Aircraft Accident/Incident Report

Miami, Florida 33109
Sunday, October 19, 1997 10:30 EDT

NTSB Narrative Summary Released at Completion of Accident

About 10 minutes into the flight, at a cruise altitude of 1000 feet, the pilot experienced a loss of engine power. He radioed a 'mayday' call and selected a nearby golf course for an emergency landing. The airplane collided with a palm tree during the emergency landing roll. Examination of the engine assembly revealed that number one cylinder lower spark plug was partially separated from the cylinder. During the subsequent engine teardown, the number one exhaust valve head was recovered from inside the cylinder. The examination also of the exhaust valve stem and the and the valve stem keepers showed excessive wear. The valve stem keepers had also separated from their normally installed positions. A review of the aircraft maintenance logs disclosed that the engine had undergone several major engine repairs, involving the valve assemblies, within the last ten years. An engine top overhaul was completed 370 hours before this accident. The engine had accumulated a total of 5,603 hours.

NTSB Probable Cause Narrative

excessive wear to the number one valve stem and valve stem keepers that resulted in the separation of the valve assembly.

Event Information

Type of Event Accident
Event Date 10/19/1997
Event Day of the Week Sunday
Time of Event 1030
Event Time Zone Eastern Daylight Time
Event City MIAMI
Event State FLORIDA
Event Country --
Zipcode of the event site 33109
Event Date Year 1997
Event Date Month 10
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport
Event Location Nearest Airport ID
Indicates whether the acc/inc occurred off or on an airport Off Airport/Airstrip
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness Full
Investigator's weather source Weather Observation Facility
Time of the weather observation 950 Eastern Standard Time
Direction of event from weather observation facility (degrees) 320
Weather Observation Facility ID MIA
Elevation of weather observation facility 11
Distance of event from weather observation facility (units?) 20
Time Zone of the weather observation EST
Lighting Conditions Day
Lowest Ceiling Height 15000
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Unknown
Sky Condition for Lowest Ceiling Broken
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 24
Dew Point at event time (in degress fahrenheit) 15
Wind Direction (degrees magnetic) 340
Variable Wind Indicator Unknown
Wind Speed (knots) 8
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) 1700
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury Minor
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor 1
Injury Total None 1
Injury Total Serious --
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 1171
NTSB Notification Source --
NTSB Notification Date Oct 19 1997 12:00AM
NTSB Notification Time 1135
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 8 2000 12:36PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N7814U
NTSB Number ATL98LA003
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Cessna
Aircraft Model 150M
Aircraft Series Identifier 150M
Aircraft Serial Number 150-77847
Certified Max Gross Weight 1600
Aircraft Category Airplane
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? No
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft 2
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Mar 4 1997 12:00AM
Airframe hours since last inspection 90
Airframe Hours 5603
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name N718U
Aircraft Owner Street Address 6301 SW 6TH STREET
Aircraft Owner City PEMBROKE PINE
Aircraft Owner State FL
Aircraft Owner Country
Aircraft Owner Zipcode
Operator is an individual? --
Operator Name WILLIAM B. TINKHAM
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address 847 NE 119TH STREET
Operator City MIAMI
Operator State FL
Operator Country
Operator Zip code 33161
Operator Code
Owner has at least one certificate None
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation Unknown
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not --
Indicates Domestic or International Flight --
Operator carrying Pax/Cargo/Mail --
Type of Flying (Per_Bus / Primary) Personal
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code HWO
Departure City
Departure State FL
Departure Country
Departure Time 1020
Departure Time Zone EDT
Destination Same as Local Flt --
Destination Airport Code MTH
Destination City MARATHON
Destination State FL
Destination Country
Specific Phase of Flight Cruise
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Jan 2 2001 10:34AM
User who most recently changed record dbo
Since inspection or accident --
Event Location Runway Number and Location 0
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --