ATC tracking websites

[goldox]

As I often work at Henley I get loads of Heathrow inbound traffic overhead. I use various tracking websites to monitor the traffic, such as the excellent www.Flightradar24.com and www.lhr-lgw.com (Live movements section).

I have noticed when using these sites, that the results sometimes "disagree"; but I was of the opinion (wrongly?) that they were receiving the same ACARS information and just displaying it in a different format.

For instance today, flightradar24 showed an Air Canada flight inbound, but the lhr-lgw report did not record it? There was an earlier Air Canada flight recorded but with a different Registration. Could it have been wrong?

So, if these systems are reporting the air traffic 100% accurately, what happened to the second Air Canada flight that "disappeared"?

As I say, I maybe making a huge assumption here about what information is transmitted/recorded!

Thanx in advance for any replies and information.

[sprthompson]

My girlfriend is cabin crew and being the geek I am I like to track her flights.

Quite a few of these sites delay the data they show for security purposes, which may be one reason they disagree,

openATC - quite good, limited coverage, quite a delay in data.
AirNav RadarBox - Screen Shot refreshed Every minute - London aread

RadarVirtuel.com - My latest find and favourite so far covers a lot of area and gives plenty of data - some of the data seems to show planes taxing around LHR.

This one shows data from the last 100 aircraft on final approach.. - 100 most recent arrivals to Heathrow | Heathrow Airport Information

[raffele]

There's more here

http://www.pprune.org/spectators-bal...cker-ever.html

All tracking sites delay the data, usually by between 5 and 15 minutes. It would otherwise provide a very valuable tool for those with malicious intent.

[goldox]

Many thanx to you both. I did not realise just how many varied tracking sites there were.

As you say delays in information being broadcast may explain missing data, and I can look back at the lhr-lgw logs in a couple of days to see the full reports.

[sprthompson]

What is the right URL for that lhr lgw site? The one you posted originally doesn't appear to work?

[caiman27]

I don't think that RadarVirtuel has much of a delay, if any. If I hear a particularly noisy takeoff when I'm sat here in Stortford, it almost immediately shows a 747 heading off.

But it is no use for old aircraft or bizjets, or, I suspect, Russians.

By the way, I got so bored with IE 7 problems with RadarVirtuel that I decided to give Chrome a trial. I have not switched back...

[HEATHROW DIRECTOR]

On-line tracking sites are of little use if you want real-time info. One of the SBS-type gadgets does the trick, with no delay in displayed information.

[goldox]

sprthompson: Apologies typing too fast and not thinking!
It's: www.lhr-lgw.co.uk

Heathrow Director:
Thanx for that I was considering getting my own but my budget has been a bit hammered by Xmas and son's wedding!

caiman27: yes I have been using Chrome a lot as well. What's the porblem with old/Russian aircraft (not) sendn data?

[HEATHROW DIRECTOR]

...simply that the carriage of ADS-B is not mandatory in UK airspace.

[konsult]

You can find lists of common aircrafts that are visible, and not visible on the "radar" on http://www.flightradar24.com/about.php

[HEATHROW DIRECTOR]

I'm not sure how flightradar24 functions and I'm just watching it for the first time. It's currently showing two aircraft in the London TMA whereas my SBS is showing 50+ in the TMA out of 113 total over the UK. I guess flightradar24 has to be set up somehow, but I'm not aware of how to do that.

[goldox]

Thanx Konsult.

If I had looked at this link earlier I would have realised why the Embraers that fly over my house are never on FlightRadar24!

Also explains why the rather large IranAir 747 into Heathrow yesterday lunchtime didn't show up! But where was the Virgin A340 following close behind?

[HEATHROW DIRECTOR]

Interesting... I've not yet seen a Virgin A340 which hasn't shown up on ADS-B. Maybe it was a tech snag?

[Betablockeruk]

Casper has introduced feeds for Manchester and Dublin with the offer of 'realtime' for subscribers ( a few euros per month). Otherwise 15 min delay.

Love the replay utility.


Casper - Live Aircraft Tracking

[Groundloop]

Maybe someone should tell Casper that whoever is providing the UK feeds is breaking the law.

[MikeBanahan]

How flightradar24 operates

I'm not sure how flightradar24 functions and I'm just watching it for the first time. It's currently showing two aircraft in the London TMA whereas my SBS is showing 50+ in the TMA out of 113 total over the UK. I guess flightradar24 has to be set up somehow, but I'm not aware of how to do that.

I did some lengthy investigation of the various ADS-B receivers out there on the market and how they can be used. Since I haven't actually done this, don't count what I say as authoritative but I believe I'm approximately right.

Sites like flightradar24 and radarvirtuel rely on volunteers with ADS-B receivers to cooperate via permanently-on connections to the internet. Those sites aggregate ADS-B information from the volunteers and then present it graphically. They will have different sets of volunteers in different locations with different reception coverage, which accounts for different aircraft showing. Also not all volunteers leave their receivers online all the time.

What you see is what information they have aggregated at that moment, not necessarily a complete representation of the aircraft actually out there.