IGRID vs Mode S 3D

[a.alexeev.p]

Hi,

i have been looking through the knowledge base and was not able to find an answer unfortunately for the following questions:

1) say I use iGrid, but have Mode S3D disabled… what happens then to the MLAT aircraft that are detected by iGrid, but not by my onboard PAW? What about MLAT aircraft that detected by iGrid, but also by my onboard PAW as bearingless?

2) same as above, but I have Mode S3D enabled.. do I get it right that the system will try to plot the most accurate one?

3) last, but not least: does anybody know if SkyDemon draws circles of ambiguity for ModeS3D or it just plots an MLAT aircraft in the same way as any other?

Many thanks for any help or hints:)

[exfirepro]

Hi Alex,

Re 1) and 2), I can’t answer definitively, but pre iGRID, if Mode-S 3D was disabled, PAW would only send bearingless Mode S data to the EFB (assuming it was being received by your PAW). So if data was NOT being received by your PAW directly, you would get NO WARNING.

I would presume the same would apply to iGRID - as the only difference (as I understand it) is the way the position data is sent to PAW - i.e. via ATOM or GSM.

That said why anyone would want to deliberately disable Mode-S 3D in favour of bearingless warnings only, I can’t imagine.

Re 3), SkyDemon stopped displaying ambiguity circles for MLAT aircraft a long time ago as it was causing issues with another EC device. They just display the aircraft where the EC system says it is irrespective of which EC device is in use (not naming names as I don’t want to start yet another war!).

Regards

Peter

[a.alexeev.p]

Hi Peter,

Thanks a lot for your reply! I have finally properly tested the system at home, and I am pretty sure I was seeing aircraft that weren't in range of the actual PAW. So, I guess PAW system should somehow just try to plot the most up to date location (GSM or direct from ATOM).

I used to have 3D disabled due to all the precautions that were posted about it, so I thought I would be safer looking out 360 degrees rather than look for exact location, but in a slightly wrong direction :-D

Best wishes,
Alex

[a.alexeev.p]

One thing I was experiencing yesterday when again testing at home – in home page I could see hotspot connected and iGrid identified, but no G traffic in traffic screen and orange GS< tab in radar screen. Normally it means hotspot connection, but no internet... I was 100% sure internet was there and working (also tried home WiFi) without much luck. 30 minutes later it started working without any changes on my side...

Any idea what it might have been the reason?

On the original question, still would really appreciate if Admins could advise if I get iGrid MLAT aircraft shown to me as normal (in radar tab and in SD) even if Mode S 3D is disabled?

[Admin]

There is a public/private key exchange at first connection
But this should not take 30 minutes
Can you confirm it was really this long ?
Thx
Lee

[a.alexeev.p]

in screenshot above uptime is 15 minutes and it shows connected, but no traffic... so GSM was orange. I was not watching it closely non-stop, so may be it started working on minute 16, but still a lot even if so... I was doing work meanwhile, so 20-30 minutes till I noticed it actually working for sure

PS
On the original question, still would really appreciate if Admins could advise if I get iGrid MLAT aircraft shown to me as normal (in radar tab and in SD) even if Mode S 3D is disabled?

[Admin]

On the original question, still would really appreciate if Admins could advise if I get iGrid MLAT aircraft shown to me as normal (in radar tab and in SD) even if Mode S 3D is disabled?

Need to double check, but I think you possibly do

[Admin]

Hi Alex

I just had a thought on this.
What do you have your "Aircraft Transmit Speed" set to ?

If I recall correctly, I think we only send data to you when you are sending data (position reports) to us,

Thx
Lee

[a.alexeev.p]

Hi Alex

I just had a thought on this.
What do you have your "Aircraft Transmit Speed" set to ?

If I recall correctly, I think we only send data to you when you are sending data (position reports) to us,

Thx
Lee

Hi Lee,

Not tested in an aircraft yet, but at home in comfort and all is working regardless of the set speed. I used to have it at 0, but now put to 30 kts. Although not quite sure how it might be connected to the question?

[Admin]

in screenshot above uptime is 15 minutes and it shows connected, but no traffic... so GSM was orange

Referring to this message

[PaulSS]

What do you have your "Aircraft Transmit Speed" set to ?

If I recall correctly, I think we only send data to you when you are sending data (position reports) to us,

Hi Lee,

Bearing in mind I am asking this question in the context of iGrid v Mode S 3D:

Does that mean if I have it set to 20kts I won't receive any PAW alerts until 20kts or is it only GSM data I won't receive? Obviously I will not transmit data until 20kts.

[a.alexeev.p]

in screenshot above uptime is 15 minutes and it shows connected, but no traffic... so GSM was orange

Referring to this message

Wouldn’t remember unfortunately… might have as well changed it since then. But thing is I didn’t start moving and didn’t change that setting at that time, yet it started working, but just after a while

[Admin]

What do you have your "Aircraft Transmit Speed" set to ?

If I recall correctly, I think we only send data to you when you are sending data (position reports) to us,

Hi Lee,

Bearing in mind I am asking this question in the context of iGrid v Mode S 3D:

Does that mean if I have it set to 20kts I won't receive any PAW alerts until 20kts or is it only GSM data I won't receive? Obviously I will not transmit data until 20kts.

Need to double check
Thx
Lee

[exfirepro]

Lee / Paul,

I still get audio alerts when stationery with my VSO set to the default 10Kts (e.g. while doing pre-flight checks), but no idea as to the mechanism. I would presume from direct reception, but no easy way to tell without monitoring the Traffic Screen - and even then, not sure it would be definitive.

Best Regards
Peter

[PaulSS]

That’s what I was thinking, Peter, but I thought J would ask the ‘open’ question in case I’d got it wrong again. I THINK it receives all the time but doesn’t transmit until the speed set in the box.