Measuring arrangement for detecting a 1/rotary momentum of an engine rotor, and associated method

A measurement system for detecting a rotary movement of a rotor that is situated in rotatable fashion in a compressor housing of a jet engine, comprising:

• the rotor having a plurality of overlapping vane elements at least one distance sensor is provided and is configured for measuring a distance between each of said vane elements and said distance sensor and generating a corresponding distance measurement signal, and at least one material measure being fashioned on the rotor that can be periodically detected by the distance sensor due to the rotational movement of the rotor, the at least one material measure is formed by at least one modified vane element that is truncated in the area of the vane tip, the distance sensor outputting an identical distance measurement signal in each case when the vane elements travel past, and outputting a modified distance measurement signal when the modified vane element travels past the distance sensor.