Complete speculation on my part, but maybe the pilot had no intention of attempting to land, but rather just to low fly in a wide open area.
What bolleaux:
If you listen to the guy filming (the passenger) he says 'we've just been told we've got carburettor ice', so it's reasonable to suppose that this was an engine failure followed by a successful crash landing with no injuries.
Note also the complete absence of engine noise in what I take to be a 172, the presence of wind noise and the (muffled but reasonably clear) commentary on a mobile phone camera.
I rest my case.....
Cusco