I’ve developed a few smoking rivets at 950 hours or so, belly skin, at F-808, photos attached. QB fuselage, vintage 2005 or so. The rivets appear to be driven acceptably. There are several possible fixes. Right now I'm more interested in the cause... which may change the best choice of fix.
Offhand (no hard evidence), I’d guess the belly skin between F808 and F809 may be pumping due to exhaust pulse. I use a 4-into-1 with a 45 degree downturn. The typical exhaust belly stain runs the full length of the aft skins.
Mine also lacks the portion of the lower cowl exit which normally extends a few inches below the plane of the belly.
The skin forward of F-808 is braced by the two big baggage floor ribs. I have a dollop of silicone injected between the belly skin and the floor forward of the spar, where the floor ribs come to a point and cracking is common at the aft most rivet. Still crack-free there.
So, looking for comparative data. Anyone reporting loose rivets at 808?
Offhand (no hard evidence), I’d guess the belly skin between F808 and F809 may be pumping due to exhaust pulse. I use a 4-into-1 with a 45 degree downturn. The typical exhaust belly stain runs the full length of the aft skins.
Mine also lacks the portion of the lower cowl exit which normally extends a few inches below the plane of the belly.
The skin forward of F-808 is braced by the two big baggage floor ribs. I have a dollop of silicone injected between the belly skin and the floor forward of the spar, where the floor ribs come to a point and cracking is common at the aft most rivet. Still crack-free there.
So, looking for comparative data. Anyone reporting loose rivets at 808?
Attachments
Last edited: