NYC08LA137

NTSB accident investigation · Cessna 150F · Middlesboro, KY · March 13, 2008

Accident · Serious injuriesLimited investigationFinal report
Date
March 13, 2008, 15:20 local (19:20 UTC)
Place
Middlesboro, KY
Injuries
1 serious
Damage
Substantial damage
Phase of flight
Enroute
Aircraft
N6651FCessna 150F
Defining event
Enroute-cruise: Loss of engine power (total)
Weather
Visual (VMC) · Day
Status
Completed · report November 25, 2008
Report
Approved by Office Director
Parties
FAA/FSDO
FAA report
20080313012699A
Case key
67664

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

The mechanic's improper maintenance installation of the No. 1 cylinder rocker arms which led to oil starvation and a loss of engine power.

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.

Maintenance: installationPersonnel issues › Task performance · Maintenance personnelCessna 150F: 2 casesAll aircraft: 371 casesProbable cause
Engine (reciprocating): recip eng cyl sectionAircraft › Aircraft power plant · Incorrect service/maintenanceCessna 150F: 3 casesAll aircraft: 373 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

During a period of 6 months, a major engine overhaul and annual inspection was being performed on the pilot's airplane. The work was being performed by the pilot's friend, who was an airframe and powerplant mechanic with an inspector authorization. The accident flight was the first flight after the work was completed. About 10 minutes after departure, the engine began vibrating and lost all power during cruise flight. The major overhaul had included the installation of new cylinders. Proper installation of the new cylinders required that the exhaust valve rocker arms have a small orifice to allow oil to pass and lubricate the valves. The intake valve rocker arms did not have an orifice. Examination of the accident engine revealed that the No. 1 cylinder intake valve was stuck open, and exhibited features consistent with oil starvation. Further examination revealed that the No. 1 cylinder had an intake rocker arm (no orifices) on both the intake and exhaust valves. The No. 3 cylinder had an exhaust valve rocker arm (with orifice) on both the intake and exhaust valves. Review of a make and model engine overhaul manual revealed a caution, noting that the exhaust valve rocker arms have an orifice. Further examination of the cylinder did not reveal any additional mechanical anomalies.

Factual narrative

On March 13, 2008, about 1520 eastern daylight time, a Cessna 150F, N6651F, was substantially damaged during a forced landing, following a total loss of engine power in cruise flight near Middlesboro, Kentucky. The certificated commercial pilot was seriously injured. No flight plan was filed for the personal flight conducted under 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed for the flight that departed Middlesboro-Bell County Airport (1A6), Middlesboro, Kentucky; destined for Pike County Airport (PBX), Pikeville, Kentucky.

The pilot owned and operated the airplane. He stated that the airplane was based at PBX, but had been at 1A6 for about 6 months, while undergoing a major engine overhaul and annual inspection. The work was being performed by the pilot's friend, who was an airframe and powerplant mechanic with an inspector authorization. The accident flight was the first flight after the work was completed.

The pilot was attempting to ferry the airplane back to PBX. About 10 minutes after departure, the engine began vibrating and lost all power during cruise flight. The pilot attempted a forced landing; however, the airplane struck utility wires. The airplane then pitched up, descended inverted, and impacted the ground.

The airplane was equipped with a Teledyne Continental Motors (TCM) O-200, 100-horsepower engine. The major overhaul included the installation of Airmotive Engineering Corporation (AEC) cylinders. According to a Federal Aviation Administration (FAA) inspector, the exhaust valve rocker arms, for cylinders on that model engine, had a small orifice to allow oil to pass and lubricate the valves. The intake valve rocker arms did not have an orifice. Examination of the accident engine by the FAA inspector revealed that the No. 1 cylinder intake valve was stuck open, and exhibited features consistent with oil starvation. Further examination revealed that the No. 1 cylinder had an intake rocker arm (no orifices) on both the intake and exhaust valves. The No. 3 cylinder had an exhaust valve rocker arm (with orifice) on both the intake and exhaust valves.

Review of a TCM overhaul manual for the O-200 model engine revealed, "CAUTION...Exhaust rocker has an oil orifice in the valve stem end for valve stem lubrication."

Further examination of the No. 1 cylinder, at the cylinder manufacturer, under the supervision of an FAA inspector, did not reveal any additional mechanical anomalies with the cylinder.

The reported weather at K1A6, at 1515, was: wind from 180 degrees at 15 knots, gusting to 19 knots; visibility 10 miles; scattered clouds at 9,000 feet; temperature 22 degrees Celsius (C); dew point 4 degrees C; altimeter 29.86 inches of mercury.

Aircraft

Registration
N6651F
Reported as
Cessna 150F
Category
Airplane
Serial number
15063251
Airframe hours
4,029
Engine
Continental O-200, 100 horsepower, reciprocating
Damage
Substantial damage
Flight
Personal · Part 91
Registered owner
Emory C Hurley
Airworthiness certificate
Standard, Utility
Last inspection
Annual · March 1, 2008
Departed
1A6 · Middlesboro, KY
Destination
PBX · Pikeville, KY
Airport
1A6 · Middlesboro-Bell County

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
65
Injuries
Serious
Certificate
Commercial
Airplane ratings
Multi-engine land, Single-engine sea, Single-engine land
Instrument ratings
Airplane
Medical
Class 3, Unknown
Last flight review
October 1, 2007
Seat
Left
Flight hours
742 total · 72 in this make and model · 742 as pilot in command · 5 in the last 90 days · 1 in the last 30 days

Weather

Conditions
Visual (VMC) · Day
Wind
180° at 15 knots, gusting 19
Visibility
10 statute miles
Lowest ceiling
None
Temperature
72 °F, dew point 39 °F
Altimeter
29.86 inHg
Observed at
1A6

FAA reports on this event · 1

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