Position of Autopilot control

WDD

Final Approach
PoA Supporter
Joined
Oct 16, 2019
Messages
6,089
Location
Atlanta / Marietta
Display Name

Display name:
Vintage Snazzy (so my adult children say)
Scheduled for October/November installation. Nothing to do in the meantime except play around with the configuration.

How high should the autopilot control be in the center stack? Lower?
Do I have any use for the old mechanical CDI, as it would be only showing VOR/ILS, and that is already going to be shown on new GI 275

1722965493641.png
 
I’d want it lower so my hand doesn’t cover the two MFD’s when I’m manipulating it. I would put the A/P right above the transponder and move the MFD’s up.
 
What products are C1/N1 and C2/N2?

I would likely remove the CDI.

I would likely put the AP control head at the top of the stack, the comm panel next, then the two Garmins and the transponder at the bottom, especially if it’s controlled by one of the other Garmins.

I could make a case for AP, C1/N1, C2/N2, Comm Panel, Transponder from top to bottom on the center stack.
 
What products are C1/N1 and C2/N2?

Com 1/Nav 1 will be a GTN 650xi. Com 2 will be from the current GNC 355. No Nav 2.

Audio panels are usually at the top, but I can’t tell you why. And I see autopilots usually at the bottom, but again I can’t tell you why that’s the best place.

The transponder is the least interacted with, so I can see putting that at the bottom or even on the right side if space is needed.
 
Last edited:
My vote:
Just like it is, except move the AP down right above the transponder. That puts the top C1/N1 screen level with the top 275 (personal preference).
CDI is optional. But could come in handy if you lose GPS, the HSI, and are IMC all at the same time ;)

Just curious..is the audio a PAR200B?
 
Audio will be a PMA 450C. PAR200B can’t handle two additional coms (new GRN and current GNC) nor do I need a total of three coms.
CDI is optional. But could come in handy if you lose GPS, the HSI, and are IMC all at the same time ;)
That ……….. would be a bad day indeed.
 
I'd put it wherever it's easiest and most natural to reach.
 
I'm so rusty I'd have to give this more thought
but my initial thoughts are
I feel like I'd want to autopilot at the bottom for easier reach from the throttle
I'd want my radios with displays up high because I'm looking at them more often, don't want to look down
Intercoms are almost always at the top in my experience. I don't know why but I guess it makes sense
transponder is infrequent so don't need to reach it often form the throttle and it also don't need to be eye level

Top to bottom, I think I'd go
intercom
navcom
navcom
transponder
gps
 
Autopilot is a flight control, so should be close to other flight controls, i.e. throttle/prop/mixture. GPS is a visual device so should be closer line of sight. Thus, I would stack it as:
Intercom
GTN650xi
GNC355
Transponder
GFC500

If the CDI is composite input, I would delete it in favor of the GI275 HSI
 
…Audio panels are usually at the top, but I can’t tell you why. And I see autopilots usually at the bottom, but again I can’t tell you why that’s the best place…
Tradition and history are often hard to overcome. One thing I came across lately while researching EFIS panel layouts was AC23.1311. While it is particular to part 23 aircraft there is a good discussion on location of various things relative to eye position.

AC 23.1311-1C - Installation of Electronic Display in Part 23 Airplanes https://www.faa.gov/regulations_pol...fm/go/document.information/documentID/1019680

The info in Table 3 has really changed my mind about center stack layout in a retrofit glass cockpit. From my perspective, putting the GFC500 at the top with the GTN directly below it puts your PFD, HSI, Navigator display and AP control at relatively the same plane for your instrument scan and operation. It also keeps your hands farther away from the T/P/M when manipulating the GFC, lessening the (low) chance of inadvertently making a change to those controls.

OTOH, the audio panel doesn’t usually get much use except to toggle Comm 2 when it’s needed and to get the visual marker indications to back up the audio.

There’s probably holes in my thought process but looking at most modern part 25 panels, the AP mode control panel is usually directly above the PFD, so there is probably some confirmation bias in my thought process.

But it’s your plane; do what your budget allows and satisfy your wants.
 
OTOH, the audio panel doesn’t usually get much use except to toggle Comm 2 when it’s needed and to get the visual marker indications to back up the audio.
What's a "marker"? :)
 
What's a "marker"? :)

Seriously? It’s the blue, yellow, and white indicator lights with O, M, and I on them that light up when you over fly the marker beacon on certain instrument approaches. The outer marker is glidelsope intercept or Final Approach Fix, the Middle is decision height, the white is the same for a Cat II ILS.
 
