplane became airborne.

Aircraft

Registration
N4040W
Reported as
de Havilland DHC-2 MK.1
Category
Airplane
Serial number
1147
Airframe hours
127,000
Engine
Pratt & Whitney Canada R-985-14G, 450 horsepower, reciprocating
Damage
Substantial damage
Flight
Part 135
Operator
Brooks Range Aviation Inc, doing business as Brooks Range Aviation
Registered owner
Jesperson Aircraft Services Inc.
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · July 1, 2006 · 56 hours before
Departed
Anaktuvuk Pass, AK
Destination
PABT · Bettles, 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
62
Injuries
None
Certificates
Flight instructor, Airline transport
Airplane ratings
Single-engine sea, Multi-engine land, Single-engine land, Multi-engine sea
Instrument ratings
Airplane
Medical
Class 2, Without waivers/limitations
Last flight review
June 1, 2006
Seat
Left
Flight hours
16,631 total · 422 in this make and model · 8,610 as pilot in command · 99 in the last 90 days · 97 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Visibility
10 statute miles
Lowest ceiling
None
Temperature
61 °F

FAA reports on this event · 1

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

Other investigations on N4040W · 1

Matched to the same aircraft by N-number and date.