Aircraft Accident/Incident Report

Herron, Washington 98349
Sunday, February 29, 2004 16:25 PST

NTSB Narrative Summary Released at Completion of Accident

The airplane was en route when according to the last nine minutes of radar data, the airplane descended from 3,400 to 300 feet. Sixteen days after the aircraft was reported missing Search and Rescue personnel located the airplane in a water inlet at a depth of 132 feet; 19 days later the aircraft was recovered from the accident site. A postaccident examination of the engine and the airframe revealed that the left exhaust muffler had separated at the forward seam, with evidence of sooting noted on the scat hoses surrounding the area. It was also observed that the forward end cap and exhaust riser were separated from the main body of the muffler. Magnified examinations found that almost all of the fractures were blackened and severely oxidized. The failure of the muffler was the result of undetected oxidation and cracking resulting from normal thermal degradation. The cracking would have allowed exhaust gases direct access to cabin air through the heater system. Toxicological testing of the pilot and his passenger revealed carbon monoxide levels of 45 percent and 46 percent, respectively.

NTSB Probable Cause Narrative

The failure of the left muffler while maneuvering, resulting in a carbon monoxide leak into the cabin rendering the pilot incapacitated, and the subsequent uncontrolled descent and impact with water.

Event Information

Type of Event Accident
Event Date 2/29/2004
Event Day of the Week Sunday
Time of Event 1625
Event Time Zone Pacific Standard Time
Event City Herron
Event State WASHINGTON
Event Country --
Zipcode of the event site 98349
Event Date Year 2004
Event Date Month 2
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 471650N
Event Location Longitude 1224949W
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 Unknown
Time of the weather observation 1635 Pacific Standard Time
Direction of event from weather observation facility (degrees) 10
Weather Observation Facility ID PWT
Elevation of weather observation facility 439
Distance of event from weather observation facility (units?) 13
Time Zone of the weather observation PST
Lighting Conditions Day
Lowest Ceiling Height --
Lowest Non-Ceiling Height 8000
Sky/Lowest/Cloud Conditions Few
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) --
Visibility Runway Visual Value (Statute Miles) --
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) 9
Dew Point at event time (in degress fahrenheit) 2
Wind Direction (degrees magnetic) --
Variable Wind Indicator --
Wind Speed (knots) --
Wind Velocity Indicator Calm
Wind Gust Indicator Not Gusting
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 30
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury Fatal
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal 2
Injury Total Minor --
Injury Total None --
Injury Total Serious --
Injury Total All 2
Investigating Agency NTSB
NTSB Docket Number (internal use) 18042
NTSB Notification Source FAA Regional Operations Center
NTSB Notification Date Mar 1 2004 12:00AM
NTSB Notification Time 600
Fiche Number and/or location -used to find docket information DMS
Date of most recent change to record Jul 7 2005 10:33AM
User who most recently changed record NTSB\JOHB
Basic weather conditions Visual Meteorological Cond
FAA District Office Seattle, Washington

Aircraft Involved

Aircraft #1

Aircraft Registration Number N2534V
NTSB Number SEA04LA050
Missing Aircraft Indicator Y
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? No
Damage Destroyed
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Cessna
Aircraft Model 170
Aircraft Series Identifier --
Aircraft Serial Number 18038
Certified Max Gross Weight 2200
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 4
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Sep 13 2003 12:00AM
Airframe hours since last inspection 8.7
Airframe Hours 3847.1
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name David W. Verstrate
Aircraft Owner Street Address --
Aircraft Owner City Federal Way
Aircraft Owner State WA
Aircraft Owner Country USA
Aircraft Owner Zipcode 980923
Operator is an individual? No
Operator Name --
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? No
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? --
Certified for Part 133 or 137 Operation --
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 2WA1
Departure City Sequim
Departure State WA
Departure Country USA
Departure Time 1545
Departure Time Zone PST
Destination Same as Local Flt --
Destination Airport Code S50
Destination City Auburn
Destination State WA
Destination Country USA
Specific Phase of Flight Descent
Report sent to ICAO? No
Evacuation occurred No
Date of most recent change to record Apr 28 2005 4:19PM
User who most recently changed record STAM
Since inspection or accident Time of Accident
Event Location Runway Number and Location NA
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --