ANC95LA111

NTSB accident investigation · Piper PA-12 · Anchorage, AK · July 21, 1995

Accident · Serious injuriesLimited investigationFinal report
Date
July 21, 1995, 15:55 local (23:55 UTC)
Place
Anchorage, AK
Injuries
1 serious, 1 minor
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N7755HPiper PA-12
Weather
Visual (VMC) · Day
Status
Completed · report February 27, 1996
Report
Approved by Office Director
NTSB office
Alaska Regional Office
FAA report
19950721019419A
Case key
2692

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 improper use of carburetor heat which led to carburetor icing and a partial loss of engine power. Factors contributing to the accident are prevailing carburetor icing conditions, and the pilot's failure to properly judge the airplane's distance and speed during the forced landing.

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) - nonmechanicalClimb
Weather condition - carburetor icing conditionsFactor
Fuel system,carburetor - iceCause
Carburetor heat - improper use ofPilot in commandCause
Forced landingEmergency descent/landing
Loss of control - on ground/waterEmergency descent/landing
Distance/speed - misjudgedPilot in commandFactor
Stall/mush - encounteredPilot in command

Analysis

The pilot departed from the private airstrip after a successful engine run-up. During the climb, at about 700 feet above the ground, the engine lost partial power. The pilot attempted a forced landing but misjudged his approach and the airplane stalled as he overshot the FAR end of the runway. The airplane impacted terrain and was substantially damaged. The accident flight was the airplane's first flight after the engine had been rebuilt. A detailed examination of the engine and fuel system did not reveal evidence of malfunction. According FAA carburetor icing probability charts, the prevailing weather conditions at the time of the accident could produce 'serious' carburetor icing at cruise power. The pilot stated that he applied carburetor heat at the time of the loss of power, with no effect.

Factual narrative

On July 21, 1995, about 1555 Alaska daylight time, N7755H, a Piper PA-12, collided with terrain during a forced landing in Anchorage and was substantially damaged. The forced landing was precipitated by a partial loss of engine power while the airplane was maneuvering. The private pilot received minor injuries and the sole passenger received serious injuries. Visual meteorological conditions prevailed and no flight plan had been filed. The personal flight was conducted under 14 CFR 91.

The pilot stated that the accident flight was the first flight since the engine was rebuilt. After a preflight inspection and successful engine run-up, the airplane departed from a private airstrip and maneuvered about 700 feet above the airstrip. The pilot reported that the "engine lost power," but did not stop. The pilot immediately descended and maneuvered to approach the airstrip and land to the north. He overshot the landing strip and purposely stalled the airplane in an effort to avoid colliding with obstructions. The airplane impacted terrain about 200 feet beyond the end of the runway and was substantially damaged.

An examination of the engine and fuel system did not reveal evidence of any mechanical deficiencies. The reported temperature and dew point near the time and place of the accident were 59 degrees F and 57 degrees F respectively. According to the Carburetor Icing Probability Chart published by the FAA (attached), the prevailing weather conditions could produce "serious icing at cruise power" in light aircraft piston engines.

The pilot stated that he had applied full carburetor heat immediately upon sensing the power loss, with no effect noted. He said the airplane could not maintain altitude, but the engine continued to run.

Aircraft

Registration
N7755H
Reported as
Piper PA-12
Category
Airplane
Serial number
12-653
Airframe hours
2,344
Engine
Lycoming O-320-A2B, 160 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Operator
John F. Strong
Registered owner
Badura, Joseph H.
Airworthiness certificate
Standard, Normal
Last inspection
Annual · July 21, 1995 · 0 hours before
Airport
O'Mally Sky Harbor

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
70
Certificate
Private
Airplane ratings
Single-engine land, Multi-engine land, Single-engine sea
Medical
Class 3, Valid Medical--w/ waivers/lim
Seat
Front
Flight hours
10,000 total · 4,000 in this make and model · 7 in the last 90 days · 5 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
260° at 10 knots
Visibility
20 statute miles
Lowest ceiling
1,700 ft broken
Temperature
59 °F, dew point 57 °F
Altimeter
30.00 inHg
Observed at
ANC, 7 nm away

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 N7755H · 1

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