Pop up mode C red circle, analysing after flight, glider sights/sites

[neilmurg]

My PAW is working well as far as I can tell but I have some questions: I fly from Blackbushe, usually around the SE
In flight I get occasional red circle warnings and only see the aircraft less than 1/2 the time. My warnings are set for close approach only, and SD is set +/- 1,000. Does everyone else get this?
If I replay a flight file and watch it on SD, does Mode C/S traffic pop up in the same place I originally saw it at the same time?
I regularly get gliders (:thumbs up:), what proportion use OGN as I'm not flying your 'golden triangle' Wellesbourne/Coventry at the moment?

Is there an easy way to tell which targets are PAWtoPAW contacts?

Any advice / steer to doc appreciated. And thanks, great product

[Keithvinning]

My PAW is working well as far as I can tell but I have some questions: I fly from Blackbushe, usually around the SE
In flight I get occasional red circle warnings and only see the aircraft less than 1/2 the time. My warnings are set for close approach only, and SD is set +/- 1,000. Does everyone else get this?

This is quite possible. With Mode C/S targets being bearing less these may be behind you.

If I replay a flight file and watch it on SD, does Mode C/S traffic pop up in the same place I originally saw it at the same time?

Yes this will be a facsimile of your flight

I regularly get gliders (:thumbs up:), what proportion use OGN as I'm not flying your 'golden triangle' Wellesbourne/Coventry at the moment?

Its just the Golden Triangle at the moment although there are a couple work in progress at Reading and Guildford. The more the merrier. We have ordered the first batch of 25 Factory Built OGN Co-linear antennas from the Far East, so those that want to install them at there locations will soon be able to.

Is there an easy way to tell which targets are PAWtoPAW contacts?

Yes go to the traffic page and it will identify what the type of target is. This is explained in the latest working instructions available at
http://www.pilotaware.com/wp-content/uploads/2017/02/170223-Operating-Instructions.pdf. There is also a You Tube video that explains the traffic page

Any advice / steer to doc appreciated. And thanks, great product

Thanks for your support Neil.

[Ian Melville]

I didn't think bearingless targets were recorded for playback ?

Also on playback you cannot tell what the source was as they all show as FLARM. Live you can as Keith mentioned.

Neil, you don't say what setting you are using in the PAW for bearingless targets, it could be that you have this set too high and the red rings are infact aircraft many miles away. It's not going to work all the time, but there is a happy medium.

[Admin]

I didn't think bearingless targets were recorded for playback ?

If they are not I think that is a bug, they were intended to be recorded & replayed
Thx
Lee

[Paul_Sengupta]

I still receive my own transponder from time to time, especially during climbing or descending.

[exfirepro]

Neil,

What setting do you have configured in PAW for Mode CS? As you have a transponder you must use the Mode CS +Filter (Beta) setting to help prevent the unit detecting your own transponder. The 'Display within vertically' settings in SKyDemon BTW only apply to known bearing targets. Altitude filtering for 'bearingless' Mode C/S targets has to be set in PilotAware.

WRT the red 'Mode C' danger alert circles, what version of PilotAware software are you running Neil? Some earlier versions could falsely display Mode C danger (red ring) alerts from 'own transponder' during rapid climb or descent. This was addressed in more recent revisions (though this phenomenon does still seem to appear in a few cases). It is therefore essential that you always install and run the latest available software (currently Version 20170223).

I'm also a bit confused when you say 'I regularly get gliders', do you mean visually or on SkyDemon?

Outside the OGN-PAW test areas (mainly the 'Wellesbourne Triangle', but potentially also around Coventry, Thame, Guildford and possibly Stoke), you are very unlikely to 'see' gliders on SkyDemon unless you are also running FLARM.

Any clarification will be gratefully received.

