<p>Two experimental sounding rockets were launched from And&#248;ya Space Center<br>(Norway) devoted to investigate the phenomenon of polar mesospheric winter<br>echoes (PMWE). PMWE are relatively strong radar returns during winter,<br>observed at various frequencies (e.g. &#8776; 50 MHz Maarsy or &#8776; 224 MHz with<br>EISCAT). Despite possible tracing capabilities for dynamics in the Meso-<br>sphere over a wide annual and altitudinal extend, the formation process is<br>still not understood. To clarify the formation mechanism and proof theories,<br>an experimental setup consisting of two rocket payloads were designed. Aim-<br>ing for measuring neutral air temperature, relative and absolute densities of<br>plasma constituents (electrons, ions, charged aerosols), neutral air and trace<br>gases as well as turbulence. In-situ measurements were complemented by<br>ground based measurements of multiple radars and lidars.<br>We show results from contemporaneous multi instrumental in-situ measure-<br>ments and ground based observations based on the first part of the PMWE-<br>Project and discuss them in the context of most relevant theories.</p>