Being competent at inspecting is not a gift like the natural ability to sing. It is a unique and independent skill-set that is typically backed up by research, and a dedicated effort. Regardless if you’re a technician conducting a scheduled inspection or a QC Inspector at a Repair Station, being a competent “Inspector” is a crucial responsibility to the Safety of Flight.
When we step off into the realm of “Inspector”, the only assumptions we can apply is that it is WRONG, until proven correct. As we all know in aviation its not normally the big items that go south, its typically the incidentals, the little things that cause the major problems. If we couple our fundamental approach of “Its WRONG” until proven correct with the knowledge of the little things cause the problems into our inspection efforts; we find the correct servo installed, but with incorrect hardware or incorrect hardware stack-up.
I remember conducting a routine scheduled inspection of a Tailboom for the conventional “Security, Condition, and Attachment”, blah, blah, blah. When I actually looked at the rivet heads about 2/3 of the rivet heads were sanded off, on the vast majority of the external rivets in the Tailboom. Obviously the work of a pneumatic sander at the last paint job, 4 years earlier. How many inspections had this tailboom had since it was last painted, a bunch.
Its important we know the limits or what is correct, so we have the ability to identify the WRONG. If I can see the prop has been profiled on the tip and leading edge, I have no other option than to measure the span and chord and compare it to the limits. Sometimes it’s hard to measure the depth of nicks, dents, damage, or corrosion. But if you buy a set of electric guitar strings (check out the 12 string set) they go down to .008” and step up in .001” increments, and they make an excellent set of wire gages.
When you’re trying to inspect inside a confined area especially when it coated with zinc chromate primer, I have found using a piece of white card stock cut up to fit my need and positioned in the right place will create a huge light reflector that really amplifies the light source and allows me the opportunity to get a good look at those hard to see spots. Applying a little photography 101 to aircraft maintenance, hey I’ll take anything I can get.
I have always used AC43.13 as my go to book for major repairs and alterations. But guess what else is in the title “Inspections”. What an awesome resource. In there I learned wire bundles are to have a minimum of ½” clearance between moving parts like cables, control rods, and belcranks. I didn’t know that until I made a concentrated effort to enhance my skill-set as an “Inspector”. There is a ton of good stuff in that book if you really want to improve your inspection skill-set.
When you need to do a tap check for debonding, some hangars are pretty loud. But I found if you do your tap check using a mechanical stethoscope it’s a completely different tap check. And if you think you have a bearing that may be getting rough, try listening to that bearing with your mechanical stethoscope. Word to the wise, DON’T use a doctors stethoscope, seriously.
Here is how I test “Inspector” competencies: go inspect that aircraft and let’s take a look at the discrepancies you found. After we look them over I make you this offer: What if I offered you $200.00 for every legitimate discrepancy you could find above the discrepancies you have already identified, would you like another look at the aircraft?
Its never been what we found that concerned me, it’s the what we didn’t find that concerns me.
Please allow me to Thank You for your continued contribution to the Safety of Flight