Aircraft Accident/Incident Report

Lapeer, Michigan 48446
Monday, June 3, 1996 14:55 EDT

NTSB Narrative Summary Released at Completion of Accident

According to witnesses, the accident pilot reported on Unicom that his 'flap bracket had broken.' A pilot who was on the ground near the accident site reported that he observed a 'violent flutter' on the right wing. Examination of the right flap revealed the inboard flap push rod was fractured at the end cap. The push rod welds exhibited 'porosity and secondary cracking indicative of poor welding techniques.' The inboard cruise flap push rod 'exhibited a thumbnail crack, which may have indicated failure by high stress, low cycle fatigue.' The outboard cruise flap hinge was fractured. Examination revealed the hinge was constructed entirely of composite material. The kit manufacturers drawings specify an aluminum core for the hinge. Differential scanning calorimetric analysis of the composite cruise flap skin revealed the vinyl ester matrix material was 'not fully cured.'

NTSB Probable Cause Narrative

incomplete cure of the bonding material in the cruise flap, improper material in the cruise flap hinge, and improper welding of the cruise flap push rod end caps. Factors were delamination of the cruise flap, partial failure of the cruise flap hinge, and fatigue failure of the outboard cruise flap push rod.

Event Information

Type of Event Accident
Event Date 6/3/1996
Event Day of the Week Monday
Time of Event 1455
Event Time Zone Eastern Daylight Time
Event City LAPEER
Event State MICHIGAN
Event Country --
Zipcode of the event site 48446
Event Date Year 1996
Event Date Month 6
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 Witness
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 Not Reported
Lowest Ceiling Height 0
Lowest Non-Ceiling Height 0
Sky/Lowest/Cloud Conditions Unknown
Sky Condition for Lowest Ceiling Unknown
Visibility Runway Visual Range (Feet) 0
Visibility Runway Visual Value (Statute Miles) 0
Visibility (Statute Miles) 0
Air Temperature at event time (in degrees celsius) --
Dew Point at event time (in degress fahrenheit) --
Wind Direction (degrees magnetic) 0
Variable Wind Indicator Unknown
Wind Speed (knots) 0
Wind Velocity Indicator Unknown
Wind Gust Indicator Unknown
Wind Gust (knots) 0
Altimeter Setting at event time (in. Hg) --
Density Altitude (feet) --
Intensity of Precipitation Unknown
METAR weather report --
Event Highest Injury Fatal
On Ground, Fatal Injuries 0
On Ground, Minor Injuries 0
On Ground, Serious Injuries 0
Injury Total Fatal 1
Injury Total Minor --
Injury Total None --
Injury Total Serious --
Injury Total All 1
Investigating Agency NTSB
NTSB Docket Number (internal use) 1404
NTSB Notification Source --
NTSB Notification Date Jun 3 1996 12:00AM
NTSB Notification Time 1500
Fiche Number and/or location -used to find docket information IMAGE
Date of most recent change to record Dec 8 2000 10:03AM
User who most recently changed record dbo
Basic weather conditions Visual Meteorological Cond
FAA District Office --

Aircraft Involved

Aircraft #1

Aircraft Registration Number N7033G
NTSB Number CHI96FA185
Missing Aircraft Indicator N
Federal Aviation Reg. Part Part 91: General Aviation
Type of Flight Plan filed None
Flight plan Was Activated? --
Damage Destroyed
Aircraft Fire Ground
Aircraft Explosion None
Aircraft Manufacturer's Full Name Corey
Aircraft Model CIRRUS VK-30
Aircraft Series Identifier CIRRUS VK-
Aircraft Serial Number 117
Certified Max Gross Weight --
Aircraft Category Airplane
Aircraft Registration Class U.S. Registered/U.S. Soil
Aircraft is a homebuilt? Yes
Flight Crew Seats --
Cabin Crew Seats --
Passenger Seats --
Total number of seats on the aircraft --
Number of Engines 1
Fixed gear or retractable gear Retractable
Aircraft, Type of Last Inspection Annual
Date of Last Inspection --
Airframe hours since last inspection --
Airframe Hours 65
ELT Installed Yes
ELT Activated No
ELT Aided Location of Event Site No
ELT Type --
Aircraft Owner Name ALFRED Y. COREY
Aircraft Owner Street Address 4669 SPRING STREET
Aircraft Owner City HADLEY
Aircraft Owner State MI
Aircraft Owner Country
Aircraft Owner Zipcode 48440
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 D95
Departure City
Departure State
Departure Country
Departure Time 1430
Departure Time Zone EDT
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 --
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 --