The source said ticket sales had leaped 70 percent on Tuesday and Wednesday in comparison to what they would normally have been, without being more specific. SAS spokespeople declined to comment.

SAS on Monday agreed wage cuts, working schedule and pension changes with unions representing cabin crew and pilots as part of a push to reduce costs by 3 billion crowns and secure loans of about 3.5 billion.

"The lid has blown off, people are booking like crazy now," said the source, who declined to be identified. Last week, the same source had said ticket sales had suffered due to the uncertainty over the airline's future and were down 30 percent.

SAS, half owned by the governments of Sweden, Norway and Denmark, has said the deal with unions, along with new loans from banks and governments, will allow it to compete with lower-cost rivals Ryanair (RYA.I) and Norwegian Air Shuttle (NWC.OL).

In the longer term, analysts have said SAS's future depends on it becoming part of a larger airline group.

SAS is due on Thursday to launch a new promotion campaign, offering one million cheap tickets.

"The campaign has been brought forward as they (management) see that confidence has returned. I do not think they will get back all the sales lost last week, but they are well on the way," added the source. (Reporting by Stockholm newsroom staff; Editing by Patrick Lannin and David Holmes)

• A Permanent Economic Emergency