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-   -   ADS-B “IN” at Ballina? (https://www.pprune.org/pacific-general-aviation-questions/645962-ads-b-ballina.html)

Squawk7700 7th Apr 2022 11:06


Originally Posted by mikewil (Post 11211890)
in relation to your comment about there being no controls in place about latency etc or the reliability of the 4G network, but really the limited traffic displayed on the device from other devices running the same app suffers similar limitations.

I agree that it is not a perfect solution and shouldn't be relied upon for separation but regarding your comment about an aircraft not being where the pilot expects it to be, isn't this the same problem with TCAS and all the other cheaper GA installations that try and display Mode C/S transponder returns on a map?

The difference in displaying traffic to the same app users versus cross EFB’s is again, if it’s run by the one provider, they can set their own thresholds for display. Eg if the aircraft doesn’t ping for 5 seconds, delete it from the screen immediately. If you’re getting a feed from elsewhere, how do you know what algorithm is in place to provide you with that traffic in the first place? How old is said traffic?

Anything hardware based with a direct live signal reception is y far superior in every way.

TCAS feeds coming from a hardware mounted receiver as going to be as close to real-time as you’ll ever get.

43Inches 7th Apr 2022 12:14

TCAS is designed to highlight conflicts, alert the crew and display a position to assist the crew in visual acquisition of the target. The closer you get to a conflict the more accurate the picture becomes, at range its not highly accurate though. However should you fail to sight the target and it gets too close, the unit will give a resolution to avoid. That's when it starts making lots of noise, things turn red etc... It is not designed to be a quasi radar scope, you can't say for sure a target is X aircraft as it does not display enough information. However that said, you can see stuff at range and then get an idea something is out there and try to communicate with it, so for situational awareness it is pretty good. I'd still separate by a safe margin altitude, track, distance, but you can use TCAS to see when something passes, then talk to it to get actual position to confirm clear. That then relieves constant position updating and radio clutter. eg " XXX I'll maintain 6000, you stay at 5000" then watch it pass on TCAS, "XXX whats your current Distance and track", (XXX responds with a GPS distance and track away from you), "XXX all clear, see ya later" or whatever.... Good thing is if either party stuffs up the TCAS will show it happening and you can query them and get ready for avoiding action.

KRviator 7th Apr 2022 21:21

The other problem with OzRunways and AvPlan traffic is, unless it's from an ADS-B output (and even then there's a lot of erroneous callsigns, particularly among the RAAus/HGFA crowd), the callsigns often bear no relationship to reality. So even if you identify them as a potential conflict, how do you call them? "Brisbane Center, Alpha Bravo Charlie, are you talking to Crunchie who's doing airwork south of Dalby?" :ugh:

Here's a snippet from SEQld right now. Crunchie and Arch are out and about, someone with no callsign (Unknown) is tooling around Caboolture and there's a Dash-8 in the mix too.

So how do you address Crunchie or Arch? Are they in a Drifter or a Diamond? Doing circuits or airwork in the area or a low-level NavEx? Neither have got an active flightplan in the app so you don't know what their lateral track is going to be nor can you infer they're on a cross-country so will be climbing to altitude and staying high. At least the Dash-8 Driver has his plan showing so you know where he's going and that he might be an issueif you're also going to Chinchilla.
https://cimg2.ibsrv.net/gimg/pprune....e482328017.jpg

43Inches 7th Apr 2022 21:35

As far as I'm aware most airlines will require EFBs to be in 'flight mode' while airborne, so the chance of seeing Ozrunways airliners will be rare, until they move into the modern era and stop using drums for advanced communication. As for how you address the unknowns, well, if they call themselves Crunchie or Arch, try that over the radio. If not "Traffic approximately 10 miles north of Flinton at 1000 ft what are you intentions" or something like that.... If center sees you on screen and need to communicate they will use your ADSB tag if no one answers a call, have heard them do it numerous times and pass on the tag information to IFR traffic to try to contact, with the provision it is just a squawk tag.

Ironpot 8th Apr 2022 02:43


Originally Posted by 43Inches (Post 11211932)
TCAS is designed to highlight conflicts, alert the crew and display a position to assist the crew in visual acquisition of the target. The closer you get to a conflict the more accurate the picture becomes, at range its not highly accurate though. However should you fail to sight the target and it gets too close, the unit will give a resolution to avoid. That's when it starts making lots of noise, things turn red etc... It is not designed to be a quasi radar scope, you can't say for sure a target is X aircraft as it does not display enough information. However that said, you can see stuff at range and then get an idea something is out there and try to communicate with it, so for situational awareness it is pretty good. I'd still separate by a safe margin altitude, track, distance, but you can use TCAS to see when something passes, then talk to it to get actual position to confirm clear. That then relieves constant position updating and radio clutter. eg " XXX I'll maintain 6000, you stay at 5000" then watch it pass on TCAS, "XXX whats your current Distance and track", (XXX responds with a GPS distance and track away from you), "XXX all clear, see ya later" or whatever.... Good thing is if either party stuffs up the TCAS will show it happening and you can query them and get ready for avoiding action.


... whereas ADSB IN displayed on the MFD will show, accurately, the position and current track of equipped aircraft. It starts to send audible warnings when altitudes approach 1000' and is particularly handy when you are on a reciprocal track.

