ANC17CA038

NTSB accident investigation · Dehavilland DHC 2 · Dilllingham, AK · July 21, 2017

Accident · No injuriesData collectionFinal report
Date
July 21, 2017, 12:00 local (20:00 UTC)
Place
Dilllingham, AK
Injuries
3 uninjured
Damage
Substantial damage
Phase of flight
Takeoff
Aircraft
N364RADehavilland DHC 2
Defining event
Takeoff: Collision during takeoff/land
Weather
Visual (VMC) · Day
Status
Completed · report January 11, 2018
Report
Approved by Office Director
NTSB office
Alaska Regional Office
Parties
Federal Aviation Administration
FAA report
20170721012619A
Case key
95678

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 set the wing flaps to the "takeoff" position, which resulted in a longer-than-normal takeoff run and collision with terrain.

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.

Use of equip/info: use of equip/systemPersonnel issues › Task performance · PilotAll aircraft: 1,391 casesProbable cause
Flight control system: lE flap control systemAircraft › Aircraft systems · Incorrect use/operationAll aircraft: 3 casesProbable cause
TerrainEnvironmental issues › Physical environment · Effect on operationAll aircraft: 267 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 stated that he was departing on a postmaintenance flight check in a float-equipped airplane from a short water lane at a remote, unimproved seaplane base. While taxiing for departure, he left the wing flaps in the "up" position to aid in turning the airplane on the water. After aligning the airplane for the takeoff run, he applied full power, and the airplane accelerated onto the step. While attempting to rotate, he realized that he had forgotten to reset the wing flaps to the "takeoff" position. He attempted to reset the manually operated, hydraulically actuated wing flaps, but the incorrect flap setting led to a longer-than-normal takeoff run, and the airplane subsequently impacted the water lane's far bank, which resulted in substantial damage to the left wing and left-wing strut. The pilot reported that there were no preaccident mechanical anomalies with the airplane that would have precluded normal operation.

Factual narrative

The pilot stated that he was departing on a post-maintenance flight check in a float-equipped airplane from a short waterlane, at a remote unimproved seaplane base. While taxiing for departure, he left the wing flaps in the up position to aid in turning the airplane on the water. After aligning the airplane for the takeoff run, he applied full power and the airplane accelerated onto the step. While attempting to rotate, he realized that he had forgot to reset the wing flaps to the takeoff position. He attempted to reset the manually operated hydraulically actuated wing flaps, but the airplane impacted the waterlane's far bank sustaining substantial damage to the left wing, and left-wing strut. The pilot stated that there were no preaccident mechanical anomalies that would have precluded normal operation. In the recommendation section of the NTSB Accident/Incident Reporting Form 6120.1, the pilot stated that the accident may have been prevented if he would have utilized the airplane's checklist or rechecked the position of the wing flaps.

Aircraft

Registration
N364RA
Reported as
Dehavilland DHC 2 (MARKI)
Category
Airplane
Serial number
364
Built
1951
Airframe hours
15,677
Engine
P&W R-985 SERIES, 450 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
Bay Air Inc
Registered owner
Bay Air Inc
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · July 13, 2017
Departed
OZ3 · Dilllingham, AK
Destination
OZ3 · Dilllingham, AK
Airport
OZ3 · Shannon Pond
Equipment
ADS-B

Flight crew

As NTSB recorded them. NTSB leaves out names.

Role
Pilot
Age
58
Injuries
None
Certificate
Airline transport
Airplane ratings
Single-engine land, Single-engine sea, Multi-engine land
Instrument ratings
Airplane
Medical
Class 2, Without waivers/limitations
Last flight review
October 13, 2016
Seat
Left
Restraint
3-point
Flight hours
23,732 total · 6,972 in this make and model · 23,601 as pilot in command · 110 in the last 90 days · 110 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
180° at 5 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
64 °F, dew point 52 °F
Altimeter
29.96 inHg
Observed at
PADL, 3 nm away

Docket · 1

The files NTSB released with the investigation on December 8, 2017, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.4 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.