Why are so often flights missing on flightaware website?


i only feed flightaware but what i find very disappointing is that sooo often i have flights where my site does mlat and can’f find them on flightaware website - but nearly ever find them immediately on fr24 website. and honestly the fr24 website in most aspects is by far the better one …

see picture:


You mean this flight? https://flightaware.com/live/flight/DEDVZ/history/20170829/1213Z


yes exactly that was what i got while the aircraft was near my house. i saw it in skyview but i wonder why all the the part in my range was/is missing?


What is “all the part in your range”? The flight is present, I’m not sure what the issue is here.


if i follow your link above this is what i get and similar to what i got when i made the post - and it shows just a small part of the flight i can see in fr24 - and saw on my raspi-skyview while the plane was in the air. that’s what i do not understand and what happens frequently …


It’s not surprising that FlightAware and FR24 have different mlat coverage, since they’re using different sets of receivers. For example, here’s an earlier section of (probably) the same flight that FlightAware has, but which is not present in your FR24 screenshot: https://flightaware.com/live/flight/DEDVZ/history/20170829/0934Z

If that’s not what you mean, please explain the problem more clearly.


ok - sorry - always a bit harder in a foreign language. you are fully right they have their sites and fa has other sites so sometimes fr24 or fa can track and mlat - sometimes both.

the thing i do not understand is: if i sit in front of my skyview and see huge parts of the track that fr24 shows i just can see it because fa is doing mlat (partly with my actual data) but i cant see the flight on the flightaware website?

hmmmm - hope you understand what i mean …

here in the picture at least this was the part fa and i made mlat - but this part did not show up on website

maybe im too daft to use the fa online website … but just don’t know


now queried my mysql database for the hex number and time-slot about 5 hours ago there i have more than 2000 datasets all with position and filled mlat-array. and this data i never had without fa -> so fa must have the data too -> but big parts of the flight i did not find on fa website?


Not all mlat positions automatically appear as part of a flight.

If there is an existing flight (and no higher-priority datasource) then generally they will get associated with that flight.

In cases where mlat is the only datasource we have for an aircraft (e.g. no schedule or IFR/flightplan information) then we are very conservative about inferring a departure and creating a new flight from mlat data only. In this case it’s likely that the conditions to do that weren’t met for a while.


ok - got it. for me it’s not a problem at all as i have skyview to see the flight anyways - just thought that it would be nicer if the data where my site helped to harvest would be more helpful for fa. i looked in the history of this aircraft for today on fa website but the only legs i found were the two you and i mentioned already above - so the biggest part of todays flight(s) from this aircraft were harvested but do not show up. i just thought there were a bug on the fa-website-frontend that loses the gathered data from mlat-server. at least it was not just that i was too dumb to use the fa website :smiley: thanx for reply