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Heard a story about a 737's APU door that got me thinking
A guy at the hangar in Tulsa was talking about a plane that kept having pressurization issues. Turns out, the APU door seal was installed with a tiny twist, maybe 5 degrees off, and it was enough to cause a slow leak nobody could find for weeks. It made me realize how a small thing you might not even see can cause a big headache. Anyone ever run into a sneaky seal problem like that?
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faith_perez2mo ago
We had a Cessna Citation with a cabin that wouldn't hold pressure above fifteen thousand feet. The mechanics checked everything twice. The fix was a one inch strip of speed tape over a barely visible seam in the baggage compartment liner. It was just a tiny gap in the adhesive, but it bled off pressure for a month. It's crazy how something that small can ground a jet.
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robert2752mo ago
Ever read about that 737 where the door plug seal was just a bit out of spec? Heard it was a similar kind of ghost leak.
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craig.reese17d ago
Right, I've been on a few jets where the leak check guys spent two days chasing a 0.2 psi drop in the cabin diff pressure. The thing that always gets me is how the air molecules don't care about the size of the leak, they just follow the pressure differential. Had a Learjet once where the leak turned out to be a tiny, almost invisible crack in the rear pressure bulkhead near a doubler plate, it was only letting out maybe a thimbleful of air per second but it was enough to keep the outflow valve from seating right. It's like the whole system is a balancing act held together by a few thousandths of an inch and some good sealant.
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