MLAT is now live on Flightradar24

[everton_cwb]

Nice! At least show registration instead of 'unknown'!

I set my FR to show only the registration but I see an "Unknown" tag on an Azul's E190. There's no reg, but there are the Hex Code (E48D42) and a picture of the aircraft.

[Oblivian]

I set my FR to show only the registration but I see an "Unknown" tag on an Azul's E190. There's no reg, but there are the Hex Code (E48D42) and a picture of the aircraft.

Need an eyes-on view of it, confirm registration and request it to be added to database in the request thread.

The usual search engines do not confirm the registration matching the HEX

This goes for entire fleets of aircraft. If MLAT is the first contact by FR24 servers, the list needs to have them added before information is shown.

[Jarod]

F-EHRD3 is now enabled.
4 FR24 receivers on a very small area. Any reason for this?

Update MLAT around Schiphol:
F-EHAM1 <-- ground level reception
F-EHAM2 <-- ground level reception
F-EHBK1 <-- south/east of eham, outside TMA reception
F-EHEH1 <-- south/east of eham, inside TMA reception
F-EHGG1 <-- north/east of eham, outside TMA reception
F-EHGG2 <-- north/east of eham, outside TMA reception
F-EHKD1 <-- north of eham, short final reception
F-EHRD1 <-- south/west of eham, short final reception
F-EHRD2 <-- south/west of eham, short final reception
F-EHRD3 <-- south/west of eham, short final reception
F-EHTW1 <-- east of eham, inside TMA reception
F-EHVB1 <-- south/west of eham, ground level/short final reception

bold = MLAT at low level around Schiphol.

(F-EHRD3 and F-EHEH1[forgotten last time] added)

[Happpy]

Very cool to have more MLAT showing.
Just need to work on getting the Australia and Brazil and United States on MLAT


List of active MLAT receivers turned online for MLATing:
F-EGTK1/Oxford, GB - MLAT active
F-EETN2/Tallinn, EE - MLAT active
F-EGSH1/Norwich, GB - MLAT active
F-EPSU1 Elk (North East Poland) - (will be MLAT)
F-EPKK1 Bochnia (Southern Poland) - (will be MLAT)
F-LIMC1/Milan, IT - Will be added to MLAT later
F-EVRA2 - Riga, Latvia (MLAT upgrade)
F-EKYT1 - Aalborg, Denmark will be upgraded from ADS-B to MLAT
F-EGHD1/Plymouth, GB in UK - with MLAT
F-EHRD1/Rotterdam, NL in Netherlands - with MLAT
F-EGNX2/East Midlands, GB in UK - with MLAT
F-UKLL1/Lviv, UA in Ukraine - with MLAT
F-EFHK3/Helsinki, FI in Finland - with MLAT
F-ENAL1/Alesund, NO in Norway - with MLAT
F-LKTB1/Brno, CZ in Czech Republic - with MLAT
F-EGNR2/HAWARDEN, GB in UK - with MLAT
F-EFHK2/Helsinki, FI in Finland - with MLAT

Why MLAT should only be at Australia, Brazil and US? Why not in Pakistan?
I reckon Pakistan has more than 4 ADS-B receivers. Am I right? If it's then why MLAT isn't in Pakistan so far?

[Amper]

4 MLAT receivers receiving info from THE SAME PLANE, not in the same COUNTRY

MLAT
In some regions with coverage from several FR24-receivers we also calculate positions of aircraft with the help of Multilateration (MLAT), by using a method known as Time Difference of Arrival (TDOA). By measuring the difference in time to receive the signal from aircraft with an older ModeS-transponder, it's possible to calculate the position of these aircraft. Four FR24-receivers or more, receiving signals from the same aircraft, are needed to make MLAT work. That means that MLAT coverage can only be achieved above about 10000-20000 feet as the probability that signal can be received by four or more receivers increases with increased altitude.

MLAT coverage is today limited to some parts of Europe and North America, but expanding to parts of Australia and Brazil in March 2014.

[awgawg]

I have a MLAT query. It appears that a number of smaller commuter aircraft (SAAB340) more readily appear as MLAT in my area (northern Scotland/F-EGQS1) whereas larger aircraft are identified by individual receivers. Can anyone explain why?

