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Panel Layout

thompsonbr87

Well Known Member
Looking for opinions on my panel layout. What does/doesn't work physically? Ergonomically? Anything in particular to watch out for? 6A-Slider

Shout out to eHangar.org for their panel design tool.

Across the bottom, switches are:
(3) Battery, Alternator, Emag
(4) Lights - Panel, Nav, Landing, Strobes. Any suggestion on the order of these?
(1) Pitot heat
(2) Avionics, Turn Coordinator (S-Tec 30 - Does it need a dedicated switch? Just copying what already in the plane for now)

The two switches above the S-Tec 30 are Autopilot, and the 2nd is actually a button for Alt Hold (eHangar doesn't have momentary push button).

The vertical switches above the throttle are fuel pump on top, flaps on bottom.

Push/pull knobs between mixture and circuit breakers are both cabin heat. (One on each side. Should I ditch that set-up and just have one control?)

32znbxw.jpg
 
may want to move ignition switch

Main thing I would reconsider is the location of the ignition switch since most of us have more than a single key on the "ring". In rough air those keys would be bouncing around on the instrument panel possibly scratching the finish.

Consider relocating to the lower left just above the air vent.
 
If it were me, I would arrange the instruments in a standard 6-pac.(alt and vert on the right and the ball in lower left)
I would not stack my fuel pump and flaps. Having them near the throttle is good.
I would move the USB ports lower and not have them over any switch. Cables will be in the way.
Agree, the key switch should be lower and not above a switch. You will most likely have the plane key on a key ring.
You only need one cabin heat knob for a -6
But you will need carb heat if you have a carb. It should be near the throttle or center area.
I found the fan library useful.
https://www.faa.gov/documentLibrary/media/Advisory_Circular/AC_23_1311-1C.pdf
 
If (when) you need to do maintenance on or behind the panel, you're going to dog-cuss the guy that put all the switches, and even more importantly, the engine controls, through the panel with no way to separate them from the panel when you pull the panel out of the plane. And if you don't leave service loops & install panel wiring disconnects, you'll likely go after him with a gun.

Take it from someone who's currently working behind a panel that *doesn't* have those features.

You may have already made an informed decision, but just in case: An automotive style fuse block using ATC style fuses would cost about the same as one or two a/c circuit breakers, weigh a lot less, be arguably more reliable, and would free up a lot of panel space. The only circuit protection you really need access to while in flight is the alternator field CB (and that, only due to the possibility of a nuisance trip from an overvoltage protection module). Any other circuit, if critical to flight, should have a backup system so that the pilot isn't tempted to troubleshoot instead of flying the plane.

Charlie
 
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If (when) you need to do maintenance on or behind the panel, you're going to dog-cuss the guy that put all the switches, and even more importantly, the engine controls, through the panel with no way to separate them from the panel when you pull the panel out of the plane. And if you don't leave service loops & install panel wiring disconnects, you'll likely go after him with a gun.

This is great advice! I planned this into my panel with the requirement that I can take the whole panel out of the plane in 10 mins. I connectorized all the electricals. Pull the connectors, disconnect pitot lines, pull out a bunch of screws, disconnect vent SCAT tubes, and the panel lifts right out. Here's my electrical disconnect:

i-J9M976k-M.jpg


You may have already made an informed decision, but just in case: An automotive style fuse block using ATC style fuses would cost about the same as one or two a/c circuit breakers, weigh a lot less, be arguably more reliable, and would free up a lot of panel space. The only circuit protection you really need access to while in flight is the alternator field CB (and that, only due to the possibility of a nuisance trip from an overvoltage protection module). Any other circuit, if critical to flight, should have a backup system so that the pilot isn't tempted to troubleshoot instead of flying the plane.

Also, great advice! I did this and had lots of room behind the panel (the electronics boxes go on firewall side of the subpanel on an avionics plate.)

i-rSPXL7n-M.jpg


Good suggestion about the breaker for the Alt Field ... I didn't do this; gotta look into it!
 
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Thanks, folks! A couple of "duh" items in there, several that I never would've thought of!

Main thing I would reconsider is the location of the ignition switch since most of us have more than a single key on the "ring". In rough air those keys would be bouncing around on the instrument panel possibly scratching the finish.

Consider relocating to the lower left just above the air vent.
Seems to be a common suggestion. :)

If it were me, I would arrange the instruments in a standard 6-pac.(alt and vert on the right and the ball in lower left)
I've been playing around with the instrument layout. I actually have an iteration saved laid out similar to what you describe. The turn & slip and autopilot (STec System 30) are one unit. I liked the idea of having a/p front and center a little more than having my backup alt/vsi in a more standard location.

I would move the USB ports lower and not have them over any switch. Cables will be in the way.
I had that thought, but my brain liked the symmetry of the USB ports. I guess they could still be symmetrical in a better location.
You only need one cabin heat knob for a -6
But you will need carb heat if you have a carb.
I'll check the plans and see how this is supposed to be done. Right now, I've got a cabin heat duct on either side of the firewall with the separate controls for each. No carb for me to heat.

If (when) you need to do maintenance on or behind the panel, you're going to dog-cuss the guy that put all the switches, and even more importantly, the engine controls, through the panel with no way to separate them from the panel when you pull the panel out of the plane. And if you don't leave service loops & install panel wiring disconnects, you'll likely go after him with a gun.
I think I understand this bit of wisdom. Removing the panel would require disconnecting every switch. Something a bit like this with controls & switches on a separate panel like below? (Engine controls are currently on a vertical center post per plans).
IMG_0322s.jpg


You may have already made an informed decision, but just in case: An automotive style fuse block using ATC style fuses would cost about the same as one or two a/c circuit breakers, weigh a lot less, be arguably more reliable, and would free up a lot of panel space.
I've got either 6 or 7 CBs right now. Just put an array in as a placeholder since I wasn't sure exactly how many I would need. I do like the idea of the fuse block. Will certainly continue to make things look cleaner. I guess instead of a popped CB, you just know something has happened when a component doesn't work?

