I think what it’s really doing is GPS steering only, the rest is advertising bull**it.
In the same way do I have it with the GTN650. Although the GTN receives and displays the localiser and glideslope and outputs all to the Aspen, it only outputs GPS steering commands. So you have to load the approach if you want to have George to follow it. It’s fine as long as you know what it’s doing.
Garmin never said what and why, but it probably uses GPS data to improve the LOC and GS control loops.
But that begs the Q: why does the GFC600 and GFC700 not need GPS to fly an ILS?
Although the GTN receives and displays the localiser and glideslope and outputs all to the Aspen, it only outputs GPS steering commands.
A GTN contains a VHF/UHF radio which received the LOC and GS signals and outputs analog deviations – same as a normal radio e.g. a KX165. It also outputs both of these as ARINC429 commands, for modern autopilots. There are various subtleties around this. The lateral label is probably the standard roll steering label 121; I don’t know which one is used for the GS. Maybe @wigglyamp knows; not sure he is still around.
UdoR wrote:
Although the GTN receives and displays the localiser and glideslope and outputs all to the Aspen, it only outputs GPS steering commands. So you have to load the approach if you want to have George to follow it. It’s fine as long as you know what it’s doing.
What do you mean with only output GPS steering commands? Do you mean over ARINC? The GTN can certainly output analogue localiser and glideslope deviations.
Airborne_Again wrote:
What do you mean with only output GPS steering commands? Do you mean over ARINC? The GTN can certainly output analogue localiser and glideslope deviations.
Interesting. I’ll have to dig a bit deeper in the setup of my panel, because in my case it doesn’t, or at least if it is output, it isn’t picked up.
Peter wrote:
I don’t know which one is used for the GS. Maybe @wigglyamp knows; not sure he is still around.
173 Localizer Deviation
174 Glideslope Deviation
The GFC500 has just got an SB disabling the eletric trim.
How did they implement that??
The fix is a firmware update, apparently.
The GFC500 has just got an SB disabling the eletric trim.
Why? Can you share the source?
It is from the US Socata owner group. No more detail was provided other than this was a new installation and the trim was disabled apparently “out of the box”.
There was a one-off problem involving auto-pilot commanded runaway trim. Evidently this revealed a bug in the software which could make it happen again.
The fixed software is now available.
I know this because a friend of mine got one installed about a week before the SB came out! But he now has a functioning AP again.
auto-pilot commanded runaway trim
Just what you want in IMC.