Virgin Atlantic’s US partner Delta Air Lines saw annual net profit rise by $1.1 billion to $2.7 billion last year over 2012.
Profit for the three months to December came in at $558 million.
The improved figures helped the carrier cut net debt to $9.4 billion from $17 billion in 2009.
Chief executive Richard Anderson said: “Our December quarter profit caps off a successful year for Delta with strong profitability and margin expansion, industry-leading operations and significant improvements in customer satisfaction.
“Across the board this was an outstanding year and all credit for these achievements goes to the 78,000 Delta employees worldwide.
“We have a solid set of initiatives in place to improve our financial results, operational performance and customer satisfaction levels beyond 2013’s record levels and remain focused on being the best airline for our employees, customers and shareholders.”
President Ed Bastian added: “With a solid demand environment, industry-wide capacity discipline and a number of Delta’s revenue initiatives already delivering benefits, we expect to produce significant margin expansion in the March quarter.
“As we move through the year, we expect to generate top-line revenue growth as we implement our Virgin Atlantic joint venture, continue to restructure and diversify our Pacific network, gain additional corporate share, and ramp up our merchandising efforts.”