A system to detect a pressure difference between the interior of a cabin of an aircraft and the exterior of the aircraft. The system includes a window arrangement having a first windowpane with a first surface and an opposite second surface and is adapted to be mounted in an aircraft such that the first surface of the first windowpane faces the exterior of the aircraft and is subjected to ambient outside atmospheric pressure and the second surface faces the cabin interior, and a pressure sensor including a first pressure port. The first windowpane includes a first air passage opening extending between the first and second surfaces of the first windowpane, and the pressure sensor is sealingly connected to the first air passage opening such that the first pressure port of the pressure sensor is subjected to pressure acting on the first surface of the first windowpane.