Unruly passenger incidents are not only increasing, but also becoming more serious, IATA warns. In 2017, one incident was reported every 1,053 flights, while a year earlier one incidents was reported per 1,424 flights.

In addition to becoming more frequent, incidents are also becoming more serious. In a year to 2017, level 3 and 4 incidents were reported four times more often (4% versus 1% in 2016). Level 3 refers to life threatening behaviors, while level 4 – attempted or actual breach of flight deck security. However, when a drunk passenger falls onto cockpit door, this could also be classified as level 4 incident, Tim Colehan.

One of the issues related to unruly passengers is that a gap in international law often allows the trouble makers to escape prosecution, Tim Colehan, Assitant Director External Affairs of IATA explains. Thus IATA puts hope in Montreal Protocol 2014 (MP14), as it would allow countries to deal with unruly passengers irrespective of where an aircraft is registered. To come into force, it has to be signed by 22 countries – but currently is enforced only by 15. Nevertheless, IATA expects the MP14 to be ratified in 2019.