Regards

Peter

[neilmurg]

I should have said (though there are clues in the text). I have set in PAW: short range, +/-500 feet, CS + Filter (Beta). Skydemon is set for +/- 2,500 feet and bearingless targets
PilotAware Version(20170223) License Expires(20180518)
I transpond on C+S always. I don't have any FLARM

With the help of this thread, I did finally get to replay a track, Rougham to Blackbushe. Didn't see any bearingless, but I was doing other things. I'm running the Bbushe - Rougham now, just passing north of Farnborough on the way to Biggin Hill (they route me North abeam).

On the above track I saw and had on SD a glider near RAF Cardington. I'm sure I've seen them before around Lasham, maybe they were PAW or ADS-B, how can I tell now?

Hope that helps, ask away. Now I have the tracks on my laptop, how can I analyse them for aircraft observed, ie, which lines to I search for and extract. I'd like to write a macro/program that could give me a summary of which aircraft PAW spotted for me and whether they were, ADS-B, S, C or PAW -** hold on, I'm figuring out the PFLAA messages etc, I'll analyse my track and give a summary **-

Also, I'd like to replay tracks at 2, 5 and 10x speed (pretty please)

[exfirepro]

Hi Neil,

Yes, I did pick up on the short range bit. As I say, these settings only control bearingless (i.e. Mode C/S targets). I just wanted to check your other settings so I can comment definitively.

Gliders around Lasham makes sense as there appears to be an active OGN-PAW uplink installation nearby. The RAF training fleet are also reported to run FLARM, so they will also be rebroadcast by any nearby OGN-PAW uplink installations. I saw loads around Leicester en route to the microlight fair at Popham last month.

WRT your 'rogue' Mode C alerts, either as Keith has suggested they were 'behind you' or you are also experiencing the self reporting phenomenon caused by sudden or rapid change in altitude. Looks like Lee might need to revisit this issue.

Although possible, gliders are unlikely to be running PAW or ADSB, due to the relatively high electrical drain, though some motor gliders certainly do so. There's no easy way to tell ADSB from PAW in flight, other than from the codes on the PAW Traffic Page - unless both of you are set to the same Group ID e.g. 'PAWGRP' in PAW's Group ID field, when the other aircraft callsign will show on your display with # brackets, e.g. #GABCD#......unless the other aircraft is also transmitting ADSB.

I'll let Lee come back re the track analysis/replay issues.

Regards meantime

Peter

[Admin]

Hi Neil

how are you trying to decompose the track files ?
I already have a TCL parser if that would help ?

anyway the format is pretty simple, you have
$GPxxx - NMEA Messages
$PFxxx = Flarm Messages

Additionally you will see
$PAxxx - PAW messages
These are diagnostic, or provide tagged information to better understand the FLARM messages
for example

Code: [Select]

$PAWRT,4B19D1,1,1,1,1,0,0,*4BThis says the ICAO/Code 4B19D1 is transmitting
1,1,1,1,0,0
Mode-A, Mode-C, Mode-S, Mode-S/ES, PilotAware, Flarm

you will also see

Code: [Select]

$PALOG,FF4440,AUDIO,MODEC,,,222*75
$PALOG,4787B2,AUDIO,GPS,9.99,1043,191*13
$PALOG,4AC8B3,AUDIO,MODES,,,162*19
This indicates what messages were passed out to the audio

Hope that helps

[neilmurg]

I thought it might be useful to be able to say:
Flew for an hour today and PAW spotted x Mode C, y Mode S, z PAW targets. Rather too many ADS-Bs for me as I pass Heathrow and/or Gatwick
For mode C/S I had 5 green, 4 yellow, 1 red zone alerts (ie warning circle for bearingless).
For targets it would be nice if it was distinct aircraft rather than number of hits which is OK for Mode S, but not mode C?

Would it be useful if I could identify where on my log I'd had a red circle alert for instance? You may already have this covered. Unfortunately by the time I've finished a flight, I'm a bit hazy on what happened where, and I'm usually solo or with pax that can't help with the analysis.

