First prisons upgrade
Drones can be used for useful purposes. But the unmanned flying objects also overcome prison walls. The first prisons are upgrading against them.
For some time now, prison directors have been struggling with a new phenomenon: drone attacks on detention centers have increased worldwide. Germany registers such attempts almost weekly, but Switzerland is also aware of several cases. A flying object loaded with cell phones, drugs and other contraband easily clears the meter-high hurdle. Remotely controlled, it can precisely deposit the goods at a specific location.
No - there has not yet been a specific incident involving a drone at Lenzburg Prison with its almost two hundred places. But those responsible do not want to leave anything to chance. They rely on a high technical and structural safety standard. As a result, they are also among the first prisons in Switzerland to take this new development into account. Drone detection is the magic word.
The arms manufacturer Rheinmetall Defence has been entrusted with the delivery of the system. The Bostadel Intercantonal Prison in Menzingen in the canton of Zug has also ordered such a detection system, according to information from the drone defense supplier. However, Andreas Gigon, prison director at Bostadel, does not want to provide more detailed information. One does not want to inform the inmates and possible helpers indirectly about security measures, Gigon says. The remote prison behind the Menzing hills is a burned child. Unknown persons have already tried to use a drone to get a cell phone into the prison. Of course, this is a better way to organize an escape than without a telephone network to the outside world.
Detection system does not initially work as desired
During an eye inspection in Lenzburg, Christian Harder, deputy head of security, says: "We've already found cut-up tennis balls in the prison yard." The new system is an early warning system. It detects all flying objects, be they drones, model airplanes or balloons. Carrier pigeons are also detected, because they can also play drug mule.
The so-called Radshield system is a reconnaissance system that monitors the airspace above the prison wall with video cameras, infrared sensors and radar. If something is detected, alerts are sent to the prison's operations center. If even small objects of a few centimeters fly over the fence, the "interceptor" triggers an alarm. On the screen, the security staff can finally judge what kind of object it is. But Lenzburg Prison is not yet ready to fine-tune the system, which has been in the test phase since August 2017. At the beginning of November, Christian Harder explained on request that the detection was working at about 80 percent. He is still dissatisfied with the detection of smaller objects.
Headlight poles not stable enough
Another difficulty is posed by the searchlight masts: The multisensors of the drone detection system are mounted on them. The problem is that the metal poles are probably not designed for the additional load, Harder points out. In gusts of wind, they would sway too much, making detection difficult.
In the meantime, the system appears to be fulfilling the prison's specifications. The drone detection system was only recently officially accepted, as Marcel Ruf, director of the Lenzburg correctional facility, announced a few days ago.
Rheinmetall Defence is aware of the difficulty of fine-tuning the system, which can take several weeks. Drones such as a DJI Phantom cause extremely small reflections for the radar. Therefore, the sensitivity must be adjusted so that almost everything is received as a signal by the radar. So also leaves moving in the wind, and of course raindrops. "Rain is one of the big problems, because the mass of raindrops has a reflection ten times greater than the drone," says a Rheinmetall expert.
The Department of Economic Affairs and the Interior in the canton of Aargau is responsible for the acquisition of the 200,000 franc investment for drone detection. According to the canton, the active interference with motorized drones by means of electronic interference mechanisms was deliberately avoided. This is because such a system could not be implemented with the technical development of Drones would not keep pace and would be associated with significantly higher costs, the department argues.
