Aircraft not showing on the map

Want to post something that doesn't quite fit into the other forums? This is the place for that.
Post Reply
philhyde
Posts: 7
Joined: Tue Oct 13, 2015 7:26 pm

Aircraft not showing on the map

Post by philhyde » Thu Nov 19, 2015 6:14 pm

Hi there,

Bit of a newbie question, but I'm wondering what determines whether aircraft show on the map or not? Is it signal quality, or aircraft not broadcasting their location?

I participate in another exchange group, where a shared VRS map shows military aircraft in my location (not MLAT), but I have never mapped a single one.

Thanks for any feedback!

cheers,
Phil

Me109
Posts: 37
Joined: Sat Nov 01, 2014 4:54 pm
Location: KORH

Re: Aircraft not showing on the map

Post by Me109 » Thu Nov 19, 2015 9:04 pm

Many/most .mil use Mode-3A/C, so the position data isn't broadcast (ICAO hex, altitude, call sign) and therefore you'd see those aircraft identified in the list but not shown on the map. Using MLAT allows the position to be derived by the receivers that are detecting that transponder.

If you're using a shared VRS map, it may be that you're not doing MLAT, but people in your area feeding the exchange are, and therefore you never map those local Mode-C tracks.

Some .mil aircraft are ADS-B, I think the E-4s and E-3s are for example, many of the State Dept./logistics fleet (C-32, C-40), while others are under upgrade to add it (KC-10).

philhyde
Posts: 7
Joined: Tue Oct 13, 2015 7:26 pm

Re: Aircraft not showing on the map

Post by philhyde » Sat Nov 21, 2015 5:30 am

Thanks for the info!

Post Reply