British Airways posted a £208 million ($346 million) loss after tax for the fiscal first half due to a double-digit decline in revenue.
For the six months ending 30 September it had a loss after tax of £208 million compared to a loss after tax of £42 million for the corresponding period last year, BA says to the London stock exchange.
Revenue during the period fell 14% to £4.10 billion from £4.75 billion, it says.
There was an operating loss of £111 million compared to an operating profit of £140 million for the corresponding period, says the Oneworld carrier.
Its pre-tax loss was £292 million compared to a pre-tax profit of £52 million for the corresponding period, it adds.
The group's operating statistics show RPKs fell 1.6% year-on-year and the carrier cut capacity, in terms of ASKs, by 3% which helped to boost the passenger load factor by 1.1 percentage points to 80.6% from 79.5%.
"Aviation remains in recession" but "we were quick to respond to the crisis by taking out excess capacity and, at the same time, driving down unit costs by 5.2%", says BA chief executive Willie Walsh.
"With revenue likely to be £1 billion lower this year, we can't stand still and further cost reduction is essential", he adds.