ANC02LA123

NTSB accident investigation · de Havilland DHC-2 · Bethel, AK · September 20, 2002

Accident · No injuriesLimited investigationFinal report
Date
September 20, 2002, 08:15 local (16:15 UTC)
Place
Bethel, AK
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N144Qde Havilland DHC-2
Weather
Visual (VMC) · Dawn
Status
Completed · report July 23, 2003
Report
Approved by Office Director
NTSB office
Alaska Regional Office
Parties
Federal Aviation Administration
FAA report
20020920024539A
Case key
55765

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

On this page

Probable cause

The instructor pilot's inadequate preflight by his failure to remove all frost from the wings prior to takeoff, which resulted in an inadvertent stall and in-flight collision with terrain.

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 flightTakeoff - initial climb
Ice/frost removal from aircraft - inadequatePilot in command(cfi)Cause
Aircraft preflight - inadequatePilot in command(cfi)Cause
Airspeed - inadequatePilot in command(cfi)Cause
Stall - inadvertent
In flight collision with terrain/waterDescent - uncontrolled
Terrain condition - tundra

Analysis

The certificated flight instructor, seated in the right seat, reported that he was providing flight instruction/familiarization training a commercial pilot, seated in the left seat, in a float-equipped airplane. The instructor added that the accident flight was the first flight of the day. He said that just after takeoff, as the airplane climbed to about 50 feet above the water, the airplane began to buffet, and the right wing dropped. The airplane descended and subsequently struck an area of tundra-covered marshy terrain. The airplane sustained substantial damage to the wings, fuselage, and empennage. The instructor reported that a postaccident inspection of the airplane revealed an accumulation of frost on the wings.

Factual narrative

On September 20, 2002, about 0815 Alaska daylight time, a float-equipped de Havilland DHC-2 airplane, N144Q, sustained substantial damage during an in-flight collision with tundra-covered terrain during takeoff from a remote lake, located about 1 mile north of Bethel, Alaska. The airplane was being operated as a visual flight rules (VFR) local area instructional flight under Title 14, CFR Part 91, when the accident occurred. The airplane was being operated by Ptarmigan Air, Anchorage, Alaska. The first pilot, an airline transport certificated pilot/certificated flight instructor, seated in the right seat, and the second pilot, a commercial certificated pilot, seated in the left seat, were not injured. Visual meteorological conditions prevailed, and VFR company flight following procedures were in effect. The flight originated at the accident lake, about 0810.

During a telephone conversation with a National Transportation Safety Board investigator on September 20, the first pilot reported that he was providing flight instruction/familiarization training to the second pilot. The first pilot said that just after takeoff, as the airplane climbed to about 50 feet above the water, the airplane began to buffet, and the right wing dropped. The airplane descended and subsequently struck an area of tundra-covered marshy terrain. The airplane sustained substantial damage to the wings, fuselage, and empennage.

The first pilot reported that the accident flight was the first flight of the day. He added that a postaccident inspection of the airplane revealed an accumulation of frost on the wings.

Aircraft

Registration
N144Q
Reported as
de Havilland DHC-2
Category
Airplane
Serial number
1465
Airframe hours
7,850.3
Engine
Pratt & Whitney R-985, 450 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Operator
Ptarmigan Air, doing business as Ptarmigan Air
Registered owner
Sheryl Williams
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · September 19, 2002 · 0 hours before
Departed
BET · Bethel, AK
Destination
BET · Bethel, 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 · 2

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
40
Injuries
None
Certificates
Airline transport, Flight instructor
Airplane ratings
Single-engine sea, Multi-engine land, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--w/ waivers/lim
Last flight review
June 3, 2002
Seat
Right
Flight hours
9,600 total · 3,000 in this make and model · 9,600 as pilot in command · 360 in the last 90 days · 100 in the last 30 days · 0 in the last 24 hours
Role
Pilot
Age
26
Injuries
None
Certificate
Commercial
Airplane ratings
Single-engine land, Multi-engine land
Instrument ratings
Airplane
Medical
Class 3, Expired
Seat
Left

Weather

Conditions
Visual (VMC) · Dawn
Wind
Calm
Visibility
20 statute miles
Lowest ceiling
None
Temperature
28 °F

Docket · 2

The files NTSB released with the investigation on March 18, 2022, on NTSB’s docket system: statements, records, photos and specialists’ reports. 822 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.

Other investigations on N144Q · 1

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