Van's Air Force
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GRT panel control of remote nav/com
- Thread starter von_flyer
- Start date
Isaac
Well Known Member
RE: GRT Remote Tuning
GRT has a doc on their website that describes the buttonology for using the remote avionics funtions. The screen shots are for the new Hxr versions with dedicated buttons and knobs specifically implemented for remote avionics control. The Hx and Sx EFIS will interface and control a remote Trig xpndr but the menus etc are different as the older units don't have the dedicated button and knobs for controlling remote avionics.
http://grtavionics.com/media/Remote-Avionics-Controls.pdf
I have the GRT Sport HS EFIS. The Sport HS doesn't have the ability to control remote avionics but I find that it it is easy to use the basic functions even in turbulence so would expect that controlling remote avionics would be similar.
GRT has a doc on their website that describes the buttonology for using the remote avionics funtions. The screen shots are for the new Hxr versions with dedicated buttons and knobs specifically implemented for remote avionics control. The Hx and Sx EFIS will interface and control a remote Trig xpndr but the menus etc are different as the older units don't have the dedicated button and knobs for controlling remote avionics.
http://grtavionics.com/media/Remote-Avionics-Controls.pdf
I have the GRT Sport HS EFIS. The Sport HS doesn't have the ability to control remote avionics but I find that it it is easy to use the basic functions even in turbulence so would expect that controlling remote avionics would be similar.
Jvon811
Well Known Member
Anything else??
Anyone have pics of using a GRT Sport EX to control remote mounted avionics? I'm thinking about making a very clean panel for my RV-4 with one Sport EX on the panel and everything else remote mounted. I've seen the information that was posted above, but it's hard to find anything about the other GRT EFIS' controlling avionics.
-Justin
Anyone have pics of using a GRT Sport EX to control remote mounted avionics? I'm thinking about making a very clean panel for my RV-4 with one Sport EX on the panel and everything else remote mounted. I've seen the information that was posted above, but it's hard to find anything about the other GRT EFIS' controlling avionics.
-Justin
This would be a large single point failure mode, of course - lose the efis, lose all avionics. I guess okay for vfr at non - tower airports.
IMHO you really want a large efis (HXr) with dedicated buttons/knobs for remote avionics. I have an HX with a remote Trig transponder, and re-setting the squawk code involves a few button pushes and knob turning. Okay for squawk code, which doesn't get changed that often. But my home tower frequently asks for an ident, often enough that I brought a remote ident wire out to a button on my stick grip.
Canadian_JOY
Well Known Member
Hmmm... I thought I was a square peg in a round hole when I installed the Trig TC20 control head rather than controlling the TT22 from either the HX or Mini-X. My thinking, and it was only thinking since I still haven't flown behind this instrument panel, closely mirrored yours, Bob. Thanks for confirming the aspects of EFIS-related workload associated with remote transponder operation.
An added benefit of installing the TC20 control head is that it is also a TSO'd altitude encoder for the TT22 transponder. Some avionics shops give grief when using an EFIS as the encoder source - the TC20 takes that argument off the table. The "reported Flight Level" readout on the TC20 display is a nice feature that allows one to always see the altitude being broadcast, and can even, in a pinch, work as a 100 foot Pressure Altitude altimeter should one's primary altimeter fail. Just remember it's in 100 foot increments, and it's altitude relative to 29.92" pressure setting.
I have heard getting the non TSO encoder approved can be an issue for Canadians. But I have not heard of any US installations being given grief. I let the GRT EFIS control the Trig mainly because it then also controlled the (US only) required air-ground switching for adsb-out. To stand-alone I would have needed to install a switch in the pitot line.
Canadian_JOY
Well Known Member
Interesting perspective, Bob. When I contacted Trig and asked specifically about the air/ground transition and the need for a squat switch, this was the response I received.
"You only need a second air/ground determination solution if you use an ADC, because apparently they are too unreliable. So using GPS ground speed alone is actually ok."
With this information in hand I believe the air/ground switch (either a squat switch or an airspeed switch) is unnecessary. I would happily learn from others who have gone down this path before and have real-world experience. OK, maybe I wouldn't be so happy if I were to discover I really do need to install an airspeed switch...
"You only need a second air/ground determination solution if you use an ADC, because apparently they are too unreliable. So using GPS ground speed alone is actually ok."
With this information in hand I believe the air/ground switch (either a squat switch or an airspeed switch) is unnecessary. I would happily learn from others who have gone down this path before and have real-world experience. OK, maybe I wouldn't be so happy if I were to discover I really do need to install an airspeed switch...
I honestly don't recall where I read about the airspeed switch accessory being 'required' for stand-alone adsb operation. It was over a year ago. I will relate my experience with the FAA's automated adsb test. Originally I think GRT fixed the change over speeds at 35 knots. I kept failing the FAA test, since I was in the habit of taking it easy on the brakes. Apparently I was letting it roll on the runway too long/too fast, and I kept failing the 'air/ground' part of the test. When I firmly braked to a complete stop immediately after touchdown, I passed the test. Now, GRT's latest software looks at both airspeed and gps ground speed, with adjustable limits. I set the indicated airspeed change over at 50 kias, and have not had problems with the automated test since then.
I have the HXr with a remote trig transponder. Changing squawk is easy and couldn't see a benefit to a dedicated/redundant interface. I also have a remote ident on the grip. I also had an SL-30 interfaced to it early on. Honestly, I never used the HXr to tune or swap a frequency. It was more natural and intuitive to just tune it on the radio itself (it's only 8 inches away). I don't think that I ever pushed a frequency to it either. I tend to use the ipad/FF to get frequencies instead of the GRT. It is a bit easier to tune a freq on the HXr, with the button pad, but I just never got around to making it a habit.
Given that I fly in IMC, I would not be be comfortable without at least one radio that could be manual tuned from the radio itself.
Larry
Given that I fly in IMC, I would not be be comfortable without at least one radio that could be manual tuned from the radio itself.
Larry
