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GRT WS to EX Upgrade Questions

Tankerpilot75

Tankerpilot75

Well Known Member
These questions are for those GRT users who have upgraded their old WS system to the newer Horizon EX. Besides a brighter screen, adding synthetic vision and having a faster processor:

1. What other advantages have you seen from the upgrade?

2. Was it difficult to swap out from the WS to the EX from a panel perspective (ie the alignment of the different mounting holes and threading them)?

3. My current gps Comm/navigators are two non-WAAS 430s. They require an ARINC module for EFIS communication which is mounted on the back of the top EFIS. I understand the EX requires a separate ARINC module that doesn’t mount on the EFIS. How difficult was this to wire up and mount? Where did you place the separate module?

Since my panel has two 430s, can I connect both 430s to a new ARINC module and select either one for EFIS use?

4. The old WS does not allow voice warnings to the aircraft intercom and the EX does. What wiring changes did you make to accommodate this capability? I currently have the Garmin 340 system installed.

5. Right now I feed traffic and weather information from my Stratux adsb in receiver to my bottom WS EFIS via hardwire. Traffic does not appear on my top WS EFIS on the PFD display. From the pictures I’ve seen it appears both obstacles and traffic are displayed on the EX PFD page. Does anyone have experience with this?

6. The EX Users Manual says, “ The Horizon EX is intended as a drop-in replacement for the Horizon WS with all the functionality of the WS, plus synthetic vision, a display with four times the resolution, and more. Analog localizer/glideslope inputs are not provided however, although VOR/ILS serial inputs using the SL30 protocol are supported.”

Since I fly ILS approaches does this statement mean that the EX does not support VOR/ILS approaches? This could definitely be a deal killer.

7. The EX Sport (vs the Horizon EX) include’s an internal AHRS unit. While the Horizon EX utilizes an external AHRS. Since my WS has a good AHRS unit (but no backup AHRS) I wondering whether a Sport unit might be better for the lower EFIS (MFD unit). What are your thoughts?

Finally, from a cost vs aircraft value perspective, do you think a more modern EFIS with synthetic vision will increase my aircraft’s market value equal to the cost of the upgrade?

If all this works out then I might consider upgrading one of my 430s’ for a WAAS Comm/navigator next year.
 
Tankerpilot75 said:
These questions are for those GRT users who have upgraded their old WS system to the newer Horizon EX. Besides a brighter screen, adding synthetic vision and having a faster processor:

1. What other advantages have you seen from the upgrade?

2. Was it difficult to swap out from the WS to the EX from a panel perspective (ie the alignment of the different mounting holes and threading them)?

3. My current gps Comm/navigators are two non-WAAS 430s. They require an ARINC module for EFIS communication which is mounted on the back of the top EFIS. I understand the EX requires a separate ARINC module that doesn’t mount on the EFIS. How difficult was this to wire up and mount? Where did you place the separate module?

Since my panel has two 430s, can I connect both 430s to a new ARINC module and select either one for EFIS use?

4. The old WS does not allow voice warnings to the aircraft intercom and the EX does. What wiring changes did you make to accommodate this capability? I currently have the Garmin 340 system installed.

5. Right now I feed traffic and weather information from my Stratux adsb in receiver to my bottom WS EFIS via hardwire. Traffic does not appear on my top WS EFIS on the PFD display. From the pictures I’ve seen it appears both obstacles and traffic are displayed on the EX PFD page. Does anyone have experience with this?

6. The EX Users Manual says, “ The Horizon EX is intended as a drop-in replacement for the Horizon WS with all the functionality of the WS, plus synthetic vision, a display with four times the resolution, and more. Analog localizer/glideslope inputs are not provided however, although VOR/ILS serial inputs using the SL30 protocol are supported.”

Since I fly ILS approaches does this statement mean that the EX does not support VOR/ILS approaches? This could definitely be a deal killer.

7. The EX Sport (vs the Horizon EX) include’s an internal AHRS unit. While the Horizon EX utilizes an external AHRS. Since my WS has a good AHRS unit (but no backup AHRS) I wondering whether a Sport unit might be better for the lower EFIS (MFD unit). What are your thoughts?

Finally, from a cost vs aircraft value perspective, do you think a more modern EFIS with synthetic vision will increase my aircraft’s market value equal to the cost of the upgrade?

If all this works out then I might consider upgrading one of my 430s’ for a WAAS Comm/navigator next year.
Click to expand...

