Abstract: The sensor device serves for detecting the absence or presence of a liquid (1) at the outlet (10a) of a feed line (10) through which there can be fed a feed substance which, when exiting from the outlet, has a pressure (p) in the feed line which has a course over time with a first characteristic in the absence of the liquid and has a course over time with a second characteristic in the presence of the liquid. The sensor device includes a sensing instrument (20-23) for sensing the pressure fluctuations in the feed line (10) and evaluator (30) which is designed to assign the sensed pressure fluctuations to the first or second characteristic and to generate a corresponding signal which indicates whether the liquid (1) is absent or present at the feed line outlet (10a).

Abstract: The sensor device serves for detecting the absence or presence of a liquid (1) at the outlet (10a) of a feed line (10) through which there can be fed a feed substance which, when exiting from the outlet, has a pressure (p) in the feed line which has a course over time with a first characteristic in the absence of the liquid and has a course over time with a second characteristic in the presence of the liquid. The sensor device includes a sensing instrument (20-23) for sensing the pressure fluctuations in the feed line (10) and evaluator (30) which is designed to assign the sensed pressure fluctuations to the first or second characteristic and to generate a corresponding signal which indicates whether the liquid (1) is absent or present at the feed line outlet (10a).

Abstract: A take-off device includes a telescopic arrangement of three pipes arranged in a frame. The telescopic arrangement can pivot to a limited extent. The frame is mounted on a horizontal axis running through a center of gravity of the device and a centroidal axis of a lift of an airplane wing, whereby the frame can pivot around the axis. Forces exerted between the telescopic arrangement and the frame are transmitted via a bushing wedged on an outer pipe of the three pipes. A compressed gas accumulator can be opened by means of an actuating pressure signal, whereupon the telescopic arrangement extends outward. A bottom portion of an innermost tube knocks against a fixed point on the ground, which allows the airplane to accelerate to a lift-off speed. After the telescopic arrangement has extended outward, the telescopic arrangement retracts inward using a compressed gas stored in a pressure chamber.