Sleeper Strip Airport
Aircraft Accident/Incident Report

Anchorage, Alaska 99503
Monday, March 28, 1994 14:20 AKD

NTSB Narrative Summary Released at Completion of Accident

WHILE IN CRUISE FLIGHT ENGINE SUDDENLY BEGAN TO RUN ROUGH AND LOOSE POWER. NO UNUSUAL NOISE WAS ASSOCIATED WITH THE ANOMALY. EXAMINATION OF THE ENGINE REVEALED DAMAGE TO THE UPPER SURFACE OF THE NO. 4 PISTON. THE DAMAGE TO THE PISTON WAS CONSISTENT WITH DETONATION AND SUBSEQUENT RING BREAKAGE.

NTSB Probable Cause Narrative

THE PARTIAL FAILURE OF THE NO. 4 PISTON FROM OVER TEMPERATURE (DETONATION).

Event Information

Type of Event Incident
Event Date 3/28/1994
Event Day of the Week Monday
Time of Event 1420
Event Time Zone --
Event City ANCHORAGE
Event State ALASKA
Event Country --
Zipcode of the event site 99503
Event Date Year 1994
Event Date Month 3
MidAir Collision Indicator No
On Ground Collision occurred ? No
Event Location Latitude
Event Location Longitude
Event Location Airport SLEEPER STRIP
Event Location Nearest Airport ID
Indicates whether the acc/inc occurred off or on an airport On Airport
Distance from airport in statute miles --
Degrees magnetic from airport --
Airport Elevation --
Weather Briefing Completeness Not pertinent
Investigator's weather source Pilot
Time of the weather observation 0
Direction of event from weather observation facility (degrees) 0
Weather Observation Facility ID
Elevation of weather observation facility 0
Distance of event from weather observation facility (units?) 0
Time Zone of the weather observation
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 20000
Sky/Lowest/Cloud Conditions Thin Broken
Sky Condition for Lowest Ceiling Unknown
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) 6
Dew Point at event time (in degress fahrenheit) -4
Wind Direction (degrees magnetic) 270
Variable Wind Indicator Unknown
Wind Speed (knots) 5
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 29
Density Altitude (feet) --
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 3
Injury Total Serious --
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 5022
NTSB Notification Source --
NTSB Notification Date Mar 28 1994 12:00AM
NTSB Notification Time 1525
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 6 2000 10:47AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N29cf
NTSB Number ANC94IA049
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 135: Air Taxi & Commuter
Type of Flight Plan filed Company VFR
Flight plan Was Activated? --
Damage Minor
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name CESSNA
Aircraft Model 207
Aircraft Series Identifier 207
Aircraft Serial Number
Certified Max Gross Weight 3800
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 7
Number of Engines 1
Fixed gear or retractable gear Fixed
Aircraft, Type of Last Inspection 100 Hour
Date of Last Inspection Mar 17 1994 12:00AM
Airframe hours since last inspection 40
Airframe Hours 13480
ELT Installed Yes
ELT Activated Yes
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name SPERNAK AIRWAYS INC.
Aircraft Owner Street Address 1707 MERRILL FIELD DR.
Aircraft Owner City ANCHARAGE
Aircraft Owner State AK
Aircraft Owner Country
Aircraft Owner Zipcode 99510
Operator is an individual? --
Operator Name SPERNAK AIRWAYS, INC.
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address P.O. BOX 10-2255
Operator City ANCHORAGE
Operator State AK
Operator Country
Operator Zip code 99510
Operator Code ERGA
Owner has at least one certificate Yes - certificate holder
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 Non-scheduled
Indicates Domestic or International Flight Domestic
Operator carrying Pax/Cargo/Mail Passenger/Cargo
Type of Flying (Per_Bus / Primary) Unknown
Second Pilot on Board No
Departure Point Same as Event Yes
Departure Airport Code
Departure City
Departure State
Departure Country
Departure Time 1415
Departure Time Zone ADT
Destination Same as Local Flt --
Destination Airport Code BLG
Destination City BELUGA
Destination State AK
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 --