Delta Air Lines has posted a $3.9 billion adjusted pre-tax loss for the second quarter of 2020 as it predicted it would take more than two years to mount a sustainable recovery.

The adjusted pre-tax loss marked a $5.9 billion swing from the same quarter in 2019, when the airline posted a $2 billion profit.

Revenue plummeted from $12.5 billion to $1.2 billion, illustrating the “truly staggering” impact of the Covid-19 pandemic.

Ed Bastian, chief executive, said: “A $3.9 billion adjusted pre-tax loss for the June quarter on a more than $11 billion decline in revenue over last year, illustrates the truly staggering impact of the Covid-19 pandemic on our business.

“In the face of this challenge, our people have acted quickly and decisively to protect our customers and our company, reducing our average daily cash burn by more than 70% since late March to $27 million in the month of June.”

Bastian added: “Given the combined effects of the pandemic and associated financial impact on the global economy, we continue to believe that it will be more than two years before we see a sustainable recovery.

“In this difficult environment, the strengths that are core to Delta’s business – our people, our brand, our network and our operational reliability – guide every decision we make, differentiating Delta with our customers and positioning us to succeed when demand returns.”

Delta said it had bolstered liquidity to $15.7 billion at the end of June through new financing and government funding during the quarter, with adjusted net debt of $13.9 billion increasing by $3.4 billion since the beginning of the year.

The Atlanta-based airline planned to add 1,000 flights a day in August but said it will now add half that number due to ongoing suppressed domestic demand.