ANC93LA178

NTSB accident investigation · Piper PA-18-150 · Prudhoe Bay, AK · September 13, 1993

Accident · No injuriesLimited investigationFinal report
Date
September 13, 1993, 15:00 local (23:00 UTC)
Place
Prudhoe Bay, AK
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N3996ZPiper PA-18-150
Weather
Visual (VMC) · Day
Status
Completed · report June 30, 1994
Report
Approved by Office Director
NTSB office
Alaska Regional Office
FAA report
19930913037829A
Case key
2428

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

Fluid fuel contamination as a result of the pilot-in-commands improper preflight planning/preparation.

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 engine power(partial) - nonmechanicalApproach
Fluid,fuel - contaminationCause
Preflight planning/preparation - improperPilot in commandCause
Forced landingDescent - emergency
Nose overLanding

Analysis

The pilot reported that the plane's engine suddenly lost a substantial amount of power approximately two hundred feet from the approach end of the remote tundra strip. The airplane landed short, bounced, and the engine regained some RPM. A go-around was attempted but the engine lost power again. The pilot performed a forced landing near the end of the strip and used heavy wheel breaking. The plane nosed over onto its back. The pilot said that he drained the plane's fuel tanks and engine sumps prior to conducting the flight and found no contamination. No further problems were experienced with the engine during the approximate 8 hour ferry flight to anchorage, Alaska. No abnormalities with the engine were noted during the teardown examination. The pilot said that the loss of power was probably caused by the engine ingesting a small amount of water.

Factual narrative

On September 13, 1993, at 1500 Alaska daylight time, a tundra tire wheel equipped Piper Pa-18-150 airplane, N3996Z, owned and operated by the pilot-in-command, doing business as Arctic Wilderness Lodge, crashed on a remote tundra strip approximately 80 miles south of Prudhoe Bay, Alaska. The commercial pilot, the sole occupant, was not injured, and the airplane sustained substantial damage. At the time of the mishap, the airplane was being operated under 14 CFR Part 91 as a business flight. The flight last departed Happy Valley Lodge, approximately 7 miles from the mishap site, near the Toolik River. The pilot was attempting to land at the site to recover moose meat belonging to a hunting party. A company VFR flight plan was in effect and visual meteorological conditions prevailed.

The pilot told the NTSB Investigator-in-Charge, during a phone conversation on the afternoon of September 14, 1993, that approximately 200 feet from the approach end of the landing strip, the engine lost power and "sputtered as if someone had pulled the fuel mixture control". He pumped the engine throttle control several times but got only a minimal increase in RPM's. Upon touching down short of the landing strip, the airplane bounced and the engine regained additional RPM's. He then attempted to go-around but the engine lost power again. The pilot reported that the subsequent forced landing near the end of the strip required the use of heavy wheel breaking which resulted in the plane nosing over onto its back.

The pilot said that he drained the wing and engine fuel sumps prior to commencing the flight, about one hour earlier, and observed no contamination. At the time of the mishap, he believed that the left and right wing fuel tanks were each one quarter full and the belly tank contained 4 to 5 gallons of 100LL aviation gasoline.

The plane was sufficiently repaired and ferried to the Merrill Field Airport in Anchorage, Alaska, approximately eight flight hours away. During the flight, no problems were experienced with the powerplant. A subsequent tear down and inspection of the engine, including the carburetor, found nothing that would have contributed to the power interruption. The pilot reported that given that there were no problems found with the engine, the interruption in power was probably caused by the engine injesting a small amount of water.

Aircraft

Registration
N3996Z
Reported as
Piper PA-18-150
Category
Airplane
Serial number
18-1806
Airframe hours
6,200
Engine
Lycoming O-320, 150 horsepower, reciprocating
Damage
Substantial damage
Flight
Business · Part 91
Registered owner
David F. Neel
Airworthiness certificate
Standard, Normal
Last inspection
Annual · June 25, 1993 · 78 hours before
Departed
Happy Valley, 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
44
Certificate
Commercial
Airplane ratings
Single-engine land, Single-engine sea
Medical
Class 2, Valid Medical--w/ waivers/lim
Seat
Front
Flight hours
3,300 total · 2,250 in this make and model · 3,300 as pilot in command · 210 in the last 90 days · 32 in the last 30 days · 1 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Visibility
99 statute miles
Lowest ceiling
None
Temperature
45 °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 N3996Z · 3

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