Flight Trackers

[SpringHeeledJack]

I use 3 flight trackers, one paid and the other two restricted unpaid. To assuage my sometimes compulsive need to 'find out what that was' they have been most helpful. However, as of late I've noticed that more and more non-scheduled stuff just doesn't show at all. Helicopters, biz jets, cargo and military very much affected. Why would this be all of a sudden ? Now if I were to be the owner of a private aircraft, I wouldn't want to have my movements tracked by anyone but ATC, but things are as they are and we spotters/enthusiasts/nosey parkers can do so legally. Is it that more owners are becoming savvy to the wider risks of being tracked ? Any ideas chaps ?

[DaveReidUK]

I believe that sites such as FlightRadar24 voluntarily allow aircraft owners to have details of their aircraft movements suppressed. In other words, while their ADS-B transmissions are captured by network feeders' receivers as normal, they don't get displayed on the website.

It may be that an increasing number of corporate aircraft owners are taking advantage of this facility. There is certainly no question of bizjets, helicopters, etc, suddenly stopping transmitting ADS-B where they did previously.

[KelvinD]

Things can get a bit spotty sometimes, but you need to remember, these sites (in general) rely on volunteers capturing the AIS data and forwarding it via the tinternet.
On a related topic; can anyone shed some light on how they display flight info? Eg, recently while watching newly delivered A320Neo G-TTNC heading toward Heathrow, Planefinder didn't have this aircraft in their database yet so it showed up as "No Reg", yet is still showed a BA flight from Warsaw to Heathrow, with speed, altitude, miles to go etc. So my question is how do they derive the flight info regarding airline, flight number and origin/destination?

[DaveReidUK]

On a related topic; can anyone shed some light on how they display flight info? Eg, recently while watching newly delivered A320Neo G-TTNC heading toward Heathrow, Planefinder didn't have this aircraft in their database yet so it showed up as "No Reg", yet is still showed a BA flight from Warsaw to Heathrow, with speed, altitude, miles to go etc. So my question is how do they derive the flight info regarding airline, flight number and origin/destination?

The aircraft identity is derivable from its ICAO 24-bit address but, as you saw, that relies on having an up-to-date database of tie-ups between the two.

The flight number (in the form of the ATC callsign, which may differ somewhat) is transmitted by the aircraft via both Mode S and ADS-B. That identifies the airline and, in turn, should allow the origin/destination to be derived, again assuming an up-to-date database of flight numbers vs routes.

Speed, altitude and position are transmitted by the aircraft via ADS-B. Miles-to-go, ETA, etc, will be calculated from that.

[KelvinD]

Many thanks Dave. As ever, a helpful and informative response as usual.
It has all moved on a bit since I worked with Mode S stuff years ago!

[Liffy 1M]

This site is good for military if you go into the detailed Options menu and set preferences to just show mil traffic. https://www.adsbexchange.com/

[KelvinD]

Agreed re adsbexchange. It can be tricky to get used to though if using it on your Android.

[THE AIRBOEJET]

Agreed re adsbexchange. It can be tricky to get used to though if using it on your Android.
Agree with you have to remember its where the text is for the position of the aircraft not the aircraft shape on the map

[SpringHeeledJack]

I believe that sites such as FlightRadar24 voluntarily allow aircraft owners to have details of their aircraft movements suppressed. In other words, while their ADS-B transmissions are captured by network feeders' receivers as normal, they don't get displayed on the website.

It may be that an increasing number of corporate aircraft owners are taking advantage of this facility. There is certainly no question of bizjets, helicopters, etc, suddenly stopping transmitting ADS-B where they did previously.

That appears to be the case in my experience, many still do show, but compared with some months ago greatly reduced. An example has been the last couple of days helicopter traffic between Ascot and London, loads ln the air, yet few showing up. Even ADSBexchange, which was a revelation when first used, that is now, in my experience much reduced.

[DaveReidUK]

An example has been the last couple of days helicopter traffic between Ascot and London, loads ln the air, yet few showing up. Even ADSBexchange, which was a revelation when first used, that is now, in my experience much reduced.

I'm not close enough to the business/rotary communities to know whether they have finally woken up to the fact that they can hide their aircraft movements from the general public on the tracking websites.

But looking at unfiltered Mode S data captured from here (about 10 nm from Ascot), yesterday saw around 260 helicopter movements, of which only about 10% were military. That seems about par for the course (npi).

[El Bunto]

Even ADSBexchange, which was a revelation when first used, that is now, in my experience much reduced.

As Dave mentioned it's rare for a Mode-S aircraft to stop transmitting except due to technical issues. I mentioned to a local pilot that his AS55 was no longer transmitting and he realised he hadn't re-enabled the box after maintenance.

ADSB Exchange and 360radar don't elide aircraft. If they're not showing up then they're too low for MLAT triangulation.

I wish one of the web-based trackers would provide a simple text list of positionless aircraft. PlanePlotter, a desktop program, does that along with the IDs of closest receivers which is almost as useful as knowing their exact location.