If you have the same menu entries as before takeoff, this suggests the Couatl engine crashed in flight, using due to bad Navdata. However, the auto-restarter should have restarted it, so the real thing to check is IF the Couatl engine crashed and if yes, why the auto-restarter didn't restart it.
Posting the restarter log located here:
%APPDATA%\Virtuali\Couatl64_boot.log
Might help. Of course, it must be taken from the same session you had that issue.