When passengers are bumped off overbooked flights, the practice in Singapore is to ply them with compensation. This includes travel vouchers, meals or hotel accommodation, on top of being placed on an alternative flight to the destination, airlines told The Straits Times.

There have been zero complaints against overbooking from January last year to date, said a spokesman for the Consumers Association of Singapore. Said Singapore Management University's transport specialist Terence Fan: "Customers who are bumped off are typically well- handled and well-compensated here. The staff might tell you they could upgrade your ticket to business or first class for your next flight, for example."

The issue of what airlines do when flights are overbooked is now a talking point, after a United Airlines passenger was dragged from an overbooked plane on Sunday. Aviation analyst Shukor Yusof of Endau Analytics said overbooking is not illegal, but United handled the situation poorly: "There are many other ways to persuade passengers to not fly, apart from using brute force."

A Jetstar spokesman said: "Airlines in this part of the world have a much more conservative approach to overbooking than airlines in the United States."

In Singapore, he said the passenger will be bumped off and placed on an alternative flight at the check-in counter, rather than be made to deplane after boarding.

The management of these passengers is "carefully handled" by Singapore Airlines, said its spokesman. "We are generally able to accommodate or make alternative arrangements for our customers who have a confirmed booking."

It is an industry practice for airlines to overbook, as almost every flight has a small percentage of passengers who do not show up, said a spokesman for Scoot and Tigerair. Affected passengers can get a full cash refund if they prefer to make their own arrangements, he said.

The airlines did not respond to questions on how often they need to bump off customers, and how they decide who must give up their seats.

Professor Fan said the practice is necessary as airline companies operate on razor-thin margins. "It allows airlines to compensate for no-shows from other passengers. These passengers might pay a cancellation fee, but it will not completely recover the cost of having empty seats on the flight," he said.