ANC96LA134

NTSB accident investigation · Cessna 180 · Port Alsworth, AK · August 30, 1996

Accident · Serious injuriesLimited investigationFinal report
Date
August 30, 1996, 15:30 local (23:30 UTC)
Place
Port Alsworth, AK
Injuries
1 serious, 1 minor, 1 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N8241VCessna 180
Weather
Visual (VMC) · Day
Status
Completed · report February 18, 1997
Report
Approved by Office Director
NTSB office
Alaska Regional Office
FAA report
19960830029869A
Case key
2889

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 fuel starvation caused by the unporting of the right fuel tank, and the pilot's inadequate preflight by not dipping the fuel tank to ensure sufficient fuel quantity to prevent the unporting.

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(total) - nonmechanicalCruise
Weather condition - turbulence
Fuel system - starvationCause
Aircraft preflight - inadequatePilot in commandCause
Forced landingEmergency descent/landing
Nose overEmergency descent/landing
Terrain condition - swampy

Analysis

The pilot had landed at a field site to pick up two passengers. After the landing, he drained the fuel from the left fuel tank to store for future use. The operator stated this is their normal practice, and as a result, operate the airplanes with the fuel selector valve in the right fuel tank position. When the airplane was approximately 5 minutes from the destination, the engine stopped producing power. The airplane landed and nosed over. Subsequent examination showed that the right fuel tank contained 7.3 gallons of usable fuel and the left fuel tank contained 3.1 gallons of usable fuel. The engine was started and it operated normally. The passengers stated the pilot did not dip the fuel tank prior to departure and that the return flight was turbulent.

Factual narrative

On August 30, 1996, at 1530 Alaska daylight time a wheel equipped Cessna 180 airplane, N8241V, registered to and operated by Lake Clark Air Inc., experienced a loss of engine power and subsequent forced landing while en route from the Mulchatna River to Port Alsworth, Alaska. The air taxi flight, operating under 14 CFR Part 135, departed the Mulchatna River area with two hunters on board. The destination was Port Alsworth. No flight plan was filed and visual meteorological conditions prevailed. The certificated airline transport pilot was not injured, one passenger sustained serious injuries and one passenger received minor injuries. The airplane was substantially damaged.

According to the passengers' statements, the pilot drained approximately 50 gallons of fuel from the airplane after landing. They said the pilot drained the left fuel tank dry. The operator stated that the airplane holds 84 gallons of fuel. It is their practice that upon reaching a field site, they drain the left fuel tank and store the fuel for future use. As a result, the company practice is to operate the airplane's fuel selector valve in the right fuel tank position. According to the passengers, the pilot did not dip the fuel tank prior to departure. They stated that he did not give them a passenger briefing prior to departure. The passengers indicated that the flight was turbulent.

While in cruise flight, and 5 minutes from the destination, the airplane's engine stopped producing power. The propeller continued to windmill during the descent. The pilot indicated on the NTSB Form 6120.1/2 that he applied carburetor heat, pushed the mixture full rich, pushed the throttle full forward, and placed the fuel selector in the "both" position. He landed the airplane and during the landing roll the airplane "flipped" over.

Subsequent examination of the airplane on September 4, 1996, by Federal Aviation Administration Flight Standards District Office Inspector, Mr. Gerald Martelli, showed that with the airplane in a level attitude there was only 7/16 of an inch of fuel covering the bottom of the right fuel tank. The fuel was drained from the right fuel tank through the gascolator. A total of 7.3 gallons of fuel was drained. The left fuel tank was drained through the gascolator and it yielded 3.1 gallons of fuel. The fuel was returned to their respective tanks and the engine was started. The engine started and operated normally.

Aircraft

Registration
N8241V
Reported as
Cessna 180
Category
Airplane
Serial number
18051743
Airframe hours
9,357
Engine
Continental O-470-R25, 230 horsepower, reciprocating
Damage
Substantial damage
Flight
Part 135
Operator
Lake Clark Air Inc.
Registered owner
Glen & Jean Alsworth
Airworthiness certificate
Standard, Normal
Last inspection
Annual · August 20, 1996 · 36 hours before
Departed
Mulchatna River, AK
Destination
5NW · 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
29
Certificates
Commercial, Airline transport, Flight instructor
Airplane ratings
Single-engine land, Single-engine sea, Multi-engine land
Instrument ratings
Airplane
Medical
Class 1, Valid Medical--w/ waivers/lim
Seat
Left
Flight hours
4,630 total · 20 in this make and model · 2,850 as pilot in command · 120 in the last 90 days · 90 in the last 30 days · 2 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Wind
Variable at 4 knots
Visibility
25 statute miles
Lowest ceiling
2,500 ft broken
Temperature
64 °F

FAA reports on this event · 1

The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.