Flybe has reported a half year pre-tax loss of £1.3 million in what it describes as "possibly the most challenging conditions in the last 10 years".
The airline, which achieved a profit of £14.3 million in the same period last year, blamed the drop on falling passenger numbers, high Air Passenger Duty and fuel costs.
Chairman and chief executive Jim French said Flybe was impacted "disproportionately" by high APD compared to its rivals with significant operations outside of the UK.
"We are actively lobbying for some changes in this area although we recognise this will be a long term project," he said.
"The continuing challenges of the UK domestic aviation market further validate the importance of our decision to focus Flybe’s long-term strategy on rebalancing our route network by growing our European operations.
"The UK domestic aviation market continues to show little sign of recovery, with the market trending a year-on-year decline.
"Since this represents 75% of Flybe UK’s passenger base, this decline continues to pose challenges on our UK business."
Looking ahead, French said forward passenger sales revenue for winter 2012/13 at November 6 is ahead by around 2.5% year-on-year.
"Our proactive approach on capacity management means seats flown for the winter period will be about 1% to 2% down against the previous year," he said.
"We are also working on a range of cost saving initiatives over the next 12 months, targeting an annual saving of £2 per seat."