CHI08CA280

NTSB accident investigation · Cessna 150G · Urbana, OH · September 10, 2008

Accident · Minor injuriesData collectionFinal report
Date
September 10, 2008, 10:30 local (14:30 UTC)
Place
Urbana, OH
Injuries
1 minor, 1 uninjured
Damage
Substantial damage
Phase of flight
Approach
Aircraft
N3899JCessna 150G
Defining event
Approach-VFR pattern base: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed · report March 23, 2009
Report
Approved by Office Director
Parties
Federal Aviation Administration - Columbus FSDO
FAA report
20080910846169A
Case key
69038

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

A loss of engine power due to carburetor ice. Contributing to the accident were environmental conditions conducive to carburetor icing.

Findings · 2

NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.

Temp/humidity/pressure: conducive to carburetor icingEnvironmental issues › Conditions/weather/phenomena · Effect on equipmentCessna 150G: 4 casesAll aircraft: 435 casesProbable cause
Temp/humidity/pressureEnvironmental issues › Conditions/weather/phenomena · Not specifiedCessna 150G: 1 caseAll aircraft: 7 casesProbable cause

Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.

Analysis

The pilot reported that as she approached the destination airport after a 1-hour cross-country flight, she reduced engine power to approximately 2,300 rpm in order to descend to traffic pattern altitude. During the downwind leg, she further reduced engine power to 2,000 rpm to slow the airplane to for the approach. As she initiated a turn to base leg, she made a final reduction of engine power and activated the carburetor heat. During the turn to base leg, the engine began to lose power. The loss of engine power was reported to be gradual, not instantaneous, occurring over a period of approximately 5 seconds. The engine did not respond to throttle and mixture control movements. The pilot stated that the loss of engine power occurred 700-800 feet above ground level while on base leg. She said that she was worried about stalling the airplane and established a descent to remain above stall speed. The airplane landed in a grassy area about 50 feet short of the runway. Shortly after touchdown the nose gear collapsed and the airplane came to an abrupt stop. The temperature and dew point in the vicinity of the accident site were 17 degrees and 12 degrees Celsius, respectively. Calculations using a carburator icing chart indicate the possibility of moderate carburetor icing at cruise power and serious icing at descent power under the indicated conditions.

Factual narrative

The pilot reported that she departed on the 1-hour cross country flight with 26 gallons of fuel on board. The pilot said that her cruise altitude varied between 2,500 and 3,000 feet mean sea level (msl). As the airplane approached the destination airport, she reduced engine power to approximately 2,300 rpm in order to descend to traffic pattern altitude. During the downwind leg, a reduction of engine power to 2,000 rpm was made to slow the airplane to approach airspeed. As she initiated a turn to base leg, a final reduction of engine power was made and the carburetor heat was activated. During the turn to base leg, the engine began to lose engine power. The loss of engine power was reported to be gradual, not instantaneous, occurring over a period of approximately 5 seconds. The engine did not respond to throttle and mixture control movements. The pilot stated that the loss of engine power occurred 700-800 feet above ground level (agl) while on base leg. She said that she was worried about stalling the airplane, and established a descent to remain above stall speed. The airplane landed in a grass area about 50 feet short of the runway. Shortly after touchdown the nose gear collapsed and the airplane came to an abrupt stop. The temperature and dew point in the vicinity of the accident site were 17 degrees and 12 degrees Celsius, respectively. Data indicated the possibility of moderate carburetor icing at cruise power and serious icing at descent power under those conditions.

Aircraft

Registration
N3899J
Reported as
Cessna 150G
Category
Airplane
Serial number
15065199
Airframe hours
11,955
Engine
Teledyne Continental Motors O-200-A, 100 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Airworthiness certificate
Standard, Utility
Last inspection
Annual · November 30, 2007
Departed
K3G4 · Ashland, OH
Destination
KI74 · Urbana, OH
Airport
KI74 · Grimes Field Airport, runway 20, 4,400 × 100 ft, asphalt

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
69
Injuries
Minor
Certificate
Commercial
Airplane ratings
Single-engine land
Instrument ratings
Airplane
Medical
Class 2, With waivers/limitations
Last flight review
May 17, 2007
Seat
Left
Flight hours
1,913 total · 455 in this make and model

Weather

Conditions
Visual (VMC) · Day
Wind
45° at 2 knots, gusting 4
Visibility
10 statute miles
Lowest ceiling
None
Temperature
63 °F, dew point 54 °F
Altimeter
30.29 inHg
Observed at
OH19, 6 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.