Seriously? It’s the blue, yellow, and white indicator lights with O, M, and I on them that light up when you over fly the marker beacon on certain instrument approaches. The outer marker is glidelsope intercept or Final Approach Fix, the Middle is decision height, the white is the same for a Cat II ILS.
I've flown plenty of ILS approaches and never see them light up. They could just simply be decals for all I know.

(yes, I'm being facetious but not not far from the truth because a whole lot of them near me have been decommissioned).
 
I get pretty surprised when mine goes off. Never used it for it's intended use. (marker beacon)
 
I've flown plenty of ILS approaches and never see them light up. They could just simply be decals for all I know.

(yes, I'm being facetious but not not far from the truth because a whole lot of them near me have been decommissioned).

I hear you. Locator Outer Markers being decommissioned is part of the MON plan. There’s still an active LOM at HYI on the ILS or LOC 13. The IM at SAT was decommissioned last month.

There’s an LOM charted at CLL that’s been notam’d out of service since Christmas.
 
I put my autopilot on the top of the stack because I like the easy access to the physical buttons for changing heading and altitude bugs ... even though I'm mainly flying manually. This works well because I have toggles on my stick grip to flip COM1 active/standby, COM2 active/standby and COM1/COM2. So I don't need to actually touch the audio panel as often.
 
Of the planes I have flown, most seem to follow this layout:

Audio panel
Com/Nav1
Com/Nav2
Xpndr
Autopilot

(unless the A/P display was hard to read, needing you to duck your head to see it for some reason then I'd put it above the xpndr)

edit;
Oh, and keep the ‘spare’ cdi.
 
Last edited:
The three things you touch the most, and need to find quickly "in the heat of battle", are the throttle, autopilot, and navigator. Put them as close together as possible.
 
I prefer it lower in the stack.
Nice layout. 1) Why do you prefer the autopilot at the lowest position? 2) Do you ever use your mechanical CDI? 3) Curious - what do you do with the third GI 275 on the right panel that is a second AHRS? Instructing?
 
Do I have any use for the old mechanical CDI, as it would be only showing VOR/ILS, and that is already going to be shown on new GI 275
What make/model is the CDI? Is it currently connected to the GNC355? Have you flown an approach with it yet?
 
It’s a Bendix King. It is currently connected to the GNC355 (GPS, no Nav radio is in the airplane).IMG_0251.jpeg
 
I'm guessing it's got a NAV converter and runs off of a composite interface rather than a resolver. I'd dump it fly the HSI.
 
I’ll have to read up to understand exactly what you said -
I did pick up “dump it”. Thanks / appreciate it.
 
Airline guys like teh AP controller at the top of the stack, as that is what they are used to.

I recently did my panel in my Mooney and put it to the left of the stack just over the throttle. It works well there for me.

IMG_2745.JPG
 
I’ll have to read up to understand exactly what you said -
I did pick up “dump it”. Thanks / appreciate it.

Bottom line is you’ll have to pick and choose which GPS would display on the separate CDI. The reason to keep it is if you think the HSI and PFD will both fail.

The reason to dump it is knowing that if both the PFD and HSI fail there’s probably not enough electrical power left to drive the second GPS and CDI.
 
Nice layout. 1) Why do you prefer the autopilot at the lowest position? 2) Do you ever use your mechanical CDI? 3) Curious - what do you do with the third GI 275 on the right panel that is a second AHRS? Instructing?

Autopilot at the bottom puts things with visual interest closer to my eye level.
Haven't had the new gear in long enough to use the NAV2 indicator yet. (I'm thinking about swapping it out for a fourth 275.)
Unless I'm flying IFR, I tend to fly from the right seat. The 275 puts everything right in front of me.
 
Autopilot
GPS
GPS/Com 2
Transponder
Audio panel

The Cessna factory had it as:
* Audio panel​
* GPS​
* NAV/COM​
* NAV/COM​
* Transponder​
* Autopilot​

...for so long on so many planes that someone is bound to complain that you got it backwards.

EDIT: Seems most sims are set up that way too.
 
Last edited:
I would put AP below any touch screens to prevent inadvertent touches.
 
  • Like
Reactions: WDD
I have a 182. Ap at bottom. I really wish it was at the top
 
I use it way more than the Audio Panel.
Better in the scan high. It's just Mt opinion, but I flew a 182 with it on top. It was WAY easier and convenient
 
  • Like
Reactions: WDD
I kept the old CDI for Nav2. I find that changing the display on a -275 from one setting to another troublesome. Particularly in even light turbulence. It is a very small virtual button that it easy to miss or double tap when the plane is bumping along. I also find it inconvenient to change the VOR course on the -275 HSI as it requires tapping another of the tiny virtual screen buttons to select Course, and then turning the knob to set the course. I find it much easier to fly an VOR radial or setting a crossing radial on Nav2 using the legacy CDI.
 
Back
Top