VG-21 Squadron

MAINTENANCE ITEMS

Parts Manufacture

The following information is based on an article printed in the November 2004 issue of “AOPA Pilot” magazine and deals with FAR21.303 rules governing replacement parts on certified aircraft. Basically, we are required to use parts made by the certificated airframe and engine manufacturer. Or, in some cases, a company will obtain FAA approval (PMA) to produce a part that can be used in place of the part made by the certificated manufacturer. Another case where different parts can be used is “standard parts” such as hardware built to certain standards (NAS, AN, MS and SAE). In other words, parts as good or better than the identical part used by the manufacturer. This now includes such items as resistors, diodes, transistors, and other electrical items. The next application is similar to the PMA parts and that is parts built to a technical standard order or TSO. This covers common production parts such as tires, seat belts, instruments, and avionics.

Now comes the part of great interest to our VG-21 owners that covers “owner produced parts”. In a nutshell, you, the owner, can have a part made as long as you (A) provide the design or performance data, (B) provide the materials, (C) provide fabrication process, and (E)) provide quality control or supervise the part manufacturing. It also states that the owner can hire someone to make the part as long as the owner fulfills the conditions for parts manufactured and does not make the part for the purpose of selling. The part must be used on the owner’s aircraft.

Recently, I received a request for help locating landing gear torque links. None were found. So we used the above procedure for parts manufacture. Fortunately, we have a modem aviation-related machine shop on our airfield and armed with manufacturing drawing and the required materials, the request for new links has been fulfilled. The good news is the machine shop equipment is computer operated so additional links can be easily made. At first I thought the price for the six links we had manufactured was high until I saw the purchase order for a Cessna 310 nose gear lower link - $1,800. Based on what the aluminum bar stock cost plus the cost of bushings and grease fittings, and the anodizing process, the cost per link is less than $200 per link. Two links are required per gear leg. So if you need torque links, contact us as we can as your mechanic agent.

Annual Inspections

I’m asking for feedback from you members. This past year one of our member’s Varga was disassembled to a great degree for repairs at our airfield. I paid an active part in these repairs. It was my observation that this aircraft had not received a decent annual inspection in years. I made the suggestion that the next annual be done at a maintenance facility on our field and the owner agreed. I then produced a customized job card for this task and I am proud to report it worked out well. What I’m asking is should I make this document the maintenance item in the next Newsletter?