New to Flightgear 2017.2.1 but not to flight sims. Trying the MacOS X version with Cessna 172p on active runway of KFSO at noon. At startup, before powering up, plane bangs around as if in a tornado, finally comes to rest upside down. On tutorial of Preflight checkout, same happens with terrible wind sound between voice snippets.
Weather is clear, wind at 3 knots or less, clear at center of high pressure area. Other settings are for quiet, normal flying. Mac OS X El Capitan on an iMac machine, no other software problems noticed. Anyone seen this happen before?