Radarbox is "blind" for the planes above my head

[OKC-Steve]

By this do you mean the SBS will have the same problem??

I guess I don't understand your question. Nothing described here will affect another product.

[Fenris]

Nothing has been confirmed yet. Let us fully investigate all the details.

I only meant that if the software is outputting longitude numbers that are less than -180 degrees (i.e. -214 degrees as mentioned) then it has to be a calculation error.

Either that or the world has been turned into a Klein bottle.

[shouriken]

I will paste a small part of a logged flight:

MSG,1,0,0,4A0663,0,2009.11.19,17:34:48.453,2009.11.19,17:39:48.453,ROT373,,,,,,,,,,,
MSG,3,0,0,4A0663,0,2009.11.19,17:34:48.453,2009.11.19,17:39:48.453,,1900,,,44.5867,-333.8703,,,,,,

MSG,3,0,0,4A0663,0,2009.11.19,17:39:44.156,2009.11.19,17:44:44.156,,13925,,,44.7476,-334.2863,,,,,,
MSG,3,0,0,4A0663,0,2009.11.19,17:39:44.156,2009.11.19,17:44:44.156,,13950,,,44.7480,25.7127,,,,,,

The flight started to get tracked in ANRB at 17:39:45 ( local time) when the longitude became 25.7127
Notice that 360-334.2863=25.7137

Liviu

[tarbat]

This looks like it might be location specific.

I left SBSSIM recording all port 30003 output today.  Imported into Excel, sorted by LAT and then by LONG, and all lat/long values are valid, in the range:

LAT : 54.7957 to 58.9588
LONG: -8.2794 to +0.6318

That's out of 112,000 lines of port 30003 output.

[Fenris]

Yes, and I'm certain that the ADS-B frame doesn't allow for greater than 180 or less than -180 degrees of longitude, so it was not transmitted like that.

This is almost certainly location specific Tarbat, if it weren't then it would have been found and fixed some time ago as the level of complaints would be much higher. It may be a combination of home location and aircraft position.

If the person concerned is the only sharer on the network, I wonder where these aircraft would show up? Possibly the server rejects them as being in impossible places ;-)

[DaveReid]

Yes, and I'm certain that the ADS-B frame doesn't allow for greater than 180 or less than -180 degrees of longitude, so it was not transmitted like that.

Indeed not, although latitude and longitude aren't sent explicitly - instead, they are encoded using the CPR algorithm based on 360nm cells, and decoding is by no means a trivial exercise so it's quite conceivable that a bug has crept into the process.

[AirNav Development]

We would ask all users reporting this problem to send us a PM so we can contact them directly with a new exe ready for testing.

[OKC-Steve]

Don't forget to fix the socket output as well:  The last 4 values are boolean, so they must be either 0 or -1, and not null.

FYI

[Fenris]

Well, shouriken and Mike_Tassy are two of them, and it could be the reason for the problem described by the guy in NZ who had a blank rectangle near his home location, I can't remember his forum ID.

Do you want any other people to test it too?

[AirNav Development]

We've just Pm'ed them. Waiting for their replies.

This thread clearly shows how this forum is helpful and positive: a typical example on how users in direct contact with a company development can result in positive news for both sides.

[Fenris]

airdata is the forum ID of the NZ guy with the blank rectangle.

[Fenris]

The NZ and Aus people should be waking up about now too.

[Fenris]

vic_atc is anothe forum member with a problem of this nature

[DaveReid]

We would ask all users reporting this problem to send us a PM so we can contact them directly with a new exe ready for testing.

Presumably if affected users are sharing, you will be able to pick up invalid coordinate data on the network ?

[AirNav Development]

Dave: tks for your message. We've sent a PM to 3 of these users. We are just waiting for tehir replies. We are 99% sure the problem is now corrected. Just waiting for their feedback.