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DickF
06-09-2013, 02:41 PM
I decided to fly a test scenario to see what would happen if the EFIS should "die" while on a flight plan with the AP engaged. I have a single screen AF5600 system, GTN650, and TruTrak DF II VSGV.

When I pulled the appropriate breakers, the AF5600 totally shut down, but the ARinc Interface module, the 650, and the AP were continually powered up. When the AF5600 went down, the AP indicated "GPS Flag" and it went to wing leveler and Alt Hold mode. Is this what should have happened?

Somehow I expected the AP to start talking to the 650 "directly" via the ARinc Interface.

Thanks,
Dick

amekler
06-09-2013, 03:40 PM
Dick,
do you have the AFS AP or the trutrak VSVG.? Anyway you should have a switch where you can have the AP take commands from either the EFIS or the GTN650.
Alan

Rob Hickman
06-10-2013, 11:08 AM
How do you have the AF-Pilot GPS input wired?

DickF
06-11-2013, 06:35 PM
I have a TruTrak DF II VSGV (not AF Pilot).

I followed the diagram as shown on Ver 2.6 pg 166 (which I believe is the same as Ver 2.9 page 193.)

Dick

Rob Hickman
06-12-2013, 08:17 AM
If you have the AP RS-232 input wired to the EFIS and turn off the EFIS it will lose GPS. If you have the AP GPS input wired directly to your GPS it should not lose the GPS when the EFIS is shut down.

brianjohnson
06-14-2013, 05:06 PM
I thought the autopilot had to be wired to the EFIS to control it? Are you suggesting a switch?

Rob Hickman
06-19-2013, 12:03 PM
Only the AF-Pilot has serial control of the AP, with a Digiflight II VSGV it needs to be wired to a GPS.

DickF
06-21-2013, 04:18 PM
I'm confused. Since I had purchased the DF II VSGV prior to deciding on the AF5600, I elected to save the additional costs and not upgrade to the AF-Pilot. So,

1. What is the recommended wiring scheme for an AF5600-ARinc-GTN650-DFII VSGV environment?

2. Assuming the recommendation for a DFII VSGV is different than the corresponding recommendation for an AF-Pilot, what functionality will be lost compared to having the DFII VSGV wired as if it were an AF-Pilot?

3. Is there a compelling argument for me to upgrade to the AF-Pilot?

Thanks
Dick

amekler
06-21-2013, 05:02 PM
dick,
i upgraded from the DFII VSVG to the AF-pilot after talking to trevor at trutrak. this always control through the EFIS.
I've had a few issues but for the most part it works quite well.
alan

DickF
06-21-2013, 07:54 PM
Hi Alan,

I did not identify the "need" to do the upgrade. Could you elorborate a bit as to why you decided to do it?

Also, have you done a "failure mode" test as I described earlier? If so, what happened?

Thanks,
Dick

amekler
06-22-2013, 02:32 AM
dick,
i did the upgrade because i wanted to use the EFIS to control the ap and have more functionality. i would talk to rob or trevor at trutrak. some time ago there was supposed to be a climb/descend speed mode(don't know what happened) I have used the ap in both efis and ap modes but have not tried to see what happens if the efis is shut off. Will do that next flight.

Alan

brianjohnson
06-22-2013, 10:01 AM
The AF pilot is actually cheaper than the VSGV and when coupled with the AFS EFIS it provides some additional capabilities like altitude capture and LOC/ILS. It basically turns your VSGV into a sorcerer with full EFIS integration.

Rob Hickman
06-22-2013, 01:46 PM
The AF-Pilot and Digiflight II VSVG are almost the same. Both units will fly a GPS or ILS approach from the EFIS. The AF-Pilot when wired to an AF-5000 serial port will allow the AF-5000 EFIS to display the current AP status and turn on and OFF the AP from the EFIS screen. When you have the AF-Pilot serial port wired to the EFIS it will be getting the GPS signal from the EFIS. If the EFIS is turned off the AP will not have a GPS signal and will revert to Roll Mode.

DickF
06-22-2013, 06:47 PM
Thanks Rob, I think I now have a better understanding.

I will not be changing anything prior to the trip to Oshkosh so perhaps we can discuss this there.

Dick