The measures taken range from outsourcing of calls to getting on Facebook.

Complaints received by the Consumers Association of Singapore (Case) include unexplained delays and cancellations and loss of baggage.

Other grouses: inability to contact the airlines; hidden costs; delayed refunds; and cancellation fees for flights cancelled by the airlines.

Last year, Case received 157 complaints against budget airlines. There were 75 such cases in 2007 and 78 in 2006.

Tiger Airways topped the list with 55 complaints till date this year, followed by Jetstar Asia Airways with 36 cases. Malaysian budget carrier AirAsia had 14 cases.

Mr Seah Seng Choon, executive director of Case, said the spike in complaints could be due to more passengers switching to budget carriers in the downturn.

Budget airlines The Sunday Times spoke to, agreeing there has been a sharp spike in demand, said they are trying to cope with the volume.

This relatively new industry is also learning the ropes.

Read the full story in tomorrow's edition of The Sunday Times.