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KatieB 01-24-2017 10:05 PM

10" G3X Touch in an RV-3B...
So after years of poking around with pipe dreams, drawings, lists, budgets, and mission evaluations, I?ve begun installing the brains of my -3. It was a long and arduous road, but I?ve decided to go with Big G. Yeah, Garmin. ?But you?re the GRT chick! What happened?? Well? it?s a long story.

The bones of my plane as it sat in the junk yard came with a Dynon D180. I sold that to a fellow VAF'er with another RV-3 and paid off my car loan. Sure, I could?ve kept it all as Tony had it, but I had way too many hours flying behind GRT Sport systems, which blew the D180 away in features. SO that was a no-brainer, even though it would add many months and a few grand to the budget requirements. (Every decision with this plane has added many months, so why not!)

I assumed for a very long time that I would put a GRT system in here. It was by far the most reliable of any system I?d had experience with, and we knew the ins and outs of how to install and operate them. The question was really, Sport or HXr? And besides, I worked there. But in 2014 we left GRT to go back to my father-in-law?s Jabiru airplane business. He had used GRT stuff since the very beginning, with most of the 120-ish Jabiru airplanes built in the USA since about 2002. We tried the G3X system in 2010, but back then it was difficult to install and we had some trouble getting the engine monitor sensors to play nicely with the Jabiru. But now, in 2015, LSA shoppers were asking pretty loudly for the new Touch system, so we decided to give it a try.

Sometime between 2010 and 2015, Garmin must have realized that amateur avionics installers needed more guidance and easier tasks than the professionals they were used to dealing with in the certified world. The new Touch system was much easier to install and the instruction manuals were more thorough. The best part about the system, however, is how fun it is to fly. Our fears and former sales pitches against the touch screens turned out to be mostly wrong assumptions. The touch screen is not any more difficult to use in turbulence than buttons. It is not prone to glare unless you wear white on a sunny day (ask me how I know...) You can?t see fingerprints unless it?s turned off. Its user interface was intelligently designed from the ground up to be intuitive and easy. It?s like using a tablet. The depth of information displayed and the ease with which you can access it is mind-blowing.

I didn?t truly appreciate its capabilities until I flew our first Garmin Touch airplane, a Jabiru J230-D with about 15 hours on it, from Tennessee to Oshkosh for ?the convention? in 2015. It was a giddy trip anyway, because I was going early to prepare for our wedding, which would feature that very same airplane. You might have read about it in AirVenture Today. Anyway, by the time I got past Kentucky, I was giggling like a 5-year-old in Toys R Us. I think my favorite screen was the waypoint information page. While my old standby GRT Sport system had most of the same information, it was displayed on a black screen with white text that blocked out all reference to map and PFD. The 10? Garmin Touch, in contrast, displays an information page for the chosen airport on the map side of the screen with a simple knob twist or two touches of the map, and you never lose your primary instruments. The airport is shown on a static map with big colorful touch tabs along one side for Runways, Frequencies, Weather, NOTAMs, AOPA Airport Directory? everything you could possibly want to know, and so easily accessible! And you could just touch the map to quickly get this information for anything.

In the year and a half since then, I?ve put a few dozen hours on the system, mostly flying cross-country. I spent many enjoyable days last summer navigating around storm systems, using ADS-B METARs and cautiously using NEXRAD radar with ATC flight following to maintain VFR and stay out of trouble. There were a few times I climbed into a GRT equipped airplane with a system that used to be my favorite thing ever, and found myself frustrated at having to punch a bunch of buttons to find what I needed. Not to mention the fact that I forgot where to find things in the menus. I got a little pissed at GRT because my friends have so much talent in that little building, but they've just fallen behind the times.

So after a long period of deliberation, I decided that personal friendships and an old brand allegiance, no matter how strong, were just simply bad reasons to pick a certain system for my airplane. Ultimately, it came down to one fact. I have FUN when I fly a G3X Touch? so that?s what I picked. Oh, and by the way, size does matter? I don?t really care for the layout of the little 7? EFIS, and besides, 10? of glass on this tiny panel is JUST SO **** COOL!

[IMG]0507161959 by jabiruchick, on Flickr[/IMG]

KatieB 01-24-2017 10:11 PM

Panel Layout
The layout of any instrument panel should reflect the intended mission profile of the airplane. I plan to use my airplane?s speed for quick, long VFR cross-country trips. I?m instrument-rated, but I?ve been flying cross country in VFR-only airplanes for so long, I don?t feel the need for IFR navigation equipment and ultra-redundancy I would want if I were to fly in the clouds. Not to mention those things cost a lot of money, and most importantly in an RV-3, a lot of weight. Just ask Paul and Louise? :D

So, because I?m VFR, a single EFIS and remote radio is ok, which means that I have room for a big screen. As a totally unplanned bonus, I also have room for Garmin?s new little G5 backup instrument? so I threw it in there for a last-resort battery-powered backup to get home if the big screen or the alternator craps out.