Dick Smith 8th Apr 2022 07:39

Do all ADSB "in" units give an audible warning?

tossbag 8th Apr 2022 07:57

I would imagine that you could configure any PFD for audible warnings.

Squawk7700 8th Apr 2022 08:48

One of the main EFB’s has them and for the other, it’s coming soon.

mikewil 9th Apr 2022 01:20

Do any TCAS systems use ADSB inputs or is it still all mode C based?

OZBUSDRIVER 9th Apr 2022 05:50

MW, TCAS receives the Mode S portion of the ADS-B transponder.

Dick Smith 9th Apr 2022 06:09

But does it transmit a signal so that TCAS will work in an airline aircraft which does not have ADSB in.

esreverlluf 10th Apr 2022 02:34

I'm sure the Jizzler 700 comes fully equipped with TCAS II and ADS-B as standard.

Also - can someone please post a photo of a Jizzler 700 so I know what to look out for next time I have to go to Ballina.

Lead Balloon 10th Apr 2022 03:44


Originally Posted by esreverlluf (Post 11213199)
I'm sure the Jizzler 700 comes fully equipped with TCAS II and ADS-B as standard.

Also - can someone please post a photo of a Jizzler 700 so I know what to look out for next time I have to go to Ballina.

Jizzler 700A (nosewheel variant) during taxi trials:

esreverlluf 10th Apr 2022 08:51


Originally Posted by Lead Balloon (Post 11213212)
Jizzler 700A (nosewheel variant) during taxi trials: https://youtu.be/TWOyM9Axn-w

Thanks for that - I'm sure I'll know what it is if I see one now. Looks like quite a machine.

cogwheel 4th Jun 2022 10:42

The airspace proposal for Ballina has now bounced around CASA & ASA for some time and this is the result....


New radio frequencies are being introduced to ease congestion and increase safety around Ballina, Lismore, Casino and Evans Head aerodromes.

From 16 June 2022 the following Common Traffic Advisory Frequency (CTAF) will apply in these vicinities:
  • Ballina – 124.2 MHz (no change)
  • Lismore and Casino – 132.45 MHz
  • Evans Head – Multicom CTAF of 126.7 MHz

there is very little comment on this change elsewhere in what I can find on the web etc.

there was a proposal for a class D tower floating around, but seems ASA don’t want to pay for it and obviously some senior manager/s in CASA don’t seem to want to push it. I just hope there is a good safety case for this proposal.

tossbag 5th Jun 2022 02:44

Am I right in saying that Lismore is underneath one of the Ballina RNP's? But now on separate frequencies. That sounds smart.

Chronic Snoozer 5th Jun 2022 04:43

See and avoid mate. :ooh: (AKA Note and collide visually)

MechEngr 5th Jun 2022 07:49

Something I did not see mentioned in the above is that ADSB Out doesn't have to originate with the aircraft. If there is primary radar coverage of an area the radar operator can broadcast an ADSB message that identifies a Jizzler 700 (et al) with location, altitude, and airspeed. This also applies to balloons, ultralights, powered parachutes, and other small aircraft that (at least in the US) may be prohibited from broadcasting ADSB messages. When even airport service vehicles can have ADSB Out it's a shame it's not more widely used.

What is stunning is how easy ADSB In is - xjet in New Zealand built his own system for safer operation of drones and remotely controlled airplanes. RasPi, small display, and an SDR (Software Defined Radio module) - maybe $100-200 USD? Chip availability may have component limiting effects for the time being.

and not the only one,

Lead Balloon 5th Jun 2022 08:12

I built one of the Stratux ones. Amazing thing is how many (even high level RPT aircraft) you can spot visually, with the aid of the output of the unit displayed on the EFB screen. None of those high level aircraft is a collision risk - very ‘high’ while us nobodies are very ‘low’ - but it does demonstrate that the unit picks up and provides pretty accurate information about aircraft putting out Mode C data.

But the ‘blindspot’ is that it requires ‘something’ to be interrogating the other aircraft’s transponder….

Squawk7700 5th Jun 2022 12:24


Originally Posted by Lead Balloon (Post 11241027)

But the ‘blindspot’ is that it requires ‘something’ to be interrogating the other aircraft’s transponder….

Are you certain about that for ADSB units? I’ve been reading a lot about ADSB since fitting a new transponder last week and I hadn’t thought about that. I know that’s how Mode C works and the issues with TCAS versus PCAS but experience tells me that even a skyecho can be detected by another skyecho when not in range of a ground ADSB station and they don’t have a mode Charlie to be interrogated by radar, unless somehow it’s being interrogated by something that I’m not aware of.

I’m finding ADSB is generally not well understood by pilots. For example I keep hearing statements like “I know my ADSB is working because ATC knew my callsign” from pilots not realising that they are equipped with Mode-S transponders. I also understand that close to Melbourne and Sydney for example, that ATC see only Mode C/S and that ADSB is only visible to them outside of primary radar coverage. Moorabbin for example told me that they don’t have ADSB at all.

If anyone knows more specifics about what the controller sees, I would love to hear more. I also understand that some gps inputs are approved and some are certified and the ATC can see both, however they appear as grey for ADSB 2020 approved and green for certified, and of course only outside of traditional mode C/S radar coverage.




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