ANC95LA131

NTSB accident investigation · Piper PA-18-160 · Port Alsworth, AK · August 6, 1995

Accident · No injuriesLimited investigationFinal report
Date
August 5, 1995, 19:30 local (Aug 6, 1995, 03:30 UTC)
Place
Port Alsworth, AK
Injuries
2 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N814JMPiper PA-18-160
Weather
Visual (VMC) · Day
Status
Completed · report February 27, 1996
Report
Approved by Office Director
NTSB office
Alaska Regional Office
FAA report
19950805028659A
Case key
2710

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

An in-flight separation of a propeller blade, which resulted in a severe vibration, shutdown of the engine, and a forced landing in alder bushes.

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.

Propeller failure/malfunctionCruise
Propeller system/accessories - previous damage
Propeller system/accessories,blade - separationCause
Powerplant - vibration
Engine shutdown - performed
Forced landingEmergency descent/landing
In flight collision with terrain/waterEmergency landing
Terrain condition - high vegetation

Analysis

During cruise flight, approximately 9.5 inches of a propeller blade separated from the airplane's propeller, and the airplane began a severe vibration. The pilot closed the throttle and pulled the mixture to the idle cut off position. He then landed in alder bushes, and the airplane nosed over. Records showed that the propeller had sustained a previous propeller strike and that it had been straightened and cut to 80 inches.

Factual narrative

On August 5, 1995, at 1930 Alaska daylight time, a float equipped Piper PA-18-160 airplane, N814JM, registered to and operated by the pilot, lost 9.5 inches of a propeller blade and the pilot was forced to land the airplane approximately 15 miles northeast of Port Alsworth, Alaska. The personal flight, operating under 14 CFR Part 91, departed Port Alsworth for a local game spotting flight. No flight plan was filed and visual meteorological conditions prevailed. The commercial certificated pilot and the passenger were not injured and the airplane was substantially damaged.

According to the pilot, during cruise flight the engine began to vibrate severely. He closed the throttle and pulled the mixture to the idle cutoff position. He pushed the nose of the airplane toward the ground and landed in the alder bushes. The airplane nosed over. Examination of the airplane showed that 9.5 inches of one propeller blade was missing.

Examination of the airplane records showed that the propeller had been straightened on September 30, 1994. The pilot stated during a telephone conversation on August 7, 1995, that the propeller had sustained a "propeller strike." The copy of the yellow tag submitted by the pilot showed that as a result of the propeller strike and resulting blade tip damage, the propeller had to be straightened and cut to 80 inches. The pilot also had the blade pitch angle changed to 45 inches.

The pilot did not submit the propeller for examination as requested.

Aircraft

Registration
N814JM
Reported as
Piper PA-18-160
Category
Airplane
Serial number
18-8608
Airframe hours
3,820
Engine
Lycoming O-320-B2B, 160 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Registered owner
Jeremy Davis
Airworthiness certificate
Standard, Normal
Last inspection
Annual · June 16, 1995 · 220 hours before
Departed
AK

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
Multi-engine land, Single-engine sea, Single-engine land
Instrument ratings
Airplane
Medical
Class 2, Valid Medical--w/ waivers/lim
Seat
Front
Flight hours
2,625 total · 850 in this make and model · 2,300 as pilot in command · 250 in the last 90 days · 100 in the last 30 days · 3 in the last 24 hours

Weather

Conditions
Visual (VMC) · Day
Visibility
30 statute miles
Lowest ceiling
5,500 ft broken
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 N814JM · 1

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