ANC22LA050

NTSB accident investigation · Dehavilland Beaver U-6A · Kokhanok, AK · June 26, 2022

Accident · No injuriesClass 4 · LimitedFinal report
Date
June 25, 2022, 18:00 local (Jun 26, 2022, 02:00 UTC)
Place
Kokhanok, AK
Injuries
7 uninjured
Damage
Substantial damage
Phase of flight
Takeoff
Aircraft
N600NLDehavilland Beaver U-6A
Defining event
Takeoff: Loss of control in flight
Weather
Visual (VMC) · Day
Status
Completed
Report
Approved by Office Director
Investigation class
Class 4 - Basic report with no Prelim publish
NTSB office
Alaska Regional Office
Parties
Federal Aviation Administration
FAA report
20220625012219A
Case key
105392

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 directional control during takeoff in gusting wind conditions which resulted in a loss of control and impact with the water.

Findings · 3

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Wind: gustsEnvironmental issues › Conditions/weather/phenomena · Effect on operationDehavilland BEAVER U-6A: 1 caseAll aircraft: 1,199 casesProbable cause
Performance/control parameters: directional controlAircraft › Aircraft oper/perf/capability · Not attained/maintainedDehavilland BEAVER U-6A: 3 casesAll aircraft: 3,958 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot reported that, as the float-equipped airplane accelerated on the water for takeoff, a gust of wind turned the airplane 90° to the left. The left float subsequently impacted a wave and the airplane rolled inverted. The airplane eventually sank and was not recovered. The pilot reported that there were no preaccident mechanical malfunctions or anomalies that would have precluded normal operation.

Aircraft

Registration
N600NL
Reported as
Dehavilland Beaver U-6A
Category
Airplane
Serial number
857
Built
1954
Airframe hours
14,104.3
Engine
P&W R-985 SERIES, 450 horsepower, reciprocating
Damage
Substantial damage
Flight
Business · Part 91
Operator
Newhalen Lodge Inc
Registered owner
Newhalen Lodge Inc
Airworthiness certificate
Standard, Normal
Last inspection
Annual · March 6, 2022
Destination
Same as departure
Flight plan
Company VFR
Airport
PVT · Private
Equipment
Handheld GPS

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
73
Injuries
None
Certificates
Airline transport, Commercial, Flight instructor
Airplane ratings
Multi-engine land, Single-engine sea, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, With waivers/limitations
Last flight review
August 27, 2021
Seat
Left
Flight hours
19,150 total · 10,000 in this make and model · 18,950 as pilot in command · 36 in the last 90 days · 36 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
150° at 6 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
57 °F, dew point 50 °F
Altimeter
30.27 inHg
Observed at
PAIL, 19 nm away
METAR
PAIL 260153Z 15006KT 10SM FU CLR 14/10 A3027 RMK AO2 SLP251 T01440100

Docket · 2

The files NTSB released with the investigation on October 20, 2022, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.5 MB 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.