ERA16LA300

NTSB accident investigation · Cessna 150 · Littleton, MA · August 19, 2016

Accident · No injuriesLimited investigationFinal report
Date
August 19, 2016, 13:49 local (17:49 UTC)
Place
Littleton, MA
Injuries
1 uninjured
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N9230UCessna 150
Defining event
Enroute-cruise: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed · report November 15, 2018
Report
Approved by Office Director
NTSB office
Eastern Region Aviation
Parties
FAA/FSDO
FAA report
20160819024279A
Case key
93901

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

A total loss of engine power during descent for reasons that could not be determined because postaccident examination of the airframe and engine revealed no anomalies that would have precluded normal operation.

Findings · 1

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.

Not determinedNot determined › Not determined · Unknown/Not determinedCessna 150M: 8 casesAll aircraft: 2,247 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 student pilot was conducting a solo cross-country flight and filled the airplane's fuel tanks before departing on the first leg of the flight. While descending from 4,500 ft mean sea level approaching the destination airport, engine power decreased from 2,500 to 1,300 rpm. The student advanced the mixture to full rich and applied carburetor heat; however, there was no change in engine performance. Soon after, the engine experienced a total loss of power and the student performed a forced landing to a field. About 10 gallons of fuel were drained from the airplane during recovery. Examination of the airframe and engine did not reveal any evidence of preaccident mechanical malfunction or abnormalities. A review of a carburetor icing chart revealed that the atmospheric conditions at the time of the accident were conducive to icing at glide and cruise power; however, since engine performance did not improve after the application of carburetor heat, it is unlikely that the loss of engine power was the result of carburetor ice.

Factual narrative

On August 19, 2016, at 1349 eastern daylight time, a Cessna 150M, N9230U, was substantially damaged when it impacted trees and terrain during a forced landing near Littleton, Massachusetts. The student pilot was not injured. Visual meteorological conditions prevailed, and no flight plan was filed for the solo instructional flight that was operated under the provisions of Title 14 Code of Federal Regulations Part 91. The flight departed from Sanford Seacoast Regional Airport (SFM), Sanford, Maine, with the intended destination of Minute Man Air Field (6B6), Stow, Massachusetts.According to the student pilot, he was on a solo cross-country flight and topped-off the fuel tanks with 100 low lead aviation fuel prior to departing on the first leg of the flight. He departed 6B6, landed at Laconia Municipal Airport (LCI), Laconia, New Hampshire, and then continued to SFM. After departing SFM, while in a cruise descent from 4,500 feet mean sea level (msl) on a 4 mile straight-in approach to runway 21 to 6B6, the engine lost partial power when the rpm decreased from 2,500 to 1,300 rpm around 2,500 feet msl. The student thought he could make it to the runway, but then began searching for a field to perform a forced landing. He located a field, turned toward it, and then began troubleshooting the engine. The student pilot advanced the mixture to full rich and applied carburetor heat; however, there was no change in the engine performance. As he was about to turn onto the final leg of the traffic pattern to the field, about 800 feet msl, the engine lost total power. The pilot landed the airplane in the selected field, which was about 300 feet msl, it impacted a stone wall and trees, and then came to rest in the upright position. According to the flight instructor, the student pilot received his student pilot certificate in September 2014. His most recent third-class medical certificate was issued on September 18, 2014. At the time of the accident, he had accumulated 73 hours of total flight time, of which 51 hours were in the same make and model as the accident airplane and 11 hours were as pilot-in-command. According to Federal Aviation Administration records, the airplane was manufactured in 1976, issued an airworthiness certificate in May 2015, and was registered a flight school. In addition, it was equipped with a Lycoming O-200 series, 100-horsepower engine. According to the flight instructor, a 100-hour inspection was performed on the airplane August 4, 2016, at a total time of 8,216.4 hours, and a tach time of 969 hours. At the time of the accident, the tachometer indicated 986.8 hours. Examination of the airplane revealed that both wings were partially separated from the fuselage and the leading edges were impact damaged. The engine was examined and fuel was noted in the carburetor bowl. The fuel was free of water and debris. The rocker arm covers were removed and no anomalies were noted. Crankshaft and valve train continuity was confirmed from thepropeller to the accessory section of the engine by rotating the propeller. In addition, evidence of compression was observed on all cylinders. The magnetos produced spark on all towers, the spark plugs exhibited normal wear, and were in "new condition." During the recovery, about 10 gallons of fuel were drained from the airplane. The reported weather around the time of the accident at Laurence G Hanscom Field (BED), Bedford, Massachusetts, which was located 10 miles east of the accident location, indicated wind from 330° at 4 knots, 10 miles visibility, few clouds at 6,000 feet above ground level (agl), temperature 31° C, dew point 13° C, and an altimeter setting of 29.90 inches of mercury. The carburetor icing probability chart from Federal Aviation Administration (FAA) Special Airworthiness Information Bulletin (SAIB): CE-09-35 Carburetor Icing Prevention, June 30, 2009, shows a probability of icing at glide and cruise power at the temperature and dew point reported at the time of the accident. According to the NTSB Pilot/Operator Report that was filed by the flight instructor, under the mechanical malfunction/failure section of the report it stated that the "engine fail[ed] due to carb[uretor] ice."

Aircraft

Registration
N9230U
Reported as
Cessna 150 (M)
Category
Airplane
Serial number
15078180
Built
1976
Airframe hours
8,216.4
Engine
Cont Motor O-200-A-48, 100 horsepower, reciprocating
Damage
Substantial damage
Flight
Instructional · Part 91
Operator
Aptis Aviation
Registered owner
Aptis Aviation
Airworthiness certificate
Standard, Normal; Standard, Utility
Last inspection
Annual · August 4, 2016 · 18 hours before
Departed
SFM · Sanford, ME
Destination
6B6 · Stow, MA
Flight plan
VFR
Airport
6B6 · Minute Man Air Field
Equipment
Stall warning system

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
18
Injuries
None
Certificate
Student
Medical
Class 3, Without waivers/limitations
Seat
Left
Restraint
3-point
Flight hours
73.5 total · 50.9 in this make and model · 11.3 as pilot in command · 5.5 in the last 90 days · 5.5 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
330° at 4 knots
Visibility
10 statute miles
Lowest ceiling
None
Temperature
88 °F, dew point 55 °F
Altimeter
29.89 inHg
Observed at
BED, 10 nm away

Docket · 7

The files NTSB released with the investigation on August 27, 2018, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.1 MB in all.

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 N9230U · 1

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