From the Living Rule Book:
(p24) Cavalry and monsters can’t move into or over terrain features on the battlefield except for hills, bridges, shallow fordable rivers and low obstacles (hedges, walls, fences or ditches, for example).
... I would say NO.
(p85) The Gyrocopter is a flying machine, so all the usual flying rules apply (see Flying Units p.59-61).
.... So, NO, unless there is a designated area e.g. the market square (agreed b/w players) that is "open" and the gyrocopter can land there.