There currently is a helicopter circling over my hometown of Karlsruhe, Germany and I wanted to find out what its purpose is.

I found it on a helicopter flight tracker but it had its callsign 'blocked'.

AirNav RadarBox screenshot

I do know its departure airport and I saw that it was blue and white. Could this have been just a sightseeing flight? If so how could I find out and why was it 'blocked'?

  • 4
    $\begingroup$ Look it up, while it's flying, on adsbexchange. They don't block/filter as much. $\endgroup$ Commented Aug 10, 2022 at 15:37
  • $\begingroup$ @tedder42 ADSB Exchange doesn't block/filter anything. They are very explicit about this. $\endgroup$
    – Jeremy
    Commented Aug 11, 2022 at 14:11

2 Answers 2


Whenever you see a helicopter circling over a large city in Germany, it is most likely a police helicopter.

The helicopter took off from Baden-Airpark (Flughafen Karlsruhe/Baden-Baden FKB), where one of the police helicopters of the state of Baden-Württemberg is stationed:

Police helicopters take off from the Baden Airpark in Rheinmünster for operations throughout Baden-Württemberg

One of six police helicopters in Baden-Württemberg is stationed at the Baden Airpark in Rheinmünster. An onboard thermal imaging camera helps search for missing persons and criminals. [...]

Police Helicopter

(Badische Neueste Nachrichten, bnn.de, translated by Google)

The colour also matches your description of "blue and white".

  • $\begingroup$ Yeah that looks a lot like it. I was just surprised because I didn't hear anything in the radio about it $\endgroup$
    – SirHawrk
    Commented Aug 10, 2022 at 16:07
  • 5
    $\begingroup$ The purpose (if it was today) was most likely to survey one of the forest fires (there were several smaller forest fires in the Karlsruhe region today as well as in the last few days). $\endgroup$
    – dunni
    Commented Aug 10, 2022 at 22:56
  • $\begingroup$ @dunni You are correct. The Police KA stated so on Twitter $\endgroup$
    – SirHawrk
    Commented Aug 11, 2022 at 8:58
  • 1
    $\begingroup$ This is Airbus H-145, previously known as the EC145 (EuroCopter), used a lot by police, ambulance and firefighters, it has an image scanner, follows targets and can install missile systems. It carries up to 8 passengers. It might be confused with the H-135. $\endgroup$
    – user64784
    Commented Aug 11, 2022 at 22:36

Flight tracking sites make use of a technology called ADS-B to track flights. For identification, ADS-B only transmits a 24-bit ICAO address. The site has to look up the address in publicly available databases to find the aircraft that's been assigned that code.

If an aircraft shows up as "blocked", that means the site wasn't able to find the code in its database. That could be for one of several reasons.

  • The plane is new, or it just got a new transponder, and the database hasn't been updated yet.

  • There was a simple network or database error (try reloading the page).

  • The owner/operator of the helicopter has requested that that one specific site not show info on their plane (try other flight tracking sites, like FlightRadar24 or FlightAware).

  • The owner/operator of the helicopter has requested the government to not publish any information about their airplane.

If you have a set of binoculars or something, then you can try to get the registration number off of its tail. If that doesn't work, then I'm afraid your only option is to go down to the airport in question and ask around.

  • 1
    $\begingroup$ One website that censors even less planes than the 2 you mentioned is globe.adsbexchange.com $\endgroup$
    – Ferrybig
    Commented Aug 11, 2022 at 21:07
  • $\begingroup$ Be aware of the privacy initiative from FAA implemented as PIA. Under PIA, the aircraft owner can receive a new anonymous ICAO address every 20 business days. $\endgroup$
    – mins
    Commented Sep 4, 2022 at 16:59

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .