J

John-G

Well Known Member
Now that Van?s has begun offering the new Dynon SV-AP-PANEL and SV-KNOB PANEL (autopilot control panel and dedicated knob control panel respectfully) for the RV-12 ? can anybody with hands on experience with these units answer the following question?

Question: For those who have flown with the new autopilot panel installed in the RV-12, are both the instrument panel mounted trim switch AND the trim switch on the autopilot panel functional? I?m assuming they would both be functional based on Van?s schematic drawing and Dynon?s published manuals but would like to verify that.

Because Dynon support participates here in the VAF forums, rather than contacting them directly, hoping for a reply from Dynon support to the questions below so other builders can base their decisions accordingly.

It appears to me as though the autopilot panel can act as a smart relay deck since it receives power directly from the RV-12?s trim fuse and has inputs for both pilot and copilot trim switches, plus programmable speed controls. If I?m looking at Van?s wiring and Dynon?s documentation correctly, seems to me as though the autopilot panel would make a very convenient interface for wiring pilot and copilot control stick grips with trim hat switches without any muss or fuss and still leave the panel mounted trim switch fully functional. The documentation seems to suggest the trim up and down inputs to the autopilot panel just require a ground to be active ? and the Dynon documentation says pilot input overrides copilot input ? so isolation and safety is built into the autopilot panel unit.

Seems like this could be a possible good choice for those RV-12 builders that want the autopilot panel and also desire an easy way to wire control stick grips with trim switches on them.

Question: Am I correct on the above assessment or are there other factors that I have overlooked?

Question: Does the autopilot panel also need the knobs panel to be fully functional?

Question: If the autopilot panel can be installed as a stand-alone item but loses some functionality, what is lost or degraded?

Thanks in advance for answers to the above questions or clarifications.
 
well, I have SV with AP with no switch panel. Works fine without it but it is a bit annoying to hold the panel knob to change to the appropriate mode. From the descriptions, if I had a SV TOUCH instead, that problem is almost eliminated. Touch heading and knob changes to heading mode. Touch Altitude and it knob changes to mode to set your new altitude target. Touch BARO and the knob changes to adjust that parameter. Etc Etc. If I had the touch I'm very sure I would not care about the panels at all...

After all, we are not generally programming the RV12 for a complex coupled approach or standard rate descent to meet a specific crossing point... And at 115-120 KT things shouldn't be sneaking up on us...
 
One more question

I hope you don't mind if I add one more question John...

With the presence of the SV-AP-PANEL, does the autopilot automatically run the trim when required for altitude hold or is it still a manual operation?

Alex
 
Alex - I believe I read somewhere where having the autopilot automatically running the trim has been eliminated in the current software version. Apparently that feature has been put on hold for the time being. I may have that wrong but think that is what I remember reading.
 
There are no trim buttons on the AP control panel. The NOSE UP and NOSE DOWN are commands to the AP to initiate altitude changes. While the "relay deck" is inside the panel, the only way to activate it is with external switches. In the RV-12 this is the existing trim switch, and you could also wire this to a stick grip easily.

Auto trim hasn't been "removed" from any software, it just hasn't been released yet. It is planned for the next software update. It will keep the plane in trim for you when the pitch axis is engaged.
 
In the RV-12 this is the existing trim switch, and you could also wire this to a stick grip easily.
Click to expand...

How to protect a short, when momentary trim switches are installed on both stick grips and my Co. is accidently pushing trim DN while I am activating trim UP at the same time?
 
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Thanks

Dynon Support - thank you for the clarification regarding the nose up and down switches on the autopilot panel.

Chris- The Dynon documentation for the autopilot panel states there are two separate trim inputs for nose up and nose down trim. One is for the pilot (where the current Van's drawing shows the panel mounted trim switch connected) and the other is the copilot. The Dynon documentation states the pilot's trim inputs will override the copilot inputs which should address your question.

Below is the text from the Dynon documentation.

"Integrated Trim Control Operation
The SV-AP-PANEL has an integrated two channel trim controller that can be used instead of the normal relay decks that would nominally installed. It is connected to your trim motor(s) (usually pitch, and sometimes roll or rudder, dependent on the aircraft). It control inputs are normally wired to the pilot and/or copilot sticks or switches on the panel. When you press and hold the button or switch corresponding to the trim direction requested, the trim motor moves in that direction.

Speed Scheduling
When configured, the trim controller's adjustable speed scheduling capability may be set to slow down the speed of your trim motors as you fly faster so that your trim sensitivity is the same across your airspeed ranges. This behavior is configured during installation.

Trim Controller Safety Features
Controlling aircraft trim in your aircraft is serious. The SV-AP-PANEL's integrated trim controller features the following safety features:
* When the trim controller is connected to two sets of switches or stick controls, one of them will always take priority over the other when the requested trim commands disagree. This is normally the "pilot" position, but whether or not this is the left or right seat or set of controls will vary by aircraft.
* Although hosed in the SV-AP-PANEL, the electronics in the trim controller are powered by aircraft power and are independent from SkyView. Trim control will remain available even if SkyView itself is unpowered or offline. In this failsafe condition, the trim controller's speed scheduling is disabled and the trim motors will run at their full speed when trim is commanded.
* To protect from a "runaway" trim condition, the longest that a trim motor will run continuously even when a trim button or switched is continually depressed is five seconds. After three seconds, the trim motor will cease responding until the trim button is released and pressed again."
 
John-G said:
The Dynon documentation states the pilot's trim inputs will override the copilot inputs which should address your question.
Click to expand...

Interesting and good to know. I wonder if the priority switch can be switched? I always fly my airplane from the right seat, even when solo. I just do. It would be nice to let a person flying in the left seat have pilot authority but normally I would want it. I wonder if a toggle switch would let one select right or left seat control.
 
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