I started today’s session by riveting the F-14110A and F-14110B Crotch Strap Brackets to the Seat Ribs. The two Brackets are attached by 10 AN470AD4-4 rivets. Shown below is one of the two assemblies. Four K1000-08D nutplates were also attached to Crotch Strap Brackets
Five rivets on the side.....
.....and five rivets on this side.
The next step is to flute the upper and lower flanges of the F-01415-L & -R Outboard Seat Ribs (larger two Ribs below) and the F-01423A-L & -R Outboard Baggage Ribs (smaller two Ribs below) until the curvature of the Rib webs matched the outboard edge of the F-01484 Center Bottom Skin. Pictured below are the Ribs and Bottom Skin.
Here is the right Outboard Seat Rib riveted to the Bottom Skin. You can see the “curvature” of the Bottom Skin compared to the “straight” Seat Rib.
Here is the opposite side of the same Rib. So, these Ribs (one on each side) had to be fluted to “bend” the Rib to match the curvature of the Bottom Skin.
In the picture below, the bottom Rib has been fluted and matches the Bottom Skin. I started on the spot where the curvature was to begin on the Rib and worked aft. It took several passes to get the curvature correct, but it was fairly easy. I fluted a little at a time until the curvature matched the Skin.
As a comparison, a fluted Rib and a non-fluted Rib are shown side-by-side below. To get the curvature correct, the Ribs had to be fluted WAY more than normal. Both the top and bottom flanges had to fluted as equally as possible to match each other and the Skin.
Here is another picture of the Outboard Seat Ribs (left) and Outboard Baggage Ribs (right).
Next, all the Inboard Seat Ribs, Crotch Strap Assemblies, and Seat Ribs were bolted to the F-01404 Bulkhead as shown below.
Here is an excerpt from the plans that show the 14 bolt locations and sizes.
Close up of the aft left side.....
.....aft right side.....
.....overall view of the forward side.....
.....right forward side.....
.....and left forward side.
