Display Question

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JimB
Posts: 87
Joined: Tue Mar 12, 2013 12:52 am

Display Question

Post by JimB »

I have two Sport HS displays and a GNS 430.

The pfd display shows course deviation beneath the attitude indicator. It is labelled GPS. When I switch my GNS430 to VLOC mode (press the CDI key) the pfd deviation still is labelled GPS. Is it possible for it to display VLOC deviation? GNS430 is connected by ARINC, both GPS and VLOC and a serial link.

When flying an approach, the MFD display "shows" the approach. But sometimes it doesn't show the course reversal. I'm not really sure when it does or doesn't but shouldn't it always include the course reversal?

Thanks

Jim Butcher
Bobturner
Posts: 444
Joined: Mon Mar 11, 2013 6:34 pm

Re: Display Question

Post by Bobturner »

Yes, it should show VLOC data. Some where in the setup menu there is a question that goes something like this,’switch efis mode when 430 is switched from gps to vloc’, or maybe it’s the other way around (I have a 420 so don’t have this problem). Make sure you have the correct setting. Alternatively, you can switch both the 430 and the HS.
The course reversal data is not in the HS, it resides in the 430. So I *think* that to display it you need to be in GNAV mode. Jeff can confirm.
GRT_Jeff
Posts: 802
Joined: Tue Dec 11, 2012 12:11 am

Re: Display Question

Post by GRT_Jeff »

If none of the indicators change, then it could be SET MENU, General Setup, NAV Mode Source. That should be External to follow the 430 mode.

The 430 flight plan data doesn't include procedure details like holding patterns or procedure turns. It only sends the waypoints. GNAV mode can use the lateral commands from the 430 to follow these turns but not display them. The flight director and ARINC-429 autopilot output will follow the turns in GNAV mode.
JimB
Posts: 87
Joined: Tue Mar 12, 2013 12:52 am

Re: Display Question

Post by JimB »

Hi Jeff & Bob,

I do not have an autopilot, GRT or other so A/P Mode doesn't mean much to me. But Nav Mode should change from Green (GPS) to White (VLOC) when I select the CDI button on the 430, correct? Does the 430 have to be receiving a VLOC signal to switch mode, ie if no signal does it stay in GPS until it receives the VLOC? I should not have to change NAV on either screen, it should stay in 430, correct?

Since I have ARINC installed, shouldn't the procedure turn and holding patterns show on the MFD screen?

The manuals say the CDI on the PFD is a GPS CDI. Does that mean it doesn't switch to VLOC CDI when the nav source is VLOC? I'm trying to use the PFD and MFD without change when doing an approach (Bob, I find that easier since I am accustomed to where everything is located and how it all reacts - changing to a different display adds complexity to an approach). I need to have a CDI to be legal. The GPS CDI on the PFD is fine for GPS approaches but not so for VLOC approaches.

Thanks for the help.

Jim Butcher
GRT_Jeff
Posts: 802
Joined: Tue Dec 11, 2012 12:11 am

Re: Display Question

Post by GRT_Jeff »

The CDI button should cause the EFIS to switch between a "GPS" indication and a "VOR" or "LOC" indication on the screen. The "NAV MODE" button will not change from "430" because both modes are part of the 430.

The 430 doesn't send procedure turn and holding pattern information so they will not show up. (Some do support sending "GAMA 429 Graphics" but our EFIS still doesn't support that.)

The CDI at the bottom of the PFD, the one that isn't yellow, is always a GPS CDI from the flight plan. You need the yellow indicators toward the center of the PFD to display GPS or ILS approach signals. The lower left edge of the yellow indicators will show the letters GPS, VOR, or ILS, also in yellow. The yellow indicators are enabled by the ILS Type setting in SET MENU, Primary Flight Display. The "Show VOR CDI on Localizer" and "Show GPS CDI on Loc/GS" settings allow the VOR and GPS to show up on the same yellow indicators. "Show GPS CDI on Loc/GS" is required for showing GPS approach deviations.
Bobturner
Posts: 444
Joined: Mon Mar 11, 2013 6:34 pm

Re: Display Question

Post by Bobturner »

Not sure about the Sport HS but the Horizon HS or Hx will show a flight director (FD). Access from the autopilot control page, even if there are no servos. All the guys taking the ATP test ‘cheat’ and use a FD to keep the needles exactly centered.
330drvr
Posts: 69
Joined: Sun Mar 24, 2013 5:30 pm

Re: Display Question

Post by 330drvr »

Bob Turner is dead right. I always use the FD when IFR in all phases of flight whether the A/P is in use or not. The FD "displays" what the guidance is being given to the A/P whether installed or not. This is how an airliner is flown all the time.
RV-7A
Dual HX, Mini X, dual adaptive AHRS, GRT EIS
JimB
Posts: 87
Joined: Tue Mar 12, 2013 12:52 am

Re: Display Question

Post by JimB »

Thanks Jeff. I'll turn on Show VOR CDI and see how that works. I'm glad to know that the CDI under the attitude indicator is always GPS.

Bob & 330drvr, I'm sure the FD is cool, but it requires the purchase of vertical steering for a Sport from GRT. For as seldom as I do approaches, it's not worth it. Actually using the GPS CDI works fine even for VOR approaches but I think it's not really legal.

Thanks for the help and suggestions.

Jim Butcher
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