Just chiming in with my .02 cents here.
Recently had a helicopter return from contracted maintenance with 2 cracked ribs and vertical fin with enough damage to have to be re-skinned due to smoking rivets.
The point that I am trying to make here is not all smoking rivets can be just ignored.
In the first picture shows the result of leaving smoking rivets unattended. This started from one rivet loose ending up with 2 rows of rivets loose. There is 2 ribs showing damage from a Bell 412 helicopter. The rivets, outer skin and supporting ribs in time all showed signs of looseness.
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2nd picture shows the 2 rows of rivets worn. Note ribs could not be viewed above or below or from the front due to boxed in structure.
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3rd picture shows rib with approx 2.5 feet of rib structure cracked and broken off providing no support.
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4th picture show the inner skin damage where the rib would vibrate damage between .015 to .025 on a .080 aluminum skin on the load bearing side.
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