That must be a later GTX330 firmware. Interesting…
Peter wrote:
and it doesn’t go anywhere
In our previous installation the GNS TAS page did use the GTX330’s OAT data. It also had a pot in the OAT probe circuit for calibration. This is not part of the IM so you need to get it approved separately as a minor change which should not be a problem since this is only advisory data.The later Aspen versions do have an electronic OAT calibration option.
You definitely need heading from the compass system to get a wind vector.
There is also an option on the Garmin transponders to provide an OAT input.
Indeed, but it is very inaccurate (with errors reported up to 6C, and with no calibration procedure) and it doesn’t go anywhere other than the transponder’s LCD. The GTX330 for example has ARINC429 out but it carries only the pressure altitude. It’s always a missed opportunity to have a box with ARINC429 and not have it do a lot more.
Peter wrote:
Actually I wonder just how many GTN/IFD owners do have airdata?
I have airdata and hdg from the Aspen displayed both on the gtn750 and gns430 via a common rs232. The map view shows a wind arrow and speed number. It is possible you need a hdg input to display the wind.
Yes, Peter, you’re right about the ADC200. Here are most (& the relevant ones for this discussion) RS232 input config options for the IFDs:
Peter wrote:
I assume Avidyne aligned the IFD requirements with GNSx30 requirements – for obvious reasons. And since a GNS can accept ADC200 data, the IFD must also otherwise they could not sell it as a plug-compatible replacement.
Yes, they do. So in theory if the GNS can accept ADC200 data then the IFD should too. I’ll dig a bit more on the RS232 part.
I’m planning to replace my old primary AI with a G5 over the winter, mostly to get baro-altitude to the IFD which allows automatic leg sequencing at altitude which is common around here on missed approach procedures…. i.e. climb to xxx feet and then turn to ….
I already have other data such as fuel flow and temp from my JPI, so adding a TAS1000 is a lot of money for little incremental benefit. The G5 is a big step up in presentation and gives some redundancy for the altimeter. I haven’t been able to determine though, if TAS is among the Arinc labels sent by the G5 to the IFD which it needs to display the wind vector.
OK… hmmm. Interesting and very useful.
The ADC200 doesn’t do ARINC429 and probably anything that does is going to be a lot more recent and expensive.
So the Q is whether the ADC200 produces the same RS232 data stream as the TAS1000.
I assume Avidyne aligned the IFD requirements with GNSx30 requirements – for obvious reasons. And since a GNS can accept ADC200 data, the IFD must also otherwise they could not sell it as a plug-compatible replacement.
I will email Shadin…
I don’t have room in the panel for a TAS1000, and such hacking would multiply the installation work. The ADC200 is already constrained in where it can go because the TB20 is fairly full (well, mine is 
) in all the obvious places – except at the bottom of the plane and it ought to not go there because it should not go where water can collect in it. In fact I am certain there is no room for it behind the panel.
From the TAS1000 IM:
So its output must be same as the ADC200’s output – because the two King boxes are prehistoric. And the KLN94 has no config for the type of ADC:
The KLN94 IM contains the full details of the data stream… but the TAS1000 IM doesn’t.
The IFD has this in the IM regarding Air Data sources, so these are the officially supported boxes.
However … it also says the following, which is not device-specific:
