If you’re an engineer or suffer from another nervous complaint, look away now.
While considering a question PM’d to me, Walter’s posts came to mind. Essentially, he is talking about what would be a Service Engineered Modification which hadn’t been appraised or trialled properly and for which, perhaps, no proper instructions had been prepared. That is, almost every rule in the airworthiness book had been breached. A common enough occurrence, as pointed out by many fatal accident BoIs and the Public Accounts Committee.
It made me think of a SEM which had been fitted to a helo in the late 80s, and remained there until 2002. It HAD been through appraisal, industry had stated “Yes, it’s physically safe, but it doesn’t work, therefore the notional operating instructions are worthless” or words to that effect. This was ignored, the mod kits assembled (another breach, but move on….) and fitted. The crews soon discovered something. It seemed safe, didn’t work and the instructions were crap. What do you do now?????
Well, the usual reports were raised and, independently, the MoD(PE) aircraft project office (who of course have nothing to do with SEMs) offered to fix it. (Informed opinion, later proven correct, was that the design was “95% ok, but the 5% was a howler”). All were ignored and the squadron told to get on with it. What do you do now???
Answer. You, the aircrew, take tools onboard, cut the SEM wiring out, bag it and stuff it under your seat. When you return, you naturally report the SEM doesn’t work. The maintainers promptly reinstall it, test it as best they can (but of course it doesn’t work), you take the aircraft (and wire cutters) out again and………… For years on end until replaced by a proper Design Authority mod.
My points are these. Do not lightly dismiss things which seem impossible. In the above (very real) example one only had to go up one level to reach the common denominator with, in engineering management oversight terms, Chinook. Now go through 00-970 and 553 and tell me how many breaches I mention, which everyone at the air station accepted and put up with, because they were told to. Oh, and the PE project manager who offered to make the system and aircraft functionally safe was crucified by the same management team.
You can look now.