This is great advice! I planned this into my panel with the requirement that I can take the whole panel out of the plane in 10 mins. I connectorized all the electricals. Pull the connectors, disconnect pitot lines, pull out a bunch of screws, disconnect vent SCAT tubes, and the panel lifts right out. Here's my electrical disconnect:

i-J9M976k-M.jpg
Interesting idea. So this disconnects everything on the panel from the rest of the airframe? (switches, busses, lights, servos, sticks, headsets....?)
 
I've got my switches set up similar to what you pictured in the 1st pic, with the sub-panel split in 3: left hand switches, engine controls, and right side switches. Left side wires collect to the left side, right to right, & engine controls drop straight down/toward firewall.

If you like the look, or just prefer to preserve your knee room, you can keep the switches/controls in the same place, but cut rectangles out of the instrument panel. The switch subpanels would mount behind the main panel with 4-6 screws & nutplates.

Another option is to put all the power wiring on big multipin connectors as shown in wjb's pic, but I elected to avoid doing that with power distribution for simplicity/reliability (fewer 'joints' in the wire runs), and, well, money. The big multipin connectors that will carry higher current can get pricey. His solution is a lot 'cleaner' when you pull the panel; I just chose the compromise of moving the switch arrays to each side when I need to 'dumpster dive' or pull the panel. Which ever you choose, in my opinion you do want to be able to unplug and take the panel to the bench for any future work, not just on the panel but when doing maintenance to the stuff it hides, like ground buses, rudder pedals/brakes, etc.

I do have a few low-current switches (trim & autopilot disconnect, and some engine control (alt engine) switching) mounted directly to the panel, but those switches do go through subD connectors for easy disconnection for panel removal.

If you can build a modern a/c avionics system with 6 CBs, please teach me. :) One of the great things about ATC fuse panels is that you can isolate almost everything and feed it with its own fuse, without killing panel space (or your wallet). Just find a spot on the subpanel behind the panel, or on a side skin under the panel, or even hinged to the panel or subpanel. Lots of examples here & elsewhere.

Speaking of 'vertical center panels'. If you do that, you'll dog-cuss (or shoot) the builder the 1st time you have to crawl under the panel, too, unless you make it removable/movable. I just spent about 5 hrs under the panel of the -6 I just bought, and the only reason the builder isn't shot is I just can't do the jail time (or find him). Trust me; find another path for the wire that goes from the panel to the rear of the plane. (Cutting the pilot side stick so it's removable like the passenger stick will be a lot easier while building, as well.)

I suspect that you don't have a copy of The Aeroelectric Connection. I strongly recommend purchasing or downloading a (free) copy, and joining the Aeroelectric List email list, before cutting any wire. The author has about 5 decades of experience in everything from exotic military stuff to homebuilts, and wrote the book to help us do things *better* than certified. He participates on that list.

Charlie
 
If you can build a modern a/c avionics system with 6 CBs, please teach me. :) One of the great things about ATC fuse panels is that you can isolate almost everything and feed it with its own fuse, without killing panel space (or your wallet). Just find a spot on the subpanel behind the panel, or on a side skin under the panel, or even hinged to the panel or subpanel. Lots of examples here & elsewhere.

Speaking of 'vertical center panels'. If you do that, you'll dog-cuss (or shoot) the builder the 1st time you have to crawl under the panel, too, unless you make it removable/movable. I just spent about 5 hrs under the panel of the -6 I just bought, and the only reason the builder isn't shot is I just can't do the jail time (or find him). Trust me; find another path for the wire that goes from the panel to the rear of the plane. (Cutting the pilot side stick so it's removable like the passenger stick will be a lot easier while building, as well.)

I suspect that you don't have a copy of The Aeroelectric Connection. I strongly recommend purchasing or downloading a (free) copy, and joining the Aeroelectric List email list, before cutting any wire. The author has about 5 decades of experience in everything from exotic military stuff to homebuilts, and wrote the book to help us do things *better* than certified. He participates on that list.

Charlie

It's a flying aircraft that I didn't build. I quickly realized it needed more circuit protection than it currently has (which is why I stuck those extra CBs on the layout), but I'm definitely being swayed towards a fuse block. I've already been cussing that vertical engine control column and pilot side stick. I reckon I'll be cussing it for a little while longer, anyways. I do have a hard copy of Aeroelectic Connection, and I'm learning a ton from it, but this is my first time going through this sort of stuff, so the curve is a bit steep. At least I enjoy the educational part of the E/AB world!

Anyways, thanks for the tips!
 
This is great advice! I planned this into my panel with the requirement that I can take the whole panel out of the plane in 10 mins. I connectorized all the electricals. Pull the connectors, disconnect pitot lines, pull out a bunch of screws, disconnect vent SCAT tubes, and the panel lifts right out. Here's my electrical disconnect:

i-J9M976k-M.jpg




Also, great advice! I did this and had lots of room behind the panel (the electronics boxes go on firewall side of the subpanel on an avionics plate.)

i-rSPXL7n-M.jpg


Good suggestion about the breaker for the Alt Field ... I didn't do this; gotta look into it!

Please come build my electrical system for me! :) Man, that?s some nice work.
 
Interesting idea. So this disconnects everything on the panel from the rest of the airframe? (switches, busses, lights, servos, sticks, headsets....?)

Pretty much; all the panel electrical goes through these connections. Other connections to the back of the panel are mechanical: pitot/static lines, vent ducts.
 
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