Bolting on main gear attachments: this 30 minute task stretched into 2 hours today. The main gear attachments are significant structural pieces. They span the gear channel and are integral to bracing the aft half of the airplane with the front half. Each attachment has 8 bolts through it: - 2 bolts through the lower aft longeron. - 2 bolts through the aft gear upright (to which the outboard seatbelt bracket is attached). - 2 bolts through the forward gear upright. - 2 bolts through the forward gusset that connects the gear channel with the center spar.
That said, there was a significant amount of wiggling and adjusting to get them placed just right (over their already drilled holes) and a whole bunch of contortions to get two wrenches on either side of the fuselage wall in order to tighten them all up. The most fun bolts were the two that were aft of the (already riveted into position) lower seat back, the two lowest bolts below the aft and forward gear uprights, and finally, the two bolts in the aft gear uprights that interleaved with the 2 bolts that hold the outboard seat belt bracket in place. After more than a few false starts and a couple of do-overs, all 16 bolts are in place and torqued. I guess I can add some torque seal to them now - I have no intention of removing them again!
Pilot side main gear attachment from the inside. Integrating with seat belt bolts was a challenge.
Behind the passenger seat back - this was a fun one to tighten up!