16 hours for this? what the heck?!? But yeah, including troubleshooting, research and a side project for my hangar neighbor.

This week I tried to arrange my workflow so I'd always have something to do while waiting for epoxy to dry. So there was lots of stuff done in little chunks over several days, which is never the most efficient way for me to do something.

Anyway, I got the elevator tip/counterweight fairings done early in the week and kept coming back to this as the same time I was working on the rest of the fairings.

I started by permanently installing the trim servo in the l/h elevator. The wiring coming off of that is only a few inches long, so the builder is faced with a choice here;

Option 1 is to install a connector here from ships wiring. That has a couple of downsides. in order to remove/install the elevator, you would have to remove the servo which is not ideal for paint shop considerations. Plus in order to do that, you'd have to leave enough service loop in the wiring to actually get the servo out so you could reach the plug to disconnect it. This means you've got extra wire just flopping around in the elevator, crammed up in there with moving parts and adding weight in an elevator that's already close to being too tail heavy because of the servo and linkage in there, even with a full sized counterweight up front.

Option 2

Splice onto the servo wiring, extend the bundle under the empennage intersection fairing and add connector there, so that when you remove the elevator you don't have to remove the servo.

Ordinarily, I'm loath to splice a wire and then just add a connector a couple of feet away, but in this case it makes sense, especially since I know this has to come back apart right after phase one for paint, so I went with option 2.

I spliced a length of 5 conductor trim wire onto the servo by means of d-sub pins covered in heat shrink. Environmental butt splices would have been my first choice back here but even though raychem says that their red ones are good down to 26 gauge wire, I've never had good luck getting them to crimp tight enough. there just isn't enough conductor for them to squeeze down on unless you fold it back on itself. plus they're pretty bulky and heavy for this application.

Also, by using d-subs back here if the servo ever goes bad, I have the option of feeding the wire back into the elevator far enough that I can get the servo out and un-pin it back there without taking the elevator off, I have a lot of faith in d-sub pins when it comes to crimping stuff on wire this tiny and consider this is a "semi-permanent" splice.

I covered my new wire with snakeskin chafe protection, fed it out of the elevator and taped it out of the way while I was installing and rigging the elevators.

I had previously adjusted the elevator heim joints and had everything rigged properly in the garage. The r/h elevator was still dead nuts on. It swung freely and when you let go it flopped nose down as expected. The l/h one, even though all the rig pins went in and it swung okay, seemed a little stiff. I could easily move it with light fingertip pressure, but once I stopped, it stopped. It didn't continue on to its nose down position as I would have expected. I added a couple of washers under the nut on the inboard lead counterweight attach screw to ensure the mass balance is indeed nose heavy and also did some experimenting with removing different rig pins which revealed that the inboard heim joint needed another 1/2 turn to get it truly in line so that the elevator moves through it's whole range. i.e. light fingertip pressure to get it going, almost no friction, and a natural tendency to swing nose down.

note- in the final configuration, they are supposed to be statically balanced. i.e. when not attached to anything, including each other, they should hang level, not nose heavy or tail heavy. However, a bit of nose heavy isn't really going to hurt anything other than aerodynamic efficiency. In fact the build manual tells you to leave them a bit nose heavy until paint because paint will add weight aft of the balance point, then achieve static balance by drilling holes in the lead to balance them afterward. What you want to avoid at all costs is having them tail heavy, which can lead to aerodynamic flutter and catastrophic structural failure in flight. This is the reason for the big lead counterweights in the first place.

Anyway, the l/h one was good, then it wasn't. I can surmise that the reason for this was when I did SB-00036 REV 3, it has you add a doubler to the aft face of the aft h/s spar and replace the steel hinge parts with new ones that are dimensioned with the holes relocated the thickness of the doubler, which without looking it up, I seem to remember being .060". Vans machining precision is good, but it's easy to see how something could have gotten off by a teeny amount with changing all that out. Especially when you consider that the 1/2 turn adjustment that was required to bring it all back in line equated to a difference of only about .020". Certainly not enough to precisely identify with the naked eye when sighting down a row of 3/16" holes.

