Aircraft Accident/Incident Report

Castle Rock, Colorado 80104
Sunday, August 3, 1997 10:30 MDT

NTSB Narrative Summary Released at Completion of Accident

While in cruise flight, engine RPMs dropped from 2,350 to 1,700, and the airplane began to descend. The pilot made a forced landing in an open, uneven field. The landing gear was sheared off and the fuselage was buckled. Postaccident examination of the engine disclosed the no. 4 cylinder exhaust valve was jammed in the open position. The valve stem and guide were coated with 'gummy black deposits.' The pilot had a similar accident on July 22, 1995 (FTW 95-L-A312). In that accident, the jammed exhaust valve was attributed to excessive carbon deposits from high octane aviation gasoline usage in a low compression engine.

NTSB Probable Cause Narrative

A partial loss of engine power due to a cylinder exhaust valve jammed in the open position from excessive carbon deposits. A factor was the lack of suitable terrain on which to make a forced landing.

Event Information

Type of Event Accident
Event Date 8/3/1997
Event Day of the Week Sunday
Time of Event 1030
Event Time Zone Mountain Daylight Time
Event City CASTLE ROCK
Event State COLORADO
Event Country --
Zipcode of the event site 80104
Event Date Year 1997
Event Date Month 8
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 Not pertinent
Investigator's weather source Weather Observation Facility
Time of the weather observation 945 Mountain Daylight Time
Direction of event from weather observation facility (degrees) 348
Weather Observation Facility ID APA
Elevation of weather observation facility 5883
Distance of event from weather observation facility (units?) 16
Time Zone of the weather observation MDT
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 20000
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 50
Air Temperature at event time (in degrees celsius) 25
Dew Point at event time (in degress fahrenheit) 14
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 30
Density Altitude (feet) 7800
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal --
Injury Total Minor --
Injury Total None 1
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 445
NTSB Notification Source --
NTSB Notification Date --
NTSB Notification Time 0
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 8 2000 12:29PM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N5985V
NTSB Number FTW97LA298
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed Unknown
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Piper
Aircraft Model J3C-65
Aircraft Series Identifier J3C-65
Aircraft Serial Number 13-640
Certified Max Gross Weight 1220
Aircraft Category Airplane
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? Unknown
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 Dec 1 1996 12:00AM
Airframe hours since last inspection 44
Airframe Hours 4954
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name DONALD L. BREHM
Aircraft Owner Street Address 6518 S. GARLAND WAY
Aircraft Owner City LITTLETON
Aircraft Owner State CO
Aircraft Owner Country
Aircraft Owner Zipcode 80123
Operator is an individual? --
Operator Name
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address
Operator City
Operator State
Operator Country
Operator Zip code
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 No
Departure Airport Code APA
Departure City ENGLEWOOD
Departure State CO
Departure Country
Departure Time 1000
Departure Time Zone MDT
Destination Same as Local Flt dest & departure same, accident can occur anywhere
Destination Airport Code
Destination City
Destination State
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 --