Using PAW as a source for ADS-B ES out

[tnowak]

A general question:
Does PAW send continuously updated position data to the connected transponder for ADS-B ES out?

A friend with this setup is seeing some strange data on FR24, especially airspeed (in FR24) which is all over the place.

If a Mode S ES transponder isn't interrogated by ground radar how often should it send ES data all by itself?
Every 16 seconds or thereabouts?
Tony

[Admin]

Hi Tony

A general question:
Does PAW send continuously updated position data to the connected transponder for ADS-B ES out?

GPS messages are sent every second.

A friend with this setup is seeing some strange data on FR24, especially airspeed (in FR24) which is all over the place.

Very strange.

If a Mode S ES transponder isn't interrogated by ground radar how often should it send ES data all by itself?
Every 16 seconds or thereabouts?
Tony

This will be dependant upon the transponder itself, but I think it is supposed to send an ES message twice a second.
Now, bear in mind an ES transmission is actually a group of possibilities, and not a case of
/Squawk/IDENT/Lat/Long/Alt/Speed in each transmission, each of the bits of imformation are spread over a number of data packets.

Thx
Lee

[tnowak]

Hi Lee,

Thanks. I think the issue is with his Funke TRT800 transponder needing a firmware upgrade.
Will report back when his issue is resolved.

Tony

[PaulSS]

Hi Tony,

It's probably worth doing a search of this Forum for the TRT800. I'm sure I remember various problems being experienced with that transponder but I can't remember the outcome or whether there was a solution.

I would do the search myself but have to go and do battle with typhoon number 23 and hope it doesn't get too close to Okinawa tonight 

Cheers,

PaulSS

[exfirepro]

Hi Paul,

Tony has had dealings with the infamous Funke ‘requirement to update before you can add ‘ES’’ before, so knows the ins and outs, though this looks like it might be partly an FR24 rather than simply a Funke issue. Yes, please keep us updated Tony.

Hope you have a safe flight tonight Paul!

Best Regards Both

Peter

[PaulSS]

Might have known I was trying to teach egg-sucking 

It was an interesting evening/morning but I think tomorrow will be a bit more of a challenge, with the typhoon moving north over Japan. This was this morning's TAF for our jaunt through Okinawa (Rwy 36). It was bad enough landing but then had to take off again and go to Hong Kong. Glad to say its very pleasant here 

Just thought I'd edit this and add a shot of the ACARS report of the weather we grabbed as we went past Okinawa on the way back from Hong Kong today. Probably not ideal as an alternate 

[exfirepro]

^^^^^^^

Not really sure a ‘like’ was what I meant -  ‘impressed’ would be more appropriate, though perhaps not in my flexwing. I like a challenge and have flown in some pretty ‘interesting’ winds, but it gets a bit hard to ground handle at 40kts - never mind 70 

Respect

Peter

[AlanG]

@Exfirepro

Ahem.  What was that comment the other day about "3 axis bottle merchants" when I mentioned the go-arounds and diversions I'd seen at EGPH on 360Radar

[exfirepro]

That was just a wind-up (or possibly a 'Wind' up)  You well know my 'limits' - or then again, maybe we haven't reached them yet 
 
Regards

Peter

[tnowak]

Well, my friend has had his Funke back and it had a firmware upgrade.
Unfortunately it has made no difference to what is seen on FR24. His cruise speed varies signifcantly from 40 Kt or less to 250 Kt or more.
He doesn't fly like that!

I can only think of two reasons why this may happen:
1. The ADS-B Out position data is in error somehow although the FR24 track looks reasonable.
2. The position data is somehow being stored/delayed occasionally by the transponder before transmissions. So the calculated speed between data transmisisons (position) varies.

Any ideas where to look to fix this issue?
Oh, it is a PAW Classic.
Tony

[Admin]

Hi Tony

Are we sure that the trace that is being shown on FR24 is from ADS-B and not MLAT ?

Do you know which NMEA messages the FUNKE is using to determine the ground speed ?
it is easy to take a look at the .trk file and see if there is anything strange in there

Thx
Lee

[tnowak]

Hi Lee,

The trace is ADS-B as he was flying at 2000 ft in an area of good FR24 coverage (southern England).
Is there a way to check for ADS-B data when viewing playback tracks on FR24?

Are you saying that the Mode S ADS-B data transmitted via a transponder includes ground speed messages?
I thought FR24 calculated that based on the time taken to travel between Lat/Lon corordinate pairs.

Thanks

Tony

[Admin]

Hi Tony,

Hi Lee,

The trace is ADS-B as he was flying at 2000 ft in an area of good FR24 coverage (southern England).
Is there a way to check for ADS-B data when viewing playback tracks on FR24?

I am not sure TBH, but FR24 will capture MLAT(Mode-S) and ADS-B, so the first thing to determine.
is whether the data on FR24 based upon the Mode-S transmissions (via MLAT) or ADS-B transmissions

Are you saying that the Mode S ADS-B data transmitted via a transponder includes ground speed messages?
I thought FR24 calculated that based on the time taken to travel between Lat/Lon corordinate pairs.

No Ground speed is transmitted as part of the Extended Squitter.
The question is, what NMEA message is the transponder using to create that groundspeed component, then we can cross reference that in the .trk file
IIRC, it is one of the following
- GPVTG
- GPRMC

Thx
Lee

[tnowak]

Hi Lee,

Let me get back to you about this issue.
It has it has just been discovered that Funke never upgraded the hardware, just the firmware, although they were asked to do both.....
Hardware is still at the "non ADS-B" level.

Thanks

Tony

[Admin]

It has it has just been discovered that Funke never upgraded the hardware, just the firmware, although they were asked to do both.....
Hardware is still at the "non ADS-B" level.

Hi Tony,
In which case, I am guessing the FR24 trace you were looking at was most likely MLAT and not ADS-B
Thx
Lee