dump1090: Why don't all the planes show on my map view?

Running dump1090 with piaware.

When I browser view port :8080 I often see several planes that are not plotted on my map. However, I can head over to flightradar24.com/ and see that these same planes are being plotted on that sites map. I know it is the same plane due to the same squawk (if you want to tell me what that number means I take that answer as well :question: ) or tail number.

Why is my rig not plotting the location for all the planes that it sees? :question:

Thanks.

Is the plane on FlightAware.com as well? An example would be great.

Okay. An example… That’s easy. See screenshots of each of the three examples below.

  1. My RasPI is “seeing” squawk 2557 so I know that it is in my antenna coverage. Why is it not on my map? :question:
  2. Head over to Flightradar24. I see squawk 2557, but it is also plotted on the map, so I know LONG/LAT has to be available (I guess).
  3. Head over to FlightAware map. It also sees the plane AND plots it on the map.

So… why is it not on my local RasPI :8080 map? :question:

Local RasPI dump1090:8080 screenshot


Flightradar24 screenshot

FlightAware screenshot

The aircraft is not ADS-B equipped. You are receiving Mode S only data, which has the squawk and altitude but no latitude/longitude. Currently, FlightAware is tracking AAL1296 using FAA RADAR data only.

if fr24 can mlat it, it will show you and say so. if you check the graph for that flight if it is ads-b equipped or if the data is coming from an faa or alternate feed it will say Oakland Center or wherever the nearest center is.

which brings me to another question: do you guys have enough equipment to mlat?

Great explaination. I’m new to the application, vocabulary, etc.
Thanks for the help.