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Unapproved Parts /Inventory Audit Training

You ask yourself “Why do I need to know anything about Unapproved Parts? Aren’t they the same as “Aftermarket Parts”?   The answer is a resounding “NO”! In the aircraft business the use of unapproved parts, counterfeit parts, or parts missing an FAA approval can not only be illegal but may harm you or your aircraft.  Maintenance shops get their nuts and bolts from many sources — some of which are OK, some of which may not be OK! Have you ever taken a good look at the nuts and bolts used to put an aircraft together? Have you ever considered that, in many cases, lives may be hanging by a thread?  Check out my article Hanging by a Thread  listed under Articles.  Here is a report from the National Transport Safety Board "NTSB" that shows the importance of bolts and fasteners...Please read...

                                         National Transportation Safety Board

                                       Aviation Accident Final Report


The aircraft sustained substantial damage during a forced landing following a loss of engine power. The pilot reported the airplane experienced a propeller overspeed condition followed by a fluctuation in oil pressure. The pilot stated the engine started "banging" and lost power a few minutes later. The pilot performed a forced landing to a bean field, during which the main landing gear collapsed. Inspection of the engine revealed the number four engine cylinder connecting rod cap and cap bolts had fractured. A metallurgical examination revealed that the nut of one of the connecting rod cap bolts was partially engaged. The connecting rod cap showed evidence of fatigue cracking along the fracture surface. Fracture features of both connecting rod cap bolts indicated the bolts had separated due to overload.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be: A loss of engine power due to a loose connecting rod cap bolt and the resulting fatigue failure of the connecting rod cap. A related factor was the unsuitable terrain.

The FAA for over thirty years has focused on the proliferation of unapproved aircraft parts. These parts include, defective, counterfeit, manufacturer overruns, and other parts missing an FAA approval basis for installation on Type Certificated aircraft. There is a FAR provision for “Owner-produced Parts”, but it is very narrow in scope, and the part produced must be Airworthy and only installed on the producing owner’s aircraft. When I was the Technical Advisor to the DOT-IG many years ago we actually discovered that about 39% of the inventoried parts used to maintain the FAA’s own aircraft lacked any appropriate traceability and were therefore deemed unapproved. Defective aircraft parts, per the NTSB, have been the cause of at least 166 incidents. Parts Inventory is a selected item in any Repair Station for FAA inspection.

We can visit you and conduct a complete Inventory Audit for FAR compliance. It usually takes one or two days. The cost involved is $125 per hour. The usual FAA fine for violations can be found in FAA Order 2150, far more. 

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