Airline overbooking can be a win-win practice

THE video footage of United Airlines passenger David Dao being forcefully evicted from his plane seat at Chicago O'Hare airport would have sent a chill down many people's spines. Images of the incident have gone viral on social media, sparking outrage around the world and - eventually - an apology from United CEO Oscar Munoz pledging to "fix what's broken".

The incident stemmed from a problem of overbooking on the flight - a common practice in the aviation industry globally where airlines sell more tickets than available seats.

The rationale is that early buyers may not show up for the flight, so selling more than its capacity minimises empty seats and helps the airlines keep their planes as full as possible at the time of takeoff. For passengers, this is supposed to keep prices competitive, while for travellers who have flexibility on their side, overbooking may even be an opportunity for additional cash or voucher compensation, or to be upgraded to a higher class in a later flight.