Could someone explain to me how to engage HDG mode, so that it actually works? When I tried, it stayed on course for a bit, then went into a stall and crashed. (The AP was engaged, along with HDG mode.)
HDG mode only controls lateral direction, not altitude or attitude. So if you have HDG mode engaged but not ALT mode and your aircraft is not trimmed properly you can definitely get into a nose high attitude with a loss of airspeed leading to a stall.