The smaller MLAT aircraft can fly directly overhead (within 10NM) sometimes do not show up as local traffic on the Premium Radar View and disappear from FR24 even though they should be within my coverage. Is this a known issue?

[Amper]

MLAT covers MODE-S equiped-only planes. ADS-B equiped planes are covered with single radar. http://www.flightradar24.com/how-it-works
Only ADS-B planes are shown as "local traffic"

[awgawg]

MLAT covers MODE-S equiped-only planes. ADS-B equiped planes are covered with single radar. http://www.flightradar24.com/how-it-works
Only ADS-B planes are shown as "local traffic"

Thank you. That explains why MLATs keep disappearing in my sparsely populated area.

[Jarod]

I think I have found the answer. 3 of our strongest receivers ever were activated this weekend.



Also Belfast activated earlier last week have very, very good coverage.
Aircraft and helicopters flying on 1000 feet are now a common view in some parts of Europe.

Mike can you reveal to us what totally crazy coverage means range wise?
Of course this presents a challenge.

[Ratty]

MLAT covers MODE-S equiped-only planes. ADS-B equiped planes are covered with single radar. http://www.flightradar24.com/how-it-works
Only ADS-B planes are shown as "local traffic"

This reason is that M-LAT is not computed inside the receiver.
Every M-LAT capable receiver only samples the signal and sends it to some server along with a very precise timestamp and the receivers position. From there the server analyses the signal and tries to spot "similar shapes" in the signal.Then, using the timestamp that was uploaded along with the signal and the position of the receiver the server it is capable of calculating from where the signal was sent. This is why you need at least 4 receivers to determine.
I know professional systems which are capable of up to 20m precision using this technique.
If you want to know the math behing it : http://en.wikipedia.org/wiki/Multilateration

[Amper]

This reason is that M-LAT is not computed inside the receiver.
Every M-LAT capable receiver only samples the signal and sends it to some server along with a very precise timestamp and the receivers position. From there the server analyses the signal and tries to spot "similar shapes" in the signal.Then, using the timestamp that was uploaded along with the signal and the position of the receiver the server it is capable of calculating from where the signal was sent. This is why you need at least 4 receivers to determine.
I know professional systems which are capable of up to 20m precision using this technique.
If you want to know the math behing it : http://en.wikipedia.org/wiki/Multilateration

What did I say wrong?

QUESTION:

I have a MLAT query. It appears that a number of smaller commuter aircraft (SAAB340) more readily appear as MLAT in my area (northern Scotland/F-EGQS1) whereas larger aircraft are identified by individual receivers. Can anyone explain why?

The smaller MLAT aircraft can fly directly overhead (within 10NM) sometimes do not show up as local traffic on the Premium Radar View and disappear from FR24 even though they should be within my coverage. Is this a known issue?

ANSWER:

MLAT covers MODE-S equiped-only planes. ADS-B equiped planes are covered with single radar. http://www.flightradar24.com/how-it-works
Only ADS-B planes are shown as "local traffic"

If you want to show your knowlege, be my guest, but don't quote my simplified and correct answer. Written so anyone can understand. I know how MLAT works, but did't find appropriate to quote half of wikipedia.

[Ratty]

If you want to show your knowlege, be my guest, but don't quote my simplified and correct answer. Written so anyone can understand. I know how MLAT works, but did't find appropriate to quote half of wikipedia.

Well I never ever to show off nor said you were wrong nor meant to explain to only YOU how MLAT works and nither did I quote Wikipedia...
I just wanted to developp your simple answer getting in more details, trying to explain it a litlle more simpler than the wiki article. BTW You just said that MLAT traffic is not shown as "local traffic" you did not explain why.
Just trying to help the user who had the original question. If trying to expand simple yet correct answers ends up in being flamed, well ..... nevermind...

[SoCalBrian]

Please, no fighting!

Interesting information for the other readers on the forum.
Let's not get this thread locked by some mods.

[Ratty]

Please, no fighting!

Interesting information for the other readers on the forum.
Let's not get this thread locked by some mods.

That's all said !

[SoCalBrian]

You are fine Ratty,

Just don't want to see this thread get locked.
Mike uses this thread to tell us MLAT updates/news.