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Any AP track GS/LOC?

bkthomps

Well Known Member
Do any of these AP's available for experimentals track GS/LOC?

I looked briefly at the major brands but didn't see any mention of it, am I blind?
 
Unless I don't understand your question,

No.

Those that have vertical coupling like the TrueTrak VSGV model will follow vertical as well as horizontal guidance from compatible nav/GPS equipment like a Garmin 430W.

They don't know where they are by themselves.
 
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Do any of these AP's available for experimentals track GS/LOC?

I looked briefly at the major brands but didn't see any mention of it, am I blind?

Yes......if you have the proper nav equipment.

Check with TruTrak and Trio Avionics for details.
 
Pretty sure Trio does not offer NAV support of any kind.

TT has some models that will but they are the high end models.

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Several models can track GPSS & GPSV (ARINC429 GPS Steering) commands.

Problem is that most if not all NAV radio's do not output the NAV data on ARINC 429 as GPSS & GPSV signals....they either output analog NAV data or output the NAV data on other 429 labels that the AP's can't (or won't on purpose) read. They charge extra for the NAV interface/programming!

BUT...Some EFIS systems have the ability to take the analog Nav data or the 429 Nav signals and transfigure that data and output the GPSS & GPSV signals needed by the lower end AP's...pseudo VOR/LOC/GS tracking...

I think GRT, AFS, and MGL all three have these pseudo modes. Dynon does things a little different. They do have GPSS and ARINC support of GPS & NAV radio's but only on the roll axis. For some Nav radios, they also have an analog interface (very limited # of radios supported). They do not support verical steering of any type yet.

Dynon leaves the driving of the AP inside the data source. They just follow the needle....
 
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Our Sorcerer will couple to a glideslope and track a localizer. Also, our EFIS AP IV will do it when connected to an SL30, or 430 with our TS-43 Arinc module.
 
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Yes......if you have the proper nav equipment.

Check with TruTrak and Trio Avionics for details.

I believe the Trio Pro Pilot will couple to the Garmin 430/530 and SL30 via the ARINC interface built into the autopilot. But give Jerry at Trio a call to get details.
 
The SL30 does not have any ARINC interface....It's either serial (RS232) or Analog...(the AP/EFIS must speak the SL30 protocol or connect to the analog interface)

The 430/530 have both GPS Arinc and VOR/ILS Arinc interfaces and they are two different creatures. Support for one does not automatically give you support for the other....The software in the AP/EFIS must understand the different labels and have two ARINC inputs or have the ability to detect what is being fed to it.

Our Sorcerer will couple to a glideslope and track a localizer. Also, out EFIS AP IV will do it when connected to an SL30, or 430 with our TS-43 Arinc module.

I believe the Trio Pro Pilot will couple to the Garmin 430/530 and SL30 via the ARINC interface built into the autopilot. But give Jerry at Trio a call to get details.
 
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The TT Sorceror will absolutely couple to either ground based nav (VOR/LOC/GS) however the lower model TT and other experimental APs will generally not. However with that said, several of the experimental EFIS models will do a translation internally taking in VOR/LOC/GS and convert to GPS lateral and vertical steering commands. This is how the GRT, AFS and Cheltons work. I can't speak directly for the TT EFIS but suspect that's what it does as well. This is why you see the TT Digiflight II-VSGV being so popular among homebuilts.

An interesting note here is that the Garmin G900 does NOT do this conversion/translation since it's largely based on the certified hardware/software.

Bob
RV-10 N442PM
 
if i'm flying IFR i really don't want anything translating anymore than it has to

it sounds like the resounding answer to this question is yes, but you'll pay for it

in the interest of staying alive and flying safe that is
 
I believe the Trio Pro Pilot will couple to the Garmin 430/530 and SL30 via the ARINC interface built into the autopilot. But give Jerry at Trio a call to get details.

If it does that, then it also ought to couple to the GNS-480 (Apollo CNX-80). Those units have the ability to output SL30 mode ARINC.
 
Do any of these AP's available for experimentals track GS/LOC?

I looked briefly at the major brands but didn't see any mention of it, am I blind?

Just as an FYI, ILS is receding and GPS is growing, with GPS precision approaches now available more places than ILS and usually available anywhere having an ILS.

If you just have to fly the ILS, with most of the autopilots you can dial in a ground track in degrees (making adjustments as needed) and dial in a descent rate. 400-600fpm will usually nail the ILS depending on your airplane and winds. With a good EFIS, just fly the GPS to intercept the ILS then "steer" using the course and vertical speed selects - it's a piece of cake and works no matter what the winds.
 
For the MGL systems the answer is: "It depends on how you use the system".

If you are using an external autopilot via NMEA:
GPS navigation only (i.e. "goto" or "route/flightplan" horizontal navigation using internal GPS).
VNAV NMEA message can be enabled but I am not aware of any AP actually using this.

If you are using an external autopilot via ARINC:
The AP can follow the HSI and GSI as selected on the EFIS. The AP of course needs to have support for VNAV or else you only have horizontal navigation.

If you are using the internal autopilot (i.e: controls servos directly from the EFIS):
Very similar to the ARINC AP - the AP follows the HSI and GSI indicators.

This means for all solutions, except the more primitive NMEA control, you can have the AP stear whatever is selected on the HSI and/or GSI.
The selection depends on what you have installed plus the internal sources.

Typical external sources: G430W, SL30, analog nav radios (+/-150mV outputs). This means GPS nav, VOR. ILS etc.

Typical internal sources: Internal GPS NAV (goto, flightplan), simulated ILS and GS using GPS (we call it GLS) , simulated VOR (we call it GVOR) as well as heading and altitude bugs.

Pretty much covers everything...

*) Enigma does not have ARINC or analog nav inputs so can only do NMEA and internal autopilot with internal sources and SL30. Voyager and Odyssey can do everything.

Rainier
CEO MGL Avionics
 
Just to be clear, the only experimental standalone A/P I'm aware of right now that'll directly fly raw analog NAV/LOC/ILS/GS/VOR signals is the TruTrak Sorcerer and AP-100 (and some older models). Along with the Analog hooks, it has ARINC and RS-232, and additionally will take heading bug pick-offs from some DG's and EFISes...although the only EFISes I'm aware of that are outputting the direct +/- heading bug info are Garmin. Some of the S-Tec and other certified stuff will also talk to raw NAV signals, but they are mucho $$'s.

As others said, when you get an EFIS involved it depends on a number of factors including the equipment driving it and what it supplies for signals (and how the EFIS translates said signals), and many times it can be a yes & no type answer...and while some of the EFISes do a fantastic job of handling the A/P, others have had less than stellar success. There are a lot of variables, but when it comes down to it, the simple answer to your question is above. The Sorcerer may seem pricey until you compare it to anything certified!

Cheers,
Stein
 
Just as an FYI, ILS is receding and GPS is growing, with GPS precision approaches now available more places than ILS and usually available anywhere having an ILS.

If you just have to fly the ILS, with most of the autopilots you can dial in a ground track in degrees (making adjustments as needed) and dial in a descent rate. 400-600fpm will usually nail the ILS depending on your airplane and winds. With a good EFIS, just fly the GPS to intercept the ILS then "steer" using the course and vertical speed selects - it's a piece of cake and works no matter what the winds.

are you aware that currently, today, there is only ONE functioning WAAS satellite?

http://www.aopa.org/flightplanning/articles/2010/100413waas.html

I like redundancy with my redundancy, was that redundant?
 
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