Brief Description: Fit Forward Fusalage Ribs and Top Skin
The F-746 forward engine control bracket is attached to the bottom of the F-7105A center sub panel with AN470AD rivets. I marked the bracket and drilled the 4-3/32" holes. I clamped the bracket to the sub-panel and match drilled the 4 holes to #30. I deburred the holes and set aside. Next I fit the center rib to the slot in the center sub-panel by twisting the panel as instructed. I clecoed the forward left and right ribs F-7107-L and F-7107-R to the firewall. I clecoed the left and right outboard sub-panels F-7105B-L and F-7105B-R to the forward canopy deck. I dropped in the center sub-panel and clecoed in place. Then, I used 3 8R8 screws and nuts to hold the F-7103 instrument panel in place and the ends resting on top of the canopy deck. I checked all the rib and sub-panel flanges for alignment and bent where required. I did the same for the firewall flanges. The center rib holes and firewall holes are not prepunched so I had to cleco the F-7106 forward top skin in place to align the center rib correctly with the firewall. I clamped the center rib angle to the F-601L-1 stiffener to lock it into place. I measured and marked the 5 holes for AN426AD4 rivets and drilled the holes to #30. I removed the clamp and drilled the #30 hole for the AN470AD4 rivet through the stiffener. With the instrument panel in place, I postioned the 2 F-721C attach angles using the screw holes in the panel as a guide and marked the rivet holes in the canopy deck. I also did the same with the 2 F-721D attach angles. I also fitted and match drilled the F-7108C angle to the center rib and sub-panel. I match drilled all the top skin holes to the ribs. I clamped the firewall flange to the top skin and match drilled those holes. Before I clecoed the top skin I had to drill out the temporary blind rivets holding the side skins to the F-718 longerons. I match drill the top skin holes to the side skin holes and longerons to #30 and #40 as called for in DWG 28. I removed the top skin and match drilled all the rib and sub-panel holes to #30. I
