This quote is also from my addendum (supplement) to my first report. (Continued from previous day's quote. These quotes should explain more why I dubbed myself "The Last Inspector".): Another example: When I was assigned on the 747/767 EBU (Engine Build Up) line I wrote NCR (number) on 747 unit L/N (number) for a clearance of .XX", that should have been a minimum of .XX" (yes, I know that should have been easily visible to any inspectors eyes, regardless of calibration, but you only see what you want, or think you are allowed, to see), between a pneumatic tube on the (part number) plumbing installation and an adjacent vendor bracket on the top of the (part number) engine core. A drawing change resulted from my tag (see drawing (number) sheet 1 revision A). I believe the installation I wrote up originally was the 785th installation inspected prior to the write up of this design error that made attaining the minimum drawing required clearances impossible. The reason that this went on for so long without being fixed, in addition to (the) intentionally overlooking of it by inspectors to save themselves from being "God Bless" or "Furniture Store Going Out of Business for the Final Time!" sign holder-uppers, was that the inspectors, and sadly, the engineers that designed the installation, misunderstood the design requirements as written. Our PI had a section entitled something like "fluid tubing requirements" that gave the .XX" minimum dimension I wrote the installation up against. Other inspectors, using their own individual "common sense," and not a perusal of the drawing and specifications I used, concluded that "fluid tubing" did not include pneumatic tubing. Logical enough, if you never read the (document I.D.) spec, as most inspectors probably hadn’t, called out on the PI. So they "inspected" pneumatic tubing, if they felt like inspecting it at all and did not just roller stamp the job, to the requirements of (spec I.D.) for clearance, which are not as strict as the clearances on the drawing, and call out a minimum of .XX" clearance, which most of these installations would still be unable to be built to, I believe. Anyway, (spec I.D.) defines "fluid tubing" as tubing that carries a liquid or gas at positive or negative pressure, if I remember right. If you peruse the noted NCR you’ll probably find that engineering (I don’t know if it was Liaison or Project engineering) attempted at first to disposition the tag the same way, saying that pneumatic tubing was not fluid tubing and that the .XX" minimum clearance applied. Are aerospace engineers, who design aircraft that carry millions of people, and who can’t read drawings and specs scary? I think so. Comments are closed.
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Author:The Last Inspector Archives
November 2018
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