Aircraft Accident/Incident Report

Wasilla, Alaska 99687
Saturday, May 16, 2009 11:40 AKD

NTSB Narrative Summary Released at Completion of Accident

The private pilot was on a Title 14, CFR Part 91, local area personal flight when the accident occurred. As he approached his destination airport he applied full carburetor heat, which resulted in a loss of engine power. After completing emergency engine procedures he was unable to restore engine power, and selected a shallow lake as a forced landing site. The airplane sustained substantial damage to the fuselage during the forced landing. The pilot reported that while the airplane was being disassembled after recovery, his mechanic removed the lower engine cowling, and discovered a worn, 4 inch by 2 inch portion of rubberized baffling material lodged inside of the carburetor air box assembly. An NTSB investigator traced the origin of the baffling to a worn, frayed, and torn section of engine cowling baffling adjacent to the carburetor heat fresh air inlet duct. The pilot/owner of the airplane reported that he was aware of the worn, frayed and torn engine baffling, and he planned to have it replaced at the airplaneā€™s next annual inspection. Given the discovery of the baffling material inside the carburetor air box, it is likely that once carburetor heat was applied, airflow pulled the baffling material into the carburetor inlet, restricting airflow to the carburetor with the resultant loss of power.

NTSB Probable Cause Narrative

A loss of engine power due to the blockage of the carburetor air inlet by a piece of engine baffling. Contributing to the accident was a worn engine baffle, and the pilot/owner's failure to have the engine baffle replaced.

Event Information

Type of Event Accident
Event Date 5/16/2009
Event Day of the Week Saturday
Time of Event 1140
Event Time Zone --
Event City Wasilla
Event State ALASKA
Event Country --
Zipcode of the event site 99687
Event Date Year 2009
Event Date Month 5
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude 613417N
Event Location Longitude 1492813W
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 --
Investigator's weather source Weather Observation Facility
Time of the weather observation 1156 Atlantic Daylight Time
Direction of event from weather observation facility (degrees) 90
Weather Observation Facility ID IYS
Elevation of weather observation facility 354
Distance of event from weather observation facility (units?) 6
Time Zone of the weather observation ADT
Lighting Conditions Day
Lowest Ceiling Height --
Lowest Non-Ceiling Height 4900
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) 12
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 --
Wind Gust (knots) --
Altimeter Setting at event time (in. Hg) 30.01
Density Altitude (feet) --
Intensity of Precipitation --
METAR weather report --
Event Highest Injury None
On Ground, Fatal Injuries --
On Ground, Minor Injuries --
On Ground, Serious Injuries --
Injury Total Fatal --
Injury Total Minor --
Injury Total None 1
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 26736
NTSB Notification Source ANC FAA, ROC
NTSB Notification Date --
NTSB Notification Time --
Fiche Number and/or location -used to find docket information --
Date of most recent change to record Apr 16 2010 3:35PM
User who most recently changed record johb
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N7440P
NTSB Number ANC09LA042
Missing Aircraft Indicator --
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? No
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name PIPER
Aircraft Model PA-24-250
Aircraft Series Identifier --
Aircraft Serial Number 24-2629
Certified Max Gross Weight 2900
Aircraft Category Airplane
Aircraft Registration Class --
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 Aug 13 2008 12:00AM
Airframe hours since last inspection 32
Airframe Hours 3347
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type C91
Aircraft Owner Name BRUCE W. CHRISTIE
Aircraft Owner Street Address --
Aircraft Owner City WASILLA
Aircraft Owner State AK
Aircraft Owner Country USA
Aircraft Owner Zipcode 99654-4355
Operator is an individual? No
Operator Name BRUCE W. CHRISTIE
Operator Same as Owner? Yes
Operator Is Doing Business As --
Operator Address Same as Owner? Yes
Operator Street Address --
Operator City WASILLA
Operator State AK
Operator Country USA
Operator Zip code 99654-4355
Operator Code --
Owner has at least one certificate None
Other Operator of large aircraft? No
Certified for Part 133 or 137 Operation --
Operator Certificate Number --
Indicates whether an air carrier operation was scheduled or not Non-scheduled
Indicates Domestic or International Flight Domestic
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 PAWS
Departure City Wasilla
Departure State AK
Departure Country USA
Departure Time 1040
Departure Time Zone ADT
Destination Same as Local Flt --
Destination Airport Code 0AK1
Destination City Wasilla
Destination State AK
Destination Country USA
Specific Phase of Flight --
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Mar 29 2010 2:46PM
User who most recently changed record stam
Since inspection or accident Time of Accident
Event Location Runway Number and Location N/A
Runway Length --
Runway Width --
Sight Seeing flight No
Air Medical Flight No
Medical Flight --