While I have an HX pair, I can answer a few of the questions.
#3 and #6. general rule: one ARINC "out" a/B pair can drive several ARINC "ins", but an ARINC "in" pair can only see one ARINC "out". You have to see how many ARINC "in" ports are on the adaptor. Each 430 has two ARINC "out" ports, one for GPS, one for VOR/ILS. You need to see how many ARINC "in" ports are offered on the GRT adaptor. If there are 4 ( doubt it) you can wire up both 430's for gps and vor/ils. If there are only two "in" ports on the GRT adaptor, you can run the wire pairs thru double pole, double throw switches, and select gps from #1 or #2 gps, same for VLOC data. If there is only 1 in port on the get adaptor, then you would need to switch all 4 pairs, choosing which one you want. (I haven't seen the adaptor but, judging by the HX, my guess is you have 2 "in" ports). BTW, some gps data is sent over an RS-232 line, so the EFIS units will still get gps position data regardless of these switches. But you need the ARINC lines for approaches.
#4. I ran a single wire, unshielded (if it was a long run I'd use shielded cable) from the HX to an unswitched input on my intercom. You can adjust the volume from the EFIS menu. Works fine.
#5. The newer GRT boxes (my HX, for example) have much higher box-to-box communication speeds, so yes, you can move traffic and wx between boxes. For wx you may need the Ethernet link installed (I think it is standard, it is on the HX).
#7. I do not know how well a sport-to-horizon works. As usual, the Sport will have fewer RS232 ports, so count up, carefully, how many you will want/need. It's surprisingly easy to run short! I will point out that GRT often has package deals where they will throw in a dual remote AHRS box for the price of a single one.
"Finally..." I would say that you never get back the full cost of an upgrade on re-sale. Except, maybe paint. A good paint job seems to make buyers go crazy.
I'll add that you are missing WAAS LPV approaches. Depending on the type of flying you do, this may be a big deal, or not. I would not upgrade the 430 to a 430W, it's already pretty old and the upgrade not cheap. Get the new 175 (??) instead. OR, wait and see what happens with GRT's self-contained gps approach system, which currently is being beta tested (you can get it now), but with no plans for a TSO or other FAA approval. If that works for you you can save quite a bit of money.
 
Thanks Bob

I appreciate the clarifications you gave.

One question: what is the GRT self contained gps approach system you mentioned in beta testing? I asked GRT a question regarding whether they plan to add LPV approach capability to the EX and they said “no”. Is the GRT approach system a stand alone module one would add to their EFIS system like the ARINC module?

My WAAS gps considerations right now are to replace my primary (top) 430 with either the Garmin 355 Comm/navigator or an Avidyne IFD 440. Cost of course is the major consideration.
 
I replaced my PFD H1 WX with a Horizon EX. I did not have ARINC on that box. It is on my second WS. The hookup was plug and play plus a backup and restore to get my settings into the new EX.

I made a drill template that screwed into the old holes in the panel and guided my drill for the new ones.

I don't understand the issues with weather and traffic. I have no problems showing both on both screens. Old or new.

The new screen is brighter by a lot. Pixels smaller and as a result more data is displayed such as ADSB N-numbers....:eek:. Old screen would not. Too coarse pixels. Can run the engine display on the bottom too although I don't do that often since my panel was designed to be functional without it. Again, tighter pixels do allow me to run split PFD and map. I did not do that often with the HS because I thought the PFD display was too cluttered. One whole screen was PFD and the other WS was run split Engine/Map. Now I use the EX with PFD and split map on 20 mile emergency range and the WS as before with engine and 100 mile or so strategic range. SO...yes, the EX has changed how I use the screens.


ILS. Not to worry. GRT is talking about dropping the MANY wire analog connections that were used to connect old school Localizer/GS equipment. I may have been the only customer to use those 10 years ago. Seems like it anyway. Your 430s have ARINC outputs for which you will need an external GRT ARINC convertor to get LOC/VOR/GS. I can't comment past what Bob said about a switch for your 2 430s......unless you have 2 EXs..... there might be a way to make 2 separate ARINCs on 2 EXs play together but I'm not sure how the interdisplay link would be configured.
 
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It may be that the grt approach system was only available on an Hx or HXr, and, as I said was in beta test. Perhaps it was put on the back burner. It used their $500 gps being sold for adsb use, with all the extra software residing in the efis, to generate LPV data. I thought it was a great idea, but the engineering/paperwork cost of getting a TSO are astronomical for a small company.

The HS and, I think, the WS, do not have the bandwidth to send wx data between units. But if your adsb-in device can output data via RS232 and you have the ports available, you can just wire the data from the adsb-in to both WS boxes.

Also as someone mentioned above, if you buy two ARINC modules, you can wire one 430 to one (if there are two inputs available), and the second 430 to the other, then share the data via the ethernet link between efis units. You’ll want to understand the failure modes: if efis #1 dies, then you will lose the arinc data from #1 as well, it won’t transfer if the box dies.
 
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