You can always go to https://groups.google.com/g/rec.aviation.soaring , click on the top right corner drop down menu, then click on the "Delete" option, if it was really just an inadvertent post, so that it will not be unsuccessfully searched for glider- or soaring related content.

This post was also an accident, right? Same, delete it:
https://groups.google.com/g/rec.avia...m/LuB7sGnlAQAJ