Many passengers were worried about value for money
Complaints from customers about the airline industry have risen by 11% in a year, a consumer support group says.
The Air Transport Users Council (AUC) handled 12,307 complaints and enquiries in 2008-9, compared with 11,077 the previous year.
Cancellations, delays and mishandled baggage topped the gripes list but new technology has also led to new types of complaints, the AUC said.
It accepted that complaints came from a "tiny" minority of passengers.
There were more complaints about cancelled flights than any other issue, with the numbers rising slightly to 3,770 in the last financial year.
The AUC said it had been difficult to win compensation for passengers in these cases because on most occasions airlines claimed cancellations were the result of "extraordinary circumstances", for which they do not have to pay compensation.
The group won compensation for 120 complainants whose flights were cancelled compared with 60 the year before.
Stricter legislation on passenger rights has covered cancellations, delays and baggage handling so the group described the latest figures as "disappointing".
But AUC chairman Tina Tietjen said that changes to the way passengers booked with airlines had brought new challenges.
"The technology that has allowed an increasing number of passengers to book, amend reservations and even check-in online may have brought great benefits to passengers but it has also brought its own problems," she said.
She added that airline charges had also prompted more complaints.
"Many passengers who contacted us were concerned that they were often not getting value for money for the price they were paying for these services," she said.
Separate figures from law firm Hausfeld & Co showed that 211,000 passengers of BA and Virgin have been awarded refunds for fuel surcharges following a class action.
BA was fined for price-fixing on fuel surcharges while Virgin also admitted breaching the law but escaped a fine.
The refunds, to passengers with long-haul airline tickets bought between August 2004 and March 2006, are worth one-third of the fuel surcharge, between about £2 and £10 for each flight.
"Passengers have until December 2012 to claim their refunds," said Hausfeld & Co partner Anthony Maton.