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  #11  
Old 02-14-2018, 08:01 AM
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g3xpert g3xpert is offline
 
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Quote:
Originally Posted by jakej View Post
Steve, Is the G5 nmea output suitable for all the common autopilots ?
Hello Jake,

The G5 RS-232 output may be configured for NMEA at either 4800 or 9600 baud to provide basic GPS data to external devices, but most of us would want a navigator like the Aera 660 to provide NMEA data to an autopilot.

The NMEA data from a navigator like the Aera 660 allows an autopilot like the G5 to couple to a direct-to or flight plan, and even follow vertical navigation (VNAV) from the Aera 660 to descend from cruise altitude and automatically reach pattern altitude at the destination airport at a user specified (configured) distance out from the airport.

In the image above, the Aera 660 is playing the role of the navigator (providing lateral and vertical guidance using NMEA data) for the G5 autopilot.

Just to be clear, if you want to see the autopilot modes and flight director on the G5 display, you need to be using the G5 as your autopilot.

Thanks,
Steve
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Last edited by g3xpert : 02-14-2018 at 08:38 AM.
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  #12  
Old 02-14-2018, 12:13 PM
AndyWW AndyWW is offline
 
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Thanks very much Steve. From your post can I infer that I could get a G5 to drive some GSA28 servos directly without needing a GMC307? That might be another possibility for us.

I think I may have failed to be clear enough on my other question. I was asking how many times per second the G5 outputs the GPS position. The Trutrak autopilot documentation (but I guess it's true for all autopilots) said that to get the best performance the refresh rate needs to be better than once per second.
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  #13  
Old 02-15-2018, 08:20 AM
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g3xpert g3xpert is offline
 
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Quote:
Originally Posted by AndyWW View Post
Thanks very much Steve. From your post can I infer that I could get a G5 to drive some GSA28 servos directly without needing a GMC307? That might be another possibility for us.

I think I may have failed to be clear enough on my other question. I was asking how many times per second the G5 outputs the GPS position. The Trutrak autopilot documentation (but I guess it's true for all autopilots) said that to get the best performance the refresh rate needs to be better than once per second.
Hello Andy,

You are welcome.

While the G5 and GSA 28 servos are the main part of this autopilot, there is no user interface on the G5 for moding the autopilot (for good reason!), so you do need the buttons/knobs/wheel provided by the GMC 307/507 to have an operational autopilot.



The G5 internal WAAS GPS updates at several Hz and the NMEA output is updated at 1 Hz, but again, it is somewhat irrelevant what the update rate of the G5 NMEA output is since you would want to drive an external autopilot with a navigator, not the G5.

Besides, an autopilot should not be dependent on the update rate of the navigator (within reason) to fly the plane smoothly. The GPS TRK, XTK, and speed provided by the navigator are only parts of the flight director solution which incorporates high speed attitude and air sensor data to constantly derive the gain filtered pitch/roll rate used to fly the required heading, track, course, altitude, climb, pitch, roll, etc.

High end IFR navigators like the GNS/GTN provide roll angle steering data over A429 which gives the autopilot more to work with, but VFR navigators providing NMEA data over RS-232 do not provide roll steering data, but this is no problem for the G5 autopilot.

The Aera 660 also outputs NMEA data at 1Hz, which is plenty fast enough for the G5 autopilot to smoothly fly the plane and track a flight plan both laterally and vertically.

Thanks,
Steve
__________________
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Please email us for support instead of using Private Messaging due to the limitations of the latter.

Last edited by g3xpert : 02-15-2018 at 08:35 AM.
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  #14  
Old 06-12-2018, 08:49 PM
andymeyer andymeyer is offline
 
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Steve,

If the 307 or 507 is coupled to a GNS430W or other VNAV capable GPS navigator, will it fly the vertical portion of an LPV approach to minimums like the Trio and others? Will the G5 display flight director cues when appropriately coupled?

Does it have airspeed protections (minimum airspeed during climbs, maximum during descents)?

Will it fly a fixed airspeed (KIAS) climb or descent?

I am considering making this upgrade, but can't find sufficient information on the capabilities afforded by each potential configuration.

Regards,

Andy
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  #15  
Old 06-13-2018, 07:07 AM
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g3xpert g3xpert is offline
 
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Quote:
Originally Posted by andymeyer View Post
Steve,

If the 307 or 507 is coupled to a GNS430W or other VNAV capable GPS navigator, will it fly the vertical portion of an LPV approach to minimums like the Trio and others? Will the G5 display flight director cues when appropriately coupled?
Yes, a G5 based autopilot with GMC 507 autopilot control panel and a GAD 29 A429 interface connected with an appropriate GNS/GTN navigator (like the 430W) can fly both ILS and LPV approaches to minimums.

All G5 based autopilot systems include a flight director that can be used both with the autopilot engaged, and when hand flying the aircraft. This example shows a dual G5 system, but if you have an analog CDI connected to your GNS 430W you may use that instead of the second G5. The GMU 11 magnetometer is optional if you want to use HDG mode. You still have TRK (GPS track) mode even without a magnetometer.



Quote:
Does it have airspeed protections (minimum airspeed during climbs, maximum during descents)?
Yes, you program in the minimum/maximum airspeed limits for your aircraft, and the autpilot will raise/lower the nose as needed to protect those airspeed limits.

Quote:
Will it fly a fixed airspeed (KIAS) climb or descent?
Yes, as shown above, the GMC 507 has an IAS button which may be used to perform constant airspeed climbs/descents.

Quote:
I am considering making this upgrade, but can't find sufficient information on the capabilities afforded by each potential configuration.

Regards,

Andy
Let us know if you need anything else. Here is a link to our price sheet if you need this information.

Thanks,
Steve
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Please email us for support instead of using Private Messaging due to the limitations of the latter.
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