Airplane tracking websites Flightradar24 and PlaneFinder were hacked in a number of cyberattacks.
The incidents prevented users from accessing feeds following the “ongoing attacks” on websites monitoring traffic in the UK, airports like Birmingham, Heathrow, Manchester, Cardiff and beyond.
Flightradar24 stated that it suffered three attacks within two days and initially had difficulty in getting service back on track.
PlaneFinder said: “At the moment there may be problems accessing PlaneFinder. It seems it is our turn to attack our systems. Our team is working hard to get service back to normal. Please contact us, we will Provide updates as soon as we have them. “
Both websites allow users to follow the flight paths of commercial and private aircraft around the world. Some military services are also followed.
Flightradar24 lists approximately two million users and tracks 180,000 flights daily. Customers include aircraft manufacturers such as Airbus and Boeing.
The location can identify an aircraft model, flight number, and distress signal codes. It was reported to be back in service on Tuesday, but users are still complaining about various charging issues.
Many aircraft spotters use the service for free, however there is a more detailed option that can be accessed with a subscription.
There have been online claims that the cyber attacks were carried out by various foreign government agencies implicated in the conflict between Armenia and Azerbaijan.