Gatwick Airport has said demand for air travel might not return to pre-pandemic levels until 2025.
The West Sussex airport announced a 61.3% fall in revenue and a £321 million loss during the first six months of the year compared with the same period in 2019.
Earnings before tax and interest plummeted by 98.3%.
Passenger numbers fell from 22.2 million to 7.5 million over the same period.
The airport said in a statement that the recovery to pre-pandemic traffic levels “is forecast to be four to five years”.
Gatwick Airport announced on Wednesday that it plans to cut around 600 jobs due to the impact of the crisis, representing nearly a quarter of its workforce.
Chief executive Stewart Wingate said: “Like any other international airport, the negative impact of Covid-19 on our passenger numbers and air traffic at the start of the year was dramatic and, although there are small signs of recovery, it is a trend we expect to continue to see.
“However, we are focused on ensuring the business remains robust and is best placed to take advantage of future growth.
“As with any responsible company we have protected our financial resilience by significantly reducing our operational costs and capital expenditure.”
Mr Wingate revealed that despite the collapse in demand for air travel, the airport is pressing ahead with plans to use its emergency runway for routine flights.
It is seeking permission to bring the airstrip into full passenger use.
Gatwick lost out to Heathrow in a bid to obtain Government approval to build an additional runway in October 2016, amid a need for more airport capacity in the South East.
Mr Wingate said: “In this post Covid-19 travelling world, we are working hard with our airlines to ensure we continue to offer our customers a wide choice of destinations and carriers.
“We also expect, next year, to progress our plans to bring the existing northern (stand-by) runway into routine use which, as we rebuild our passenger numbers over the next four to five years, will enable us to offer even more travel choice.
“We will ensure we continue to deliver our operation mindful of our environmental, social and governance responsibilities.
“We want to rebuild better.”