Originally Posted by
wealthysoup
Indeed, it is called multilateration - unfortunately a term that a lot of people aren't familiar with.
Where does the accuracy of 50m for x,y,z come from? I've never heard of a specific accuracy for FR24 but would be interested to know if its implentation of MLAT really is that accurate.
I'm afraid that the "radar site" getting time and position from a GPS attached to the receiver is outdated by several years. Whilst a GPS can be used, flightradar allows users to enter X,Y and Z of their receiver (or more specifically their antenna) without ever having to connect to a GPS. If the GPS was (still) a requirement then the data would likely be a fair bit more reliable.
Edit: Just googled - Here is the official accuracy statement for MLAT from the flightradar blog: "MLAT position calculations have a general accuracy of 10-100 meters and 1000 meters in the worst cases."
We are talking about utility non professional service,
which is not certified,
have no intention to be navigational aid,
just for informational use,
etc....
On the other hand that area is have fair coverage with F- kind of FR24 hardware where GPS is ON 7/24/365 and position can not be "written by
hand" and time domain timing is not estimated through network but sourced from GPS timing.
Which is slight difference to T- kind of devices mostly self home-made out of good SDRdongle, RPI2or3, fair 1 GHz range antenna, good net, with or without GPS present.
Here, have both and experience of more than 4 years of 24/7/365 monitoring is that accuracy of MLAT on S type of transponders is within
20 m range. There are also several other pilot implementations of similar time domain MLAT technology for example in SAR use. Have some
experience on that too.
Let's see official report but expect no surprise, the plank was above
and behind on 7 to 8 diving on poor souls in G2
Edit / this post just confirm that the data for FR24 was enough to have fair estimation of position:
Originally Posted by
ATCO Fred
Sadly I watched this accident on radar . . . . both Mode S equipped squawking A and C.