There's definitely been some interest in using amateur HF activity for radar, e.g. https://www.rtl-sdr.com/nils-critiques-the-mh370-wspr-aircraft-scatter-theory

There's definitely been some interest in using amateur HF activity for radar, e.g. https://www.rtl-sdr.com/nils-critiques-the-mh370-wspr-aircraft-scatter-theory/ https://www.rtl-sdr.com/nils-critiques-the-mh370-wspr-aircra...