ANC94LA137

NTSB accident investigation · Piper PA-18-150 · Port Alsworth, AK · September 15, 1994

Accident · No injuriesLimited investigationFinal report
Date
September 14, 1994, 20:15 local (Sep 15, 1994, 04:15 UTC)
Place
Port Alsworth, AK
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Initial climb
Aircraft
N3930ZPiper PA-18-150
Weather
Visual (VMC) · Day
Status
Completed · report May 10, 1995
Report
Approved by Office Director
NTSB office
Alaska Regional Office
FAA report
19940914027949A
Case key
2568

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 a positive rate of climb.

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 objectTakeoff - initial climb
Proper climb rate - not obtained/maintainedPilot in commandCause
Object - tree(s)

Analysis

The pilot reported that after liftoff from the remote lake, the airplane was climbing at the best angle of climb airspeed when it encountered 'dead air'. The airspeed began to decrease, and the airplane began to lose altitude. It then collided with several trees about 1/2 mi from the point of departure. The pilot described the wind conditions as light and variable.

Factual narrative

On September 14, 1994, at 2015 Alaska daylight time, a float equipped Piper PA-18 airplane, N3930Z, owned and operated by 4W Air of Soldotna, Alaska, a 14 CFR Part 135 on-demand commercial operator, collided with a tree during the takeoff climb from Nikabuna Lakes, approximately 35 miles southwest of Port Alsworth, Alaska. The commercial certificated pilot-in-command and his one passenger, the sole occupants, were not injured and the airplane sustained substantial damage. The 14 CFR Part 135 flight was conducted for the purpose of hunting for moose. A company VFR flight plan was in effect and visual meteorological conditions with calm winds prevailed at the time of the accident.

The pilot reported that after becoming airborne, the airplane was climbing at the best angle of climb airspeed. The airplane then encountered what the pilot described as "dead air". The airspeed began to decrease and the airplane lost altitude. While in a shallow left bank turn, the right wing of the plane collided with a tree about 1/2 mile from the departure point. The airplane then struck additional trees and descended to the ground.

Aircraft

Registration
N3930Z
Reported as
Piper PA-18-150
Category
Airplane
Serial number
18-7777
Airframe hours
2,284
Engine
Lycoming O-320-A2B, 150 horsepower, reciprocating
Damage
Substantial damage
Flight
Part 135
Operator
4w Air
Registered owner
Woodin, Bill
Airworthiness certificate
Standard, Normal
Last inspection
100 hour · September 9, 1993 · 52 hours before
Destination
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
28
Certificate
Commercial
Airplane ratings
Single-engine land, Single-engine sea
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--w/ waivers/lim
Seat
Front
Flight hours
1,248 total · 39 in this make and model · 1,155 as pilot in command · 230 in the last 90 days · 92 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
Calm
Visibility
20 statute miles
Lowest ceiling
3,000 ft overcast
Temperature
50 °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 N3930Z · 1

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