Aircraft Accident/Incident Report

San Luis Obispo, California 93402
Tuesady, April 20, 1999 18:34 PDT

NTSB Narrative Summary Released at Completion of Accident

The pilot reported that he was about 6 miles northwest of the airport, returning to the airport for landing, the engine abruptly and completely ceased delivering power. The aircraft descended through a stratus cloud layer and broke out beneath a 900-foot ceiling. The pilot determined that the aircraft would not glide to the airport and made an emergency landing in an open field beside a highway. The right wing struck a sign during the landing. FAA inspectors reported that the engine fuel sump contained a clear fluid resembling water, and that the right-hand fuel tank sump drain had a threaded plug installed which precluded routine sampling of the tank for water.

NTSB Probable Cause Narrative

The inadequate preflight inspection of the aircraft by the pilot-in-command which resulted in a loss of engine power due to water contamination in the fuel system. A factor in the accident was an improper maintenance alteration which disabled a fuel sump drain.

Event Information

Type of Event Accident
Event Date 4/20/1999
Event Day of the Week Tuesday
Time of Event 1834
Event Time Zone Pacific Daylight Time
Event City SAN LUIS OBISPO
Event State CALIFORNIA
Event Country --
Zipcode of the event site 93402
Event Date Year 1999
Event Date Month 4
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 1856 Pacific Daylight Time
Direction of event from weather observation facility (degrees) 135
Weather Observation Facility ID SBP
Elevation of weather observation facility 209
Distance of event from weather observation facility (units?) 6
Time Zone of the weather observation PDT
Lighting Conditions Dusk
Lowest Ceiling Height 20000
Lowest Non-Ceiling Height 1300
Sky/Lowest/Cloud Conditions Scattered
Sky Condition for Lowest Ceiling Broken
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 15
Air Temperature at event time (in degrees celsius) 13
Dew Point at event time (in degress fahrenheit) 9
Wind Direction (degrees magnetic) 310
Variable Wind Indicator Unknown
Wind Speed (knots) 19
Wind Velocity Indicator Unknown
Wind Gust Indicator Unknown
Wind Gust (knots) 27
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) --
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) 444
NTSB Notification Source --
NTSB Notification Date Apr 20 1999 12:00AM
NTSB Notification Time 1900
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 12 2000 11:30AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N7317X
NTSB Number LAX99LA159
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 R182
Aircraft Series Identifier R182
Aircraft Serial Number R18200073
Certified Max Gross Weight 3112
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 Retractable
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Feb 3 1998 12:00AM
Airframe hours since last inspection 12
Airframe Hours 1607
ELT Installed Yes
ELT Activated Yes
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name LYNN D. MAHIN
Aircraft Owner Street Address 2265 GLENN ST.
Aircraft Owner City LOS OSOS
Aircraft Owner State CA
Aircraft Owner Country
Aircraft Owner Zipcode 93402
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 Yes
Departure Airport Code SBP
Departure City
Departure State CA
Departure Country
Departure Time 1800
Departure Time Zone PDT
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 Descent
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 --