de Havilland DHC-2 N10395 accident, Nondalton, AK, Aug 21, 2001 · NTSB ANC01LA121

Probable cause

The pilot's inadequate compensation for gusty wind conditions. Factors associated with the accident were the pilot's inadequate weather evaluation, and wind gusts.

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 encounter with weatherTakeoff - initial climb

Weather evaluation - inadequatePilot in commandFactor

Weather condition - gustsFactor

Loss of control - in flightTakeoff - initial climb

Compensation for wind conditions - inadequatePilot in commandCause

In flight collision with terrain/waterDescent - uncontrolled

Terrain condition - water

Analysis

The certificated commerical pilot reported to the NTSB that just after takeoff, about 100 feet above the water, a very strong gust of wind rolled the wings of the float-equipped airplane about 90 degrees to the left. He said that he applied full right aileron in an attempt to regain control, but the airplane descended, and the left wing struck the surface of the water. As the airplane's left wing struck the surface of the water, the wing separated from the fuselage, pivoted the airplane 90 degrees to the left, and the right wing struck the water. Both floats were torn from the fuselage, and the airplane eventually sank in shallow water. The airplane sustained substantial damage to the fuselage, wings, and empennage. The pilot reported that wind conditions at the time of the accident were out of the northwest at 20 knots, with gusts to 30 knots.

Factual narrative

On August 21, 2001, about 1430 Alaska daylight time, a float-equipped de Havilland DHC-2 airplane, N10395, sustained substantial damage during takeoff from Six Mile Lake, Nondalton, Alaska. The airplane was being operated as a visual flight rules (VFR) on-demand passenger flight under Title 14, CFR Part 135, when the accident occurred. The airplane was owned by Ernest M. Brooks, and operated by Alaska Air Taxi, Inc., Anchorage, Alaska. The certificated commercial pilot, and the four passengers, were not injured. Visual meteorological conditions prevailed, and company visual flight rules (VFR) flight following procedures were in effect for the flight to Port Alsworth, Alaska.

During a telephone conversation with the National Transportation Safety Board investigator-in-charge on August 21, the pilot reported that just after takeoff, about 100 feet above the water, a very strong gust of wind rolled the wings of the airplane about 90 degrees to the left. He said that he applied full right aileron in an attempt to regain control, but the airplane descended, and the left wing struck the surface of the water. As the airplane's left wing struck the surface of the water, the wing separated from the fuselage, pivoted the airplane 90 degrees to the left, and the right wing stuck the water. Both floats were torn from the fuselage, and the airplane eventually sank in shallow water. The airplane sustained substantial damage to the fuselage, wings, and empennage.

The pilot reported that wind conditions at the time of the accident were out of the northwest at 20 knots, with gusts to 30 knots.

Aircraft

Registration: N10395
Reported as: de Havilland DHC-2
Category: Airplane
Serial number: 1354
Airframe hours: 16,445
Engine: P&W R-985, 450 horsepower, reciprocating
Damage: Substantial damage
Flight: Part 135
Operator: Jack Barber, doing business as Alaska Air Taxi, Inc.
Registered owner: Ernest M. Brooks
Airworthiness certificate: Standard, Normal
Last inspection: 100 hour · August 18, 2001 · 23 hours before
Departed: 5NN · Nondalton, AK
Destination: TPO · Port Alsworth, AK
Flight plan: Company VFR

N10395Registered now · Dehavilland BEAVER DHC-2S/N 1354 · Built 1959 Airframe modelDehavilland BEAVER DHC-2 Engine modelPratt & Whitney R-985 seriesReciprocating

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: 35
Injuries: None
Certificate: Commercial
Airplane ratings: Single-engine sea, Single-engine land
Instrument ratings: Airplane
Medical: Class 2, Valid Medical--no waivers/lim.
Last flight review: May 31, 2001
Seat: Left
Flight hours: 5,450 total · 2,000 in this make and model · 5,200 as pilot in command · 243 in the last 90 days · 139 in the last 30 days · 7 in the last 24 hours

Weather

Conditions: Visual (VMC) · Day
Wind: 300° at 20 knots, gusting 30
Visibility: 20 statute miles

FAA reports on this event · 1

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

Accident 20010821039669ADhav DHC2* · Nondalton, AK(-23) On August 21, 2001, a float equipped Dehavilland DHC-2, N10395, sustained substantial damage shortly after takeoff from six-mile lake, Nondalton, Alaska. Visual meteorological conditions prevailed for the part 135, passenger carrying flight operated by…Aug 21, 2001 · N10395 · Substantial damage

Other investigations on N10395 · 1

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

NTSB ANC85LA104Accident · No injuriesLimited investigationFinal reportUngalikthluk Rv, AKThe plt reported that when he was landing the float plane on a river, an extreme gust of wind cocked the acft causing loss of control. Subsequently, the acft struck a river bank & was damaged. The plt noticed that after the landing, the winds had changed,…Jun 22, 1985 · Substantial damage