I made my basic screen layout in a publishing program that I?m familiar with, then flipped it to my husband, who knows AutoCAD pretty well. He drew out the basic shapes, using some of our Jabiru panel elements, and then attempted to teach me how to tweak it. I must admit that my first several hours trying to use AutoCAD, I felt like a monkey with a hammer trying to build a house. However, after learning a few key skills, I was able to do enough to really make the layout and text exactly how I wanted it. Normally we send our panel layout files to Industrial Nameplate Inc., a company in Wisconsin that prints them out on vinyl, coats them with plastic and laminates them onto aluminum, but I wanted to ?save time? (yeah right) and so I decided to try screen printing the text and switch hole locations onto my panel face. It?s been cloudy here in Tennessee for like a month, so I have yet to try the sunlight-activated screen emulsion. If I can?t make it work, INI is my backup plan, but he normally takes a few weeks to deliver anything.

Because my panel real estate is all being taken up by this gigantor EFIS, I had to find a different spot for circuit protection. I originally planned on using fuses for everything, but then i realized that a flip-down circuit breaker panel would be easy to make, and I really did want to be able to access my avionics breakers in flight. And then, in a further evolution (all in my tortured head, of course) I decided to make a narrow lower panel extension with the throttle, mixture, circuit breakers, headset jacks, cabin light rheostat, and cabin heat control. I made a posterboard mockup, taped it to the bottom of the panel and tried getting in and out of the plane without hitting it with my knees. It will make getting in and out of the plane a little more delicate, but there won?t be any sharp edges to scrape the shins, so I think it will work out ok.

Here's an older version of the panel layout. I'll try and put a new one up tomorrow sometime.

[IMG]0506161529 by jabiruchick, on Flickr[/IMG]

KatieB 01-24-2017 10:19 PM

Magnetometer Installation
One of the quirks of the Garmin installation is its super-sensitive magnetic field sensor. Like the GRT systems, the Garmin magnetometer does much more than function as a compass—it provides data to the ADAHRS as part of the calculation of the attitude of the aircraft in space. If you ask me how it does this, my answer will always be “PFM”—that is, Pure F-ing Magic.

There is a list in the installation manual of things that the magnetometer cannot be near. Basically, it’s servo motors, current-carrying wires, control cables, ferrous metals, and anything that’s been magnetized. In a plane as tiny as the RV-3, it’s a real challenge to find an interference-free spot for it. The wingtip is often recommended, but it is awfully close to the steel aileron counterweights and the wires for the LED tip lights. The tail shelf “aft deck” under the vertical stab is also a recommended location for RV’s, but in mine, it would place the magnetometer within a foot of the steel tail spring mount—and I know for a fact that it’s magnetized because I’ve poked around with a magnet so many times over the past 6 years to fish out dropped nuts and washers! It’s also susceptible to water damage from rain dripping inside the tail fairing at our great air shows. So, that’s out.

Here's the shelf after I bent the support flanges. It's just a piece of .032 out of the trim bundle from the empennage kit.
[IMG]2016-12-17_03-31-03 by jabiruchick, on Flickr[/IMG]

And the neat little mounting ring Garmin supplies with the Magnetometer...
2016-12-17_03-31-47 by jabiruchick, on Flickr

There is one place where the nearest sources of interference are the rudder cables and trim cable… and it’s halfway down the tail cone, between the longerons and a reasonable distance behind the pitch servo. I read on here and in the Garmin installation manual that some RV-8 builders mount their magnetometer on a shelf suspended across the longerons in this location. So, that’s what I did. Let me tell you, if you have a chance to install this thing before you rivet your top turtledeck skin on, DO IT! There are two mechanics at our shop and me, a halfway-wannabe mechanic, and despite the fact that I'm a well-fed Midwestern girl, I'm the only one that remotely fits back there. If I couldn’t do it, nobody could! So I did. With more grunting and swearing than a well-behaved woman would ever do. But nobody has ever accused me of being well-behaved.

[IMG]2016-12-17_03-32-01 by jabiruchick, on Flickr[/IMG]

Here it is in its new home. The camera angle makes the whole thing look a little scatty-wompus, but I assure you it's all straight.

[IMG]0114171458 by jabiruchick, on Flickr[/IMG]

KatieB 01-24-2017 10:31 PM

Avionics Shelf
The top nose skin of the RV-3 was designed to be removable to access the fuselage fuel tank, but this is an RV-3B, so my fuel tanks are in the wings. It has a tip-over canopy, which isn’t sexy like a slider…at all…but it affords the opportunity to attach the front top skin to the fuselage with screws. This is an AMAZING maintenance item! I will never have to stand on my head to work on my avionics. And, hopefully, the way I install the avionics tray and wiring will allow me to remove it if I have to dive in to service the rudder pedals, brakes, battery box, or fuel system.

Tony originally used this shelf system to mount his Dynon stuff, fuse block, manifold pressure sensor, and other little things. His shelf is too narrow for the Garmin LRUs I need, so I made a new one. Posterboard was my best friend here. I made a posterboard shelf, complete with folded-down flanges for a little “strength,” and then I cut out paper versions of my LRUs so I could play with layouts. I thought for a while that I would need to install the ADAHRS and transponder in the baggage compartment, but after some playing with the cardboard, I fit everything in the nose.

[IMG]0114171517a by jabiruchick, on Flickr[/IMG]

The ADAHRS was designed to be mounted to the back of the EFIS screen, but some experts advise against this now. The ADAHRS requires an extremely rigid mounting surface, and the panel boxes of some planes have proven to be too flexible for it. Additionally, it’s handy sometimes to remove the EFIS screen to access the avionics bay, but if the ADAHRS is hanging onto it, you have to disconnect the pitot, static and AOA lines. So, I wanted to mount it on the side of the baggage compartment instead, but the more I looked at potential designs for a mounting bracket, the more I started to like the back of the EFIS screen. The RV-3’s panel is a small semi-circle supported around the top by the .032 top skin, and my panel face is built of .062 with a piece of ¾” angle riveted to the bottom edge. I feel confident that it’s the stiffest place on the plane short of the wing spar. My husband has an aerobatic Panther with the same setup and no ADAHRS issues so far.

I didn’t have enough .032 or .040 laying around the shop for my shelf, so my RV buddy Possum brought me an old pre-punched .032 nose skin that came out of an RV-7 kit. He had already cut off one side of it for a custom part for his “insane” but beautiful Zenith 701 project. After shearing and bending it on our 3-in-1 bending brake, I thought it was still a little jello-ish so I back riveted a stiffener to it. I was able to re-use 3 holes that were already drilled into the longerons to mount the shelf, so that was nice. One hole even had a random 3/32” hole next to it which fit the nutplate perfectly. Back riveting worked fairly well for the LRU mounting nutplates, too. After prettying it up with some paint and attaching all the LRUs, I felt like I had really accomplished something-- which is something I haven’t felt about this plane in ages!

[IMG]0119171652 by jabiruchick, on Flickr[/IMG]

[IMG]0120171514 by jabiruchick, on Flickr[/IMG]

[IMG]0123171846b by jabiruchick, on Flickr[/IMG]

Robert Anglin 01-25-2017 06:35 AM

Good job
You will like it. We have much the same system in our 8, with an auto pilot and an audio panel. I may never be smart enough to use all its little tricks, but we do like trying. Good job old bean. Yours, R.E.A. III #80888

RONSIM 01-25-2017 07:55 AM

Thanks for the post! It took a lot of work to put it together!
Much appreciated, and, as I am attempting to decide which 10" screen I am going to put in my -6A, I was interested in your assessment of the Garmin product.


vic syracuse 01-25-2017 08:00 AM

Very nicely organized, Katie! The only thing I would encourage you to consider would be to put that fuse block on a swing down panel.


Chkaharyer99 01-25-2017 08:51 AM


Thanks for sharing your rationale for deciding on Garmin. Your pictures and mock up are great.

KatieB 01-25-2017 09:04 AM


Originally Posted by vic syracuse (Post 1144665)
Very nicely organized, Katie! The only thing I would encourage you to consider would be to put that fuse block on a swing down panel.


Thanks, Vic! Have you ever heard of a problem with a fold-down fuse panel being secured upside-down in an airplane? Do the fuses ever vibrate out? I'm planning to use fuses for the lighting and other non-essential items.

vic syracuse 01-25-2017 09:19 AM

Well considering you might be doing aerobatics in the 3 the g-forces might cause them to loosen if they were upside down, but you could easily secure them with a single strand of safety wire across the top of each row. The reality is that they would probably be OK, and if they are for nonessential items, then just checking them for security once in a while should suffice.


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