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PhatRV
07-15-2020, 09:16 PM
I am installing the Dynon servo in my RV8. I am at the point in the instructions that has the “disengage CWS” wiring diagram.

Is this the same as to disengage the autopilot?

How is the “disengage CWS” button used during a flight in a small airplane like the RV8?

Thanks

BillL
07-15-2020, 09:39 PM
I am installing the Dynon servo in my RV8. I am at the point in the instructions that has the “disengage CWS” wiring diagram.

Is this the same as to disengage the autopilot?

How is the “disengage CWS” button used during a flight in a small airplane like the RV8?

Thanks

If it is like the Garmin... it should be disconnect / CWS. Press for one second=disengage, and three seconds = CWS - Dynon may be different.

RV8JD
07-15-2020, 11:07 PM
Dynon works a little differently. A single press of the Disconnect/CWS switch disconnects the AP. Press and hold the Disconnect/CWS switch while the AP is engaged puts the AP into the CWS mode, and the AP servos are temporarily disengaged. This lets you fly the airplane by hand for short periods to make an adjustment to the AP's targets without completely disengaging the AP. Release the switch and you're back in full AP mode.

Take a look at the SkyView Classic/Touch Pilot's User Guide starting on page 8-11 to see how the AP targets are adjusted for the "Simplified AP Mode" and the "Expert AP Mode" when the switch is released and CWS mode is disengaged.

You can also configure the Disconnect/CWS switch to engage the AP by holding the switch/button for a few seconds and then releasing the button when the "REL TO ENG" annunciation comes up in the Top Bar. I have this function enabled and like it.

Very useful functions for a button on the stick grip.

PhatRV
07-16-2020, 08:48 AM
Dynon works a little differently. A single press of the Disconnect/CWS switch disconnects the AP. Press and hold the Disconnect/CWS switch while the AP is engaged puts the AP into the CWS mode, and the AP servos are temporarily disengaged. This lets you fly the airplane by hand for short periods to make an adjustment to the AP's targets without completely disengaging the AP. Release the switch and you're back in full AP mode.

Take a look at the SkyView Classic/Touch Pilot's User Guide starting on page 8-11 to see how the AP targets are adjusted for the "Simplified AP Mode" and the "Expert AP Mode" when the switch is released and CWS mode is disengaged.

You can also configure the Disconnect/CWS switch to engage the AP by holding the switch/button for a few seconds and then releasing the button when the "REL TO ENG" annunciation comes up in the Top Bar. I have this function enabled and like it.

Very useful functions for a button on the stick grip.

Thanks for the explanation. Is it then normal to have two switches on the stick?
1) Disengage/CWS
2) Disconnect AP.

I was reading the manual and I thought the AP can be disabled on the screen but I think having a separate disconnect AP on the stick is also helpful.

FinnFlyer
07-16-2020, 09:35 AM
Thanks for the explanation. Is it then normal to have two switches on the stick?
1) Disengage/CWS
2) Disconnect AP.

I was reading the manual and I thought the AP can be disabled on the screen but I think having a separate disconnect AP on the stick is also helpful.

I thought there is only one input for this? So only one switch on the stick (of course you can parallel other switches located elsewhere, but they will all have the same functions)

CWS: ControlWheel Steering

Finn

SPX
07-16-2020, 09:40 AM
Thanks for the explanation. Is it then normal to have two switches on the stick?
1) Disengage/CWS
2) Disconnect AP.

I was reading the manual and I thought the AP can be disabled on the screen but I think having a separate disconnect AP on the stick is also helpful.

If you are installing AFS avionics using the Dynon Servos (and maybe this is true for Dynon avionics as well) you need a disconnect AP button, and not just rely on being able to do so on screen, to be able to get through the autopilot configuration test before the autopilot is used for the first time.

RV8JD
07-16-2020, 11:51 AM
Thanks for the explanation. Is it then normal to have two switches on the stick?
1) Disengage/CWS
2) Disconnect AP.

I was reading the manual and I thought the AP can be disabled on the screen but I think having a separate disconnect AP on the stick is also helpful.

No, only one switch or button on the stick is needed to control the three functions:

- AP Disconnect - a single press of the Disconnect/CWS switch disconnects the AP.

- Press and hold the Disconnect/CWS switch while the AP is engaged puts the AP into the CWS mode, and the AP servos are temporarily disengaged. This lets you fly the airplane by hand for short periods to make an adjustment to the AP's targets without completely disengaging the AP. Release the switch and you're back in full AP mode.

- You can also configure the Disconnect/CWS switch to engage the AP by holding the switch for a few seconds and then releasing the switch when the "REL TO ENG" annunciation comes up in the Top Bar.


On my RV-8 with the Infinity stick grip, I have the top left button (the red one in the pic below) as the Disconnect/CWS switch (with the three functions enabled).

275

Yes, the AP can always be disengaged via the screen. Some builders have put the physical Disconnect/CWS button on the panel, but a button on the stick (instead of the panel) is very useful. There should also be a switch on the panel that cuts electrical power to the servos as a fail-safe way to disconnect the AP in an emergency if the AP disconnect button does not work.

Hope that helps,

PhatRV
07-16-2020, 09:39 PM
I have an Infitity stick but it has the flap switch. I am going to mount the Disconnect/CWS by the thumb switch in the arrow below. Thanks for all the help.

riseric
07-17-2020, 07:38 AM
I have an Infitity stick but it has the flap switch. I am going to mount the Disconnect/CWS by the thumb switch in the arrow below. Thanks for all the help.
I presume your stick has a Normally Open, Momentary switch there?

I have the Infinity also (no flap switch) and mine is a Push On-Push Off type at that location...

Dgamble
07-17-2020, 10:27 AM
I am installing the Dynon servo in my RV8. I am at the point in the instructions that has the “disengage CWS” wiring diagram.

Is this the same as to disengage the autopilot?

How is the “disengage CWS” button used during a flight in a small airplane like the RV8?

ThanksIf your question is “what would I use CWS for in a small plane,” I use it when I want to orbit a site on the ground for photography or the like. With the AP set for straight and level flight, I will engage CWS and roll the plane into the bank angle I want. With my Skyview, that means hold the AP disconnect button until it changes to CWS mode, roll the plane into the bank angle I want, then release the button. It will hold that angle and altitude until I change it back by pressing the “Level” button.

PhatRV
07-18-2020, 10:28 AM
I presume your stick has a Normally Open, Momentary switch there?

I have the Infinity also (no flap switch) and mine is a Push On-Push Off type at that location...

Good point. I have to check to make sure it’s momentary on