Adding More Parts To The Fuselage/Tail Cone

The plan is to hold off on fully riveting the side skins onto the fuselage until after the rudder pedals are installed. The last time the side skins were on the fuselage a test was made to determine if the forward half of the side skins were not Clecoed, could the skins be easily flexed enough to allow access to install the rudder pedal mounting bolts? The hope is to  install the rudder pedals and tighten the fluid fittings without needing to crawl into the cockpit to tighten the hardware. There seemingly was enough room, so will try that tact when mounting the rudder assembly.

In the mean while, there is still plenty to do ... so continued adding parts onto the fuselage/tail cone assembly beginning with the F-1207E-L&R shoulder strap lugs. The lugs attach primarily to the upper skins of the tail cone but also tie into the baggage bulkhead as well. These lugs become the mounting point for the pilot and co-pilot’s safety harnesses and were machine countersunk last year for the flush rivets being used on the DOG Aviation RV-12.

Sliding the left F-1207E shoulder strap lug into the slot in the baggage bulkhead and securing with Clecos. The right shoulder strap can be seen in the foreground secured with Clecos and ready for riveting.

Using the pneumatic rivet puller to rivet the right F-1207E shoulder strap lug onto the top skin of the tail cone with flush rivets.

Decided this would be a perfect time to rivet the F-00062 ADAHRS stiffener in position. This stiffener was not part of the original RV-12 kits. However that has changed ... as Van’s began receiving reports of erratic movement of the ball in the Dynon SkyView turn coordinator and with the help of a couple of builders, Van's isolated the issue. The erratic movement was ultimately traced to prop-wash creating flexing and vibrations of the tail cone’s top skins in the area where the ADAHRS unit is mounted. The fix was to add a stiffener rib part number F-00062 just forward of the ADAHRS unit. This rib makes a HUGE difference in stiffing up the area where the ADAHRS mounts … so builders of older RV-12 kits will want to add this stiffener. I forgot to take a photo of the stiffener after it was riveted in place … but prior to riveting, the F-00062 rib can be seen in its approximate position in the fifth photo on the post dated 4/24/2015.

Riveting the F-00062 ADAHRS stiffener rib onto the upper skins of the tail cone just forward of the Dynon ADAHRS unit.

Prior continuing on mounting left F-1273 baggage corner skins decided it would be a good idea to place a dollop of silicone on the bottom skin to secure the AOA tubing on the bottom skin to keep it well under the flaperon torque tube which will be installed in the future. This needed to be done at this time because the baggage corner skin will close off easy access to this area.

AOA tubing set into a blob of silicone securing the tube to the bottom skin of the fuselage.

While the silicone sets up on the left side of the fuselage, moved over to the right side and began working with the right F-1273 baggage corner skin. The baggage corner skins close out the opening between the side skins and the fuselage’s bottom skin and sit UNDER  BOTH the fuselage side skin and bottom skin ... but OVER the tail cone skin. This skin was a bit challenging because the bottom skin has very little flex because only the outer row of rivet holes is open. The dimples for flush rivets make sliding the skin into position hard because the bottom skin has very little play. The baggage corner skin needs to be slipped up under the side skin about 1/2" higher than its final resting place so the bottom edge of the corner skin parallels the outer edge of the bottom skin ... then it can be slowly worked down and under the bottom skin.

Mike’s creeper came in handy to get under the fuselage to begin working the right F-1273 baggage corner skin under the fuselage’s bottom skin.

After winning the fight with the right corner baggage skin, decided this was a good stopping point for the day.