Scott & Tanya Card RV9A build log (N4822C)

Another couple of flights. I did my 50mi. lap to Caldwell and back. The autopilot did most of the flying (coupled to the 430 through the efis) with no disconnects. I was able to cruise at 7500′ and 8500′. That is just plain fun and smooth. The new carb and oil temp sensors aren’t any better (no more stable) than what they replaced. I did a bunch more diagnostic on them. First I wired them direct to the instrument with completely different wires temporarily. Same deal. Then fully disconnected them and hooked up an ohm meter. The resistance of the temp sensors is all over the place when you wiggle the wire at the base of the sender just a bit. Same as the old ones. I’m keeping my CHTs under control with a whole lot less power during climb.
The new mags are so-far-so-good. I had my first GRT EFIS display lockup on final. All three screens simply froze at the same time. That was a surprise. Obviously there is a bug in the v.30 software somewhere. They were fine after a reboot once on the ground. I also seem to be having the GRT Weather module failing on most flights. It also always recovers with a power cycle. During the failures, the GRT module reports fine, but for some reason can’t communicate with the WxWork receiver until they are powered off and back on. I’m slowly working on wheel pants and gear leg fairing glass work.
Even with working through all the little gremlins, I’m having a blast flying. I think I’m well equipped to work through these details. But my advice to others would be not to let things get too complex if you don’t have the patience and stamina for debugging.

I finally got a chance to do some more flying. I did three flights on Sunday. I’m back to some pretty conservative flight durations and distances in order to check the ignitions often. So far so good. I flew up in a large hole in the towering clouds and went up to eight thousand feet. This was the first chance I’ve had to experiment with wide open throttle in cruise. I also used the opportunity to do a little max climb rate testing now that I am very familiar with my temps and how to manage them. This thing really will climb like crazy if you put in all the power and point it up. I’m using much lower power settings in climb to manage temperatures better. Especially on initial climb-out.
I got the nose wheel fairing on it and got some test time on that. It was still intact after landing and no adverse effects in flight. All good.
I haven’t had any occurrences of the autopilot disconnecting from GPSS guidance since I’ve been using the Garmin 430 as main gps input into the efis.
Tanya came out to the hangar (first time in quite some time) and did cleanup duty. We have a bit of an invasion of crickets. They die in the hangar and start to stink pretty bad in such quantities. Tanya and I agreed that her efforts qualified for “Dirty Jobs”.

Rain-Rain-Go-Away!
I made it out to the hangar and got my new carburator temperature sensor installed. I wiggled the wires on the new sensors and the instrument reading is stable :). I also finished the mounting brackets for the oxygen bottle in the baggage area on the flap cover.

 

  

  

  

  

  

 

Here are a couple random tips of things that I’ve found since flying:
- Set the brake pedals tilted as far forward as possible. It is very difficult to taxi and keep the feet off the brakes.
- If you are using camlocs to attach the cowl at the sides of the firewall, don’t “scallop” the attachment piece like I did. The reason is that when installing and removing the lower cowl, the peg of the camloc in the cowl gets caught between the receptacles in the “scallops”. Also, during installation of the lower cowl, the top aft corner gets caught in the valley of the scallops. Both a big pain.

Just looking at what I have. If I were a molecule of air, I don’t think I would know which way to go…
Obviously these are the right and left cowl air inlets. The more homework I do on cooling, the more important the shape of the air inlet seems. Looking at the profile of the air inlets on the plenum top, I think there are some real improvements that could be made. We won’t really know until I start chopping it up. I am thinking that the big flat, corner protrusion looking from the inside, needs to go away. I think we could do more of a smooth transition from the forward part of the inlet up to the top part of the plenum. I’m guessing that this could have a real impact on high angle of attack flow especially.