Scott & Tanya Card RV9A build log (N4822C)

With my prop governor on its way to MT for repair (update), I’m still plugging away at the fiberglass gear fairings. The governor should be back next week.
I’ve been out at the hangar each evening banging away at the gear leg fairings and wheel pants. I had to do some “major” reconstruction of the nose gear leg intersection fairing. It didn’t really match the gear leg very well at all. I chopped it up and used expanding foam to re-form the leg transition. Then did a glass layup (or two) and popped it off the airplane. Back at the bench, trim, fill, sand, repeat.
On the main wheel fairings, I glassed in a little transition lip onto the forward half of the pant to gear leg intersection fairing. Partly to cover up my sloppy part line. So I’m doing the same trim, fill, sand, and repeat operation on those. Also, I’m beginning to work through getting the two wheel pant halves to meet cleanly. Much more to still be done there.
Finally, I’m filling and sanding the upper main intersection fairings for shape. All of this is even in the stage before first priming. I usually still have quite a way to go after the first primer is put down on composite work.

I think I figured out why the Garmin 430W didn’t seem to be sending vertical nav commands to the autopilot via the ARINC 429 interface. After reading through the ARINC output definitions in the 430W documentation, all of the vertical command statements are in the 429 GAMA format, not the base 429 format that I had configured per the GRT efis documentation. Then going back and looking at the TruTrak Digiflight II VSGV documentation, low-and-behold, it said to use 429 GAMA. I can’t imagine how many times I have read that same documentation (it must be hundreds, I almost know it by heart) and missed that critical piece. So ARINC 429 GAMA output it is. I haven’t had a chance to test fly it yet, but this will certainly produce the expected results of the 430W flying the autopilot right down the glide slope on a GPS approach!

I decided to go ahead and contact MT about the prop governor. They are currently waiting on parts for unit revision “F” and would like to update my governor when those parts arrive hopefully later this week. I guess I’ll chill and send them the unit ($1400 will do that to you). I guess there won’t be any flying for the next couple of weeks while this is resolved.
That gives me plenty of time to clean up my fiberglass work.

New Bug: When the oil temperature is high (over about 195deg.) the propeller governor is unable to maintain a stable propeller RPM on takeoff. It doesn’t over speed, but does fluctuate almost 300 rpm lower. Just a wee bit alarming on climb-out. This is a known possible condition of the MT governor that I was “hoping” that we didn’t have. No such luck apparently after 47hrs. I’m not going to even mess with MT to resolve it. It seems the concrete fix is a new PCU500X governor. I’ll get one ordered on Monday.

All I can say right now is WOW! I should have buckled down and got the wheel pants, gear leg fairings, and intersection fairings on it long ago. Rough first indications on the first .5hr test flight is +23mph at 70% power at 3000′. Not to mention some slightly cooler CHTs to go with it. Much fun! I’m still chewing on the data recorded, and much more test flying to come to fully identify the difference (it is huge).

Just in case anyone was doubting my comments about just “roughing in” some of this glass work, here are a few pictures :). The pictures actually make it look uglier than it really is. I’ll get it cleaned up between flights. This was also the first flight that I’ve been up past sunset and the first time I actually *needed* some of the lights that I installed. I was happy to have the glare shield flood light and the EFIS dimmer.

 

  

  

  

  

  

  

  

  

  

  

  

  

  

 

Another afternoon (4hrs) of wheel pant and fairing work while I waited for my Oxygen and Argon cylinder delivery. I got all of the nutplates on the wheel pants and them mounted to the gear. The gear legs are on and aligned (hopefully). I am using the Fairings-etc. intersection fairings. I have found some of the fit to be marginal on some of the pieces. I finished my day with the main gear leg to fuselage intersection fairings clecoed in place and a slurry of filler drying in place where the fairings didn’t fit so well. After that is set, I’ll have a base to reshape some of the the fairing. I’ll probably first just cleanup the filler and go fly! There is still going to be a lot of time involved in improving the fit of all these parts before they are ready for paint. I’m just going to do that in between flights.
My welding cylinders arrived. Yee Haw! I used the transfill plumbing that I purchased from Mountain High to fill up my oxygen cylinder. This worked out great. Two source transfill cylinders are definitely the minimum configuration. The initial fill of the airplane cylinder took a few hundred pounds of pressure out of the first source cylinder. There is only a few hundred pound usable range (1800-2200 psi) in the breathing cylinder. I topped it off with the second cylinder nicely. My first source cylinder is now only good for filling to less than about 1900psi.. A refill on the source cylinders are only about $15 :). This is very cool to be able to fill my own stuff in the hangar.
The Argon cylinder is for my next project to get setup to learn to TIG weld.