Check at annual
 

I was doing an annual on N12M (TSIO 360 C) today, removed the induction air filter to the turbo, Looking down into the box I saw something that didn,t look right, at the bottom of the box lay the alternate air door, it had detached from it's 2 attaching revits and was trying to go through the turbo. I have no idea how long it has been loose in there but not to long by the look of the scratches on the door where it hit the turbo inlet blades. Attached are a couple of pictures I took, hope this helps. I don't need to tell you what would have happened if that door had gone through the turbo.
Be sure to check yours at your next annual !!!!!!!!!!
Fred N358

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Fred N358

a friend of mine just lost his v-tail on takeoff; however it was carberated and the alt air door spring broke and folded back over the intake of the carb, killing the engine @ 100' after takeoff with his kids aboard. had a large runway and bellied in in, with all safe. a/c is scrap. it usally isn't the big buck items that cause big expenses as in this case a buck spring cost 60k.

I had a similar, although less disasterous, thing happen to me in a rented Grumman Tiger years ago. A rubber seal had been allowed to deteriorate and it came loose inside the carberator throat, and part of it sucked down and killed the engine. This happened at 4000' IFR right over the top of San Francisco International, so it ended with no problem (ceiling turned out to be about 1500' or so).

Worst part was, my rather hard dead stick landing must have dislodged the seal. While I was in the air, I could not restart. But on on the ground, it ran perfectly. I refused to fly the airplane until they found the problem, and some kid flew down on the airlines and flew the airplane back (unrepaired) over the mountains at night. The next morning, the FBO mechanic found the problem.

Kevin

Our 1977 P-model had the alternate air door come loose also, but in our case the rivets holding the magnet were letting go, but fortunately we caught it during a 25-hour check before any damage occurred. It's good to check the door hinge AND the magnet attach points every on a routine basis other than just at annual because of the vibration and air flow in these areas.

SkyKing