Obi-wan: Fair point. There's perhaps the question of degree of harm they may do to others. And did they continue their experiments and not publish the results on YouTube?? If they continued at an established airfield, their fun would end up being curtailed at some point. What should really worry us indeed is these guys have the ££ to go buy a proper plane, scrape through a PPL and do really stupid stuff....would the "system" spot them, effect their behaviour, change them or would they pass through to become a future AAIB statistic I wonder.....?