The airliners of America faced their bleakest hours after the events of September 11, 2001. Millions of dollars were lost in the initial following days when all planes were ordered to remain grounded. Even more money was hemorrhaged in the years afterward. Business deals and vacations were cancelled; people were afraid to fly. Half empty flights went up just as fuel costs started skyrocketing. To keep themselves in businesses, airlines began to consider consolidation, as a way to share costs and keep some measure of profit