Mode-CS (Beta)

[Paul_Sengupta]

I went flying today with the latest software and I didn't get a single spurious (own) warning. Has the algorithm been updated?

[Admin]

I went flying today with the latest software and I didn't get a single spurious (own) warning. Has the algorithm been updated?

Yes it has !
Specifically enhancing the filtering

Would h interested in the software versions where users are seeing false positives

[rogerabc]

I was running PilotAware Version(20161124) today & the suspect false warnings were bad enough to make me switch off.

Roger

[Admin]

I was running PilotAware Version(20161124) today & the suspect false warnings were bad enough to make me switch off.

Roger

Hi Roger
Can you please send me
1. Screenshot of config page
2. Track file from flight

I will investigate
Thx
Lee

[rogerabc]

Many thanks,

Sent by direct email due to 512KB attachment restriction.

Just before t/o a hercules flew close by at low level & we had a perfect mode c traffic alert/wng, then about 15 mins into the flight the ghost warnings began, no traffic seen despite repeated turning & scanning, then I turned the PAW off.

Best regards,

Roger

[EricC]

Hi all.

The screen shot may be of interest.
Mode C  seems to show the same return multiple times.

[exfirepro]

Hi Eric,

That's normal. Think of the  traffic screen as a sort of 'collection box'. The Mode C entries are all held here while the system analyses and compares them to establish whether they are threat aircraft or 'duplicate' altitude responses from mode  S/ADSB aircraft already in the table, before deciding what to do with them. The T= bit denotes the time each mode C response has been in the system. They are only passed to the Nav System for display (with associated audio alert) if they are deemed to be a genuine mode C target and if this becomes the principle bearingless target at that point in time.

Roger,

I'm surprised you are getting false alerts. Mode C has proved pretty reliable with the exception mentioned by Paul above where rapid climb or descend could fool the system into seeing your own transponder as a threat, but Lee modified the software to deal with this and as Paul has reported, this problem seems to be now resolved. Your configure setup and log will give Lee the data to see what is going on.

Do please bear in mind that PilotAware 'Mode C' was released as a beta due to the number of users pressing for an early release. Although we are generally happy with it, it is still subject to ongoing testing and (where necessary), tweaking.

Regards

Peter

[Paul_Sengupta]

I got a lot of alerts yesterday but that was because there was a lot of traffic around. 

All the bearingless traffic I saw was Mode S though, giving a callsign. Don't think I saw any Mode C at all, though I concentrated more on the altitude than the registration.

[EricC]

Thanks for the info.....now understand
the T  bit..

Thanks EricC

[Admin]

Sharing Rogers experience ....

There were no Mode-C Audio messages in the track file supplied, there were 2 sequences of Mode-S,
The two aircraft were :-

43C1AB, I saw it here (Apparently a hercules transport which you mentioned)
$PFLAA,1,4500,,125,1,43C1AB!RRR298,,,,1.3,8*63
$PFLAA,2,3000,,125,1,43C1AB!RRR298,,,,0.0,8*60
This is saying it was within 125ft of you vertically - that's pretty close!

400FB6 (G-JKMH)
$PFLAA,3,1500,,200,1,400FB6!GJKMH,,,,1.5,8*34
This is saying it was within 200ft of you vertically

There were a total of approx 30 Audio messages, this issue was that the signal was coming and going causing the
threat to appear to reduce, then increase.

Definitely not a Ghost

Maybe you know G-JKMH ?

Thx
Lee

[rogerabc]

Well I certainly stand corrected on this one.

Having checked the registration on FR24, we were in the same part of the sky at the same time yesterday & a big lesson learned.

Thanks everyone for their comments & apologies for my criticism of the product.

Best regards,

Roger

[Admin]

Having checked the registration on FR24, we were in the same part of the sky at the same time yesterday & a big lesson learned.

We are all still learning Roger 

[exfirepro]

Hi Roger,

Good to get positive feedback from Lee and to know the system was doing what it is supposed to. I'm not sure what 'Mode C/S Detection Range' setting you are using, but I take it you know this is in effect a 'sensitivity control'. If you get too many 'Bearingless' target messages ( - i.e. the Traffic Notice / Traffic Alert / Traffic Danger variety), it might be worth trying a shorter range setting, which will decrease the warning distance but significantly reduce the number of alerts. ''Short' or 'Medium' Range settings generally work well unless you operate very close to a large airport or very busy airfield,when you may want to try Ultra-Short Range, but tread carefully!!

Any problems get back in touch.

Regards

Peter

[grahambaker]

I am continuing to get spurious returns, I believe, on the latest version.

I am using the '+Filter' option, and have '+-2000'' and 'Short Range' set. Descending from FL100 over mid-Wales today I was getting an intermittent warning of Mode C traffic either 100' or 200' below me most of the way down.

Unfortunately I didn't save the settings page nor track logs.

[exfirepro]

Hi Graham,

You say you are running the latest software version, which includes a fix for an issue where own transponder could register as a threat during rapid climb or descent? This sounds very like the problem you were experiencing, but should now be fixed.

Lee has been away, but back this coming week. If you have your track file, I'm sure he would be keen to take a look at it.

Regards

Peter