Aircraft showing in list but not on map

[Burnley]

I've noticed that some aircraft show in my list, but not on the map.  Is this for security reasons?

I'm assuming it is as they seem to either be UK or USA Military or Police that I can't see.

I keep seeing this one belonging to Greater Manchester Police: G-GMPB - Britten Norman BN2T-4S Islander.

[Aerotower]

No, it's just because the aircraft is equipped with a transponder mode-S, but do not report their position (without ADS-B).

[Burnley]

No, it's just because the aircraft is equipped with a transponder mode-S, but do not report their position (without ADS-B).

Ah ok, thanks for that.

[bratters]

No, it's just because the aircraft is equipped with a transponder mode-S, but do not report their position (without ADS-B).

Is it just my imagination or are there now considerably more aircraft not using ADS-B?

I've currently got shedloads of BA, Lufthansa, Ryanair, Easyjet, Thomson, Shuttle etc in MyFlights but not showing on the map. I seem to recall that in the past that most of these European carriers gave positional information - maybe I'm just having a senior moment.

[Burnley]

No, it's just because the aircraft is equipped with a transponder mode-S, but do not report their position (without ADS-B).

Is it just my imagination or are there now considerably more aircraft not using ADS-B?

I've currently got shedloads of BA, Lufthansa, Ryanair, Easyjet, Thomson, Shuttle etc in MyFlights but not showing on the map. I seem to recall that in the past that most of these European carriers gave positional information - maybe I'm just having a senior moment.

I'm getting the same thing for a number of aircraft now.  Aircraft showing on my lists, but nothing on the map.  I hope it's not something new that's coming into force.  Just bought my RadarBox!

[AirNav Support]

The stats show more aircraft are getting ADS-B, especially in Europe. Network which only shows ADS-B has been getting bussier as well since we first start even if you ignore the rise in RadarBoxes feeding it.

[Runway 31]

Burnely,

ADSB equipped aircraft dont show on the map all the time depending on your actual coverage.  While they will show in Myflights it doesnt necessarily mean that the will show on the map at the same time. 

I dont know the technecalities of it, something to do with the differences between mode-s and ADSB.  The receiver may be picking up the mode-s signal being sent by the aircraft but may not be receiving the ADSB signal.  Some factors can block the ADSB signal but still allow the mode-s signal to be received.

Hopefully someone with greater understanding than myself can explain a bit better.

Alan

[AirNav Support]

In a simple way the Mode-S signal is smaller than a ADS-B singal so the Mode-S signal is less subject to distortion, hence if an aircraft is just in your coverage you will get the Mode-S signals but not the ADS-B untill the singal is stronger.

[Burnley]

Thanks for clearing that up.  Apart from the odd aircraft, i'm happy with what i've got and see on the normal aerial in my room.  I live between hills and the range is damn good in my opinion so I can't complain about odd signals being lost.