I've finished replaying the weekend flights. One interesting thing was I was followed by G-BUWK, that was displayed twice, it seems to transmit ICAOhex 40345F instead of 403767

[Ian Melville]

UK, may not have wanted to take avoiding action, it would have messed up his spelling 😜

https://www.flightradar24.com/data/aircraft/g-buwk#d92b078

[Admin]

Hi Neil

For targets it would be nice if it was distinct aircraft rather than number of hits which is OK for Mode S, but not mode C?

I'm afraid dont understand this statement ?
are you referring to the track file format ?

Thx
Lee

[neilmurg]

UK, may not have wanted to take avoiding action, it would have messed up his spelling 😜
https://www.flightradar24.com/data/aircraft/g-buwk#d92b078

lol, that was him? He seems to be using the hex for G-TECC, OR they were flying as a pair to Rougham?

[neilmurg]

For targets it would be nice if it was distinct aircraft rather than number of hits which is OK for Mode S, but not mode C?

I'm afraid dont understand this statement ?

Thx
Lee

I analysed the track data to look at what warnings I got in a 1 hour flight (which is what I was after), I got this:

1  $PALOG,4B1870,AUDIO,GPS,6.95,1475,78*23
   $PFLAA,1,-6685,2043,478,1,4B1870!HBJGQ,239,,83,16.8,8*7D
2  $PALOG,401082,AUDIO,MODES,,,182*67
   $PFLAA,2,3000,,-100,1,401082!G-VVBL,,,,0.0,8*36
   7 more hits
3  $PALOG,FF0260,AUDIO,MODEC,,,255*75
   1 more hit
4  $PALOG,49125A,AUDIO,MODES,,,209*12
   $PFLAA,3,1500,,151,1,49125A!NJE418R,,,,-7.6,8*0A
5  $PALOG,405C61,AUDIO,MODES,,,177*17
   $PFLAA,1,4500,,-88,1,405C61!G-PTEA,,,,-6.1,8*58
   5 more hits
6  $PALOG,401A19,AUDIO,MODES,,,181*17
   $PFLAA,1,4500,,-78,1,401A19!GBANX,,,,0.0,8*4C
   1 more hit
7  $PALOG,4844B2,AUDIO,GPS,5.38,-1719,197*37
   $PFLAA,1,-5508,1070,-483,1,4844B2!P4NGK,207,,78,41.1,8*24
8  $PALOG,49130B,AUDIO,MODES,,,175*1D
   $PFLAA,1,4500,,133,1,49130B!NJE3ZP,,,,0.0,8*74
   2 more hits
9  $PALOG,40345F,AUDIO,GPS,10.00,-398,55*07
   $PFLAA,0,-7751,7485,-98,1,403767!G-BUWK,359,,35,0.0,8*12
   10 more hits
10 $PALOG,FF0560,AUDIO,MODEC,,,255*72
   $PFLAA,3,1500,,-56,1,FF0560!Mode-C,,,,0.0,8*27
11 $PALOG,400FC3,AUDIO,MODES,,,197*6E
   $PFLAA,2,3000,,152,1,400FC3!G-JVBP,,,,-3.0,8*3F
   5 more hits
12 $PALOG,407260,AUDIO,MODES,,,213*64
   $PFLAA,3,1500,,100,1,407260!GCJTE,,,,0.0,8*2E
13 $PALOG,FF0330,AUDIO,MODEC,,,237*75
   $PFLAA,3,1500,,-40,1,FF0330!Mode-C,,,,0.0,8*23
14 $PALOG,406162,AUDIO,MODES,,,174*66
   $PFLAA,1,4500,,-55,1,406162!GCGDC,,,,0.0,8*2E
   11 more hits
15 $PALOG,FF0610,AUDIO,MODEC,,,235*70
   $PFLAA,3,1500,,49,1,FF0610!Mode-C,,,,0.0,8*00

15 Warnings, (4-C, 8-S, 3-GPS)

[Admin]

Hi Neil
you do realise that mode C does not provide an ICAO code which is why it cannot be displayed ?
Mode C is just a  special squawk code to indicate altitude

Thx
Lee