Later during rigging, I noted that the required washer stackup at the center bearing changed as well by the thickness of I believe one washer. I took pictures and included them below for future reference, but what I ended up with in addition to the big washer next to the bearing was two regular washers on the left and a regular washer and thin washer on the right

Once I was sure everything was set correctly, I pulled the elevators back off, torqued down the heim joint jamb nuts to 80 "/lbs with a crows foot, and reinstalled with appropriate hardware.

I noted that with the AN3-7A bolts called out, there was barely 1 thread showing past the lock nut. While this is the minimum allowable for a fiber lock nut, it seemed kind of odd, so I investigated more closely. Normally, an AN bolt is supposed to have the non threaded shank just barely protruding through whatever you're bolting up, and you take upon that space with washer. In this case, The -7 bolt was just about 1 thread too short.

No problem. I'll replace with a -8 bolt....Wait, why can't I find any AN3-8A bolts in my stash? I check online and don't see any at Spruce either.

The next day, I swing by work and mention that Spruce doesn't have these and when Airparts opens I'm going to give them a call and see if they have them. Out of curiosity we look in the crib which has every piece of hardware in the universe. Turns out we stock up to -7A, then skip to -10A, just like Spruce. Shop Manager/IA is now curious as well. He gets into the company internal parts tracking system. Turns out that out of all of Cessna/Beechcraft/Hawker/Textron Aviation, the only place AN3-8A bolts are used is in a now defunct Hawker product that was designed back when the Brits owned Hawker. The listed supplier is Textron Specialty Fasteners. There is a lead time and they cost about $20 a pop.

Second IA is hanging out so he starts looking online out of curiosity and discovers the almost complete non-existence of AN3-8A bolts. At this point, including me there are now 5 A&P's in the room, 2 of them IA's, and none of us realized that we've evidently never seen or used that particular bolt for anything.

So, the options are to either to go up to a AN3-10A and start stacking up washers, or do what Vans obviously intended and what 12,000 other RV builders have evidently done, and just use the hardware called out on the print.

Armed with this knowledge, I went back to the AN3-7A that's called out. I did use a thin washer here just to give myself an extra thread through the lock nut.

With that resolved, I rigged everything up and confirmed elevator travel with a digital inclinometer. The average numbers I got from taking repeated readings at different points span wise was 27 up and 25 down. This falls within spec.

I then returned to the trim installation. I installed a d-sub connector on the aft deck to join the ships side wiring to the trim servo. Followed up by routing/securing so that there was a good service loop on both sides as well as free wire to allow for elevator movement while still insuring that there was zero chance for anything to come loose and get tangled in the flight control rigging. A jammed flight control is my own personal phobia and I've taken great care on this airplane top make sure there isn't even a remote possibility of something coming loose and getting tangled up.

In order to do this, I needed to add a couple of wire tie mounts. The adhesive backing on these is just 3M double stick tape and while it sticks great, sooner of later it always fails, so I typically scrape that stuff off and glue them on with E6000 or something. In this case, the front one is glued on with RTV, with a healthy smear front and back to give the bundle some chafe protection against the spar. The aft one that you can see on the aft deck just in front of the aft h/s spar is somewhat critical in that if it comes loose, the wire bundle would be free enough back there that elevator movement could cause it to rub on stuff. With that in mind, I installed it to the aft deck with a pop rivet. It ain't going anywhere and now I have full elevator range of motion with no chance of anything rubbing, a nice gentle radius for the wire bundle to flex through.

With that done, I wanted to ops check the trim, and while it worked as expected with the hat switch, I couldn't remember how to get the indicator to show up on the G3X. I spent the next hour on VAF and the Garmin manual trying to figure it out before I almost accidentally stumbled on the correct field to touch to get into the calibration menu and set that up. In the end, all is well.

Since everything is effectively done back there, I decided to install the empennage intersection faring. I was just finishing that up when my hangar neighbor Ron Hart popped in looking for some help weighing his RV6A. He had just finished installing a full Dynon panel and needed a new W&B to wrap up his condition inspection.

I don't know that I've done a full weight and balance since A&P school, but it was a fun side project that took about 90 minutes or so and refreshed my memory about how that actually gets done, plus I got to hang out and talk airplanes with a new friend. Met his wife and also the A&P who's signing off his Condition inspection, who invited me to use his aircraft jacks when it comes time to get my plane back up in the air to align the gear leg farings, Bonus!