The instrument panel is probably the area where individual builders have the best chance to customize the aircraft to fit their approach to flying (and their budget). I've looked at a lot of other RV panels, searching for good and bad ideas. I have flown a fair number of different types and classes of aircraft, so I have seen quite a few different approaches. You can see a larger version of the instrument panel image in my Construction Photo Gallery.


I've been fiddling around with ideas for my instrument panel for about two years now. I've been messing around on my laptop when I was on the road, and trying things out with a plywood mock-up covered in Velcro when I was home. I thought I had come up with a pretty good layout a few times, but I've always found a weakness after I ponder it for a few weeks. I think I'm finally zeroing in on a final design. The main elements of my proposed panel haven't changed for about a year now, and the details that I'm messing around with are getting smaller and smaller. I still have to get correct dimensions for a few items, so I guess I may have to still make a few adjustments if I get a nasty surprise in this area.

I'm going to have a "Standard-T" flight instrument layout, as that is what I've flown with pretty much every flight since I left the military (some of the old military stuff I flew had more random layouts). I'm putting the avionics stack on the left side, as I'll be flying with the stick in my right hand, which leaves the left hand to fiddle with the radios. I'm hoping to buy a Garmin GNS-430 GPS/NAV/COM as my primary set of radios. The GNS-430 is still fairly expensive, but the price isn't so bad if you compare it against the cost to purchase separate approach approved GPS + NAV + Glide Slope + COM. And it takes up a lot less room on the panel than three separate boxes. And it gives a fairly nice moving map display. It can also serve as the display for a StormScope, should I later decide to install one. I'll use a Microair 760 for my second com radio, as it is very reasonably priced, has a great reputation for quality, and doesn't take up much room.

I'm using old-fashioned round dial tachometer and manifold pressure gauges, as they provide the best "at a glance" information. All the other engine parametres will be displayed on a Grand Rapids EIS The EIS doesn't have the greatest display formats, but you can set upper and lower limits on every parametre. If any parametre goes out of limits, a big red light flashes to catch your attention, and the display changes to show the offending parametre, with a label saying what it is. That means I don't have to actively monitor the other engine indications, so the cruddy display format doesn't matter too much.

The instrument panel is in three pieces - the main central part of the panel, plus a small sub-panel on each side. The sub-panels will be permanently installed and the main panel will be removable. I'll cheat a bit and shave 1/8 inch off the edge of the inboard edge of the left sub-panel so I can keep the flight instruments as close as possible to the centre of the panel (idea stolen from Greg Hale).


Left Sub-Panel

I've got four switches on the bottom of the left sub-panel. The switches for the magneto (left ignition system) and Light Speed electronic ignition (right ignition system) are outboard. Next is the Start Enable. I've got a fuel injected engine, and they can be a bear to start when the engine is hot in my experience. You often have to start a hot engine with the throttle wide open, and close the throttle after the engine starts. I want to be able to hold the stick back with one hand, and have the other hand on the throttle, which means I'll have a start switch on my Infinity stick grip. I don't want to accidentally hit the start switch when the engine is running, so I've added a separate Start Enable switch, which I'll flip just before starting, and turn it off afterwards. This switch has a momentary full up position, which also engages the starter. This is in case the start switch on the stick dies. The Start Enable switch is guarded, because the next switch over is the flap switch, which will be used a lot. If the Start Enable switch wasn't guarded, there would be a risk of accidentally hitting the starter when I wanted to raise the flaps. The throttle quadrant is just a few inches below the left sub-panel, so I can just reach up with a finger to move the flap switch.


Right Sub-Panel

Originally, I planned on having the landing light switch on the very back end of the row of switches on the right console (not shown). I figured I would be able to quickly find it by feel, turn it on when flying at night. Well, yesterday I finally put the *censored*pit floors and seat backs in again, and spent some time sitting in the *censored*pit, using a couple of folded blankets as seat cushions. I discovered that it was difficult to reach the aft end of the right console. If I juggled the order of switches, so put the landing light switch further forward, I wouldn't be able to find it without looking. So, I decided to move the external light switches to the bottom of the right sub-panel.

The most inboard switch on the right sub-panel is for the navigation lights and strobe lights. The upper position selects both navigation lights and strobe lights. Sometimes when flying in cloud at night the reflections from the strobe lights can become very distracting, so the middle position gives nav lights only.

I'll be using a couple of simple flood lights to light the panel for the rare occasions when I'll fly at night. I've got a map night on a goose-neck that I'll mount on the right side-wall of the *censored*pit. It'll also serve as my emergency flood light in case my main flood lights die.

I need to start cutting holes in my instrument panel soon, so I've been messing around trying to finalize the design. I need to start running the wires for the engine instruments, but I can't do that until I get the instruments in the panel. I know where the engine instruments will be, within about an inch. I decided to cut some holes in a plywood mock-up to hold the engine instruments until I nail down exactly where they need to go. That last inch I need to sort out won't affect the wiring, so this will let me make progress. I can't really nail down the exact location of everything until I get the racks that my avionics will mount in. I'm trying to push everything as far left as I can, and the fit of the racks will determine where the rest of the stuff ends up.

This week I installed the exhaust gas temperature (EGT) probes. It took a lot of measuring to figure out where to mount the probes. They all should be the same distance from the end of the exhaust pipe, not on a curve, and not on a weld. Of course every pipe has its curves and welds in a different place, so it was a real trick to find a suitable location. I finally settled on a distance of 4 13/16 from the end. Then I had to sort out what angle to have the probes come out, so they wouldn't hit anything, or get in the way of changing spark plugs. I really gritted my teeth when I drilled the holes, because the exhaust system is pretty expensive, but it all worked out OK.

Yesterday I drilled all the holes and installed the platenuts for the various stainless steel shields that protect the rubber grommets where cables, wires, etc come through the firewall. Today I ran the cylinder head temperature and EGT wires from the EIS-4000 engine monitor though the firewall, and connected them up to the probes. I used a heat gun on each probe to make sure it worked, and that I had it wired to the correct cylinder. So far , so good.