The application of micro-electro-mechanical systems (MEMS) microphones in the field of aeroacoustics has gained significant attention in recent years. Traditional measurement techniques often struggle with size, weight, and cost limitations, making MEMS microphones an attractive alternative. Nevertheless, the utilization of MEMS microphones for aeroacoustic measurements reveals some challenges to overcome regarding the field of application (i.e. aircraft, wind tunnel), the data acquisition, the calibration and typical implementation problems in general. The following article will briefly summarize the preparation and calibration of MEMS sensors for inflight aeroacoustic measurements as well as two flight testing campaigns performed on DLR aircraft.