Aircraft Accident/Incident Report

Stevensville, Montana 59870
Friday, November 17, 2000 16:30 MST

NTSB Narrative Summary Released at Completion of Accident

During a descent, and while passing through approximately 8,000 feet mean sea level, a sudden, violent airframe vibration developed in the twin engine Piper PA-30, and the pilot shut down the right engine. He then noticed a portion of the one of the propeller's tips missing. Metallurgical examination of the blade revealed a fatigue fracture initiating from a dent about 0.2 inch from the leading edge of the blade. The dent measured approximately 0.07 inch wide in the chordwise direction and about 0.03 inch deep and was covered with flat black paint. The propeller log indicated repeated historical occasions whereby the propeller had been dressed and painted. FAA Advisory Circular 43.13-1B/2A, 'Aircraft Inspection, Repair & Alterations' states in Section 4. 'Repair of Metal Propellers,' paragraph 8-73(a) 'Flaws in Edges,' that the mechanic should '...Exercise care to remove the deepest point of the injury and also remove any raised metal around the edges of the injury....'

NTSB Probable Cause Narrative

Fatigue of the right propeller blade resulting in an in-flight separation of the blade tip. A contributing factor was the improper maintenance procedure.

Event Information

Type of Event Accident
Event Date 11/17/2000
Event Day of the Week Friday
Time of Event 1630
Event Time Zone Mountain Standard Time
Event City STEVENSVILLE
Event State MONTANA
Event Country --
Zipcode of the event site 59870
Event Date Year 2000
Event Date Month 11
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 Unknown
Investigator's weather source Weather Observation Facility
Time of the weather observation 1656 Mountain Standard Time
Direction of event from weather observation facility (degrees) 330
Weather Observation Facility ID MSO
Elevation of weather observation facility 3201
Distance of event from weather observation facility (units?) 36
Time Zone of the weather observation MST
Lighting Conditions Day
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Clear
Sky Condition for Lowest Ceiling None
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 10
Air Temperature at event time (in degrees celsius) -3
Dew Point at event time (in degress fahrenheit) -9
Wind Direction (degrees magnetic) 60
Variable Wind Indicator Unknown
Wind Speed (knots) 3
Wind Velocity Indicator Unknown
Wind Gust Indicator Not Gusting
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) 30
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 5
Injury Total Serious --
Injury Total All --
Investigating Agency NTSB
NTSB Docket Number (internal use) 1024
NTSB Notification Source --
NTSB Notification Date Nov 18 2000 12:00AM
NTSB Notification Time 1118
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Jul 2 2001 3:17PM
User who most recently changed record MONR
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N7062Y
NTSB Number SEA01LA023
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed VFR
Flight plan Was Activated? --
Damage Substantial
Aircraft Fire None
Aircraft Explosion None
Aircraft Manufacturer's Full Name Piper
Aircraft Model PA-30
Aircraft Series Identifier PA-30
Aircraft Serial Number 30-74
Certified Max Gross Weight 3600
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 2
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Annual
Date of Last Inspection Jan 18 2000 12:00AM
Airframe hours since last inspection 84
Airframe Hours 4375
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site Unknown
ELT Type --
Aircraft Owner Name FOX, NORMAN A.
Aircraft Owner Street Address 1323 MOUNT ELLIS LANE
Aircraft Owner City BOZEMAN
Aircraft Owner State MT
Aircraft Owner Country
Aircraft Owner Zipcode 59715
Operator is an individual? --
Operator Name CHAPMAN, DOUG S.
Operator Same as Owner? No
Operator Is Doing Business As --
Operator Address Same as Owner? No
Operator Street Address 5915 ESTATE LANE
Operator City BELGRADE
Operator State MT
Operator Country
Operator Zip code 59714
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 BZN
Departure City BOZEMAN
Departure State MT
Departure Country
Departure Time 1540
Departure Time Zone MST
Destination Same as Local Flt --
Destination Airport Code 32S
Destination City STEVENSVILLE
Destination State MT
Destination Country
Specific Phase of Flight --
Report sent to ICAO? --
Evacuation occurred --
Date of most recent change to record Oct 31 2002 4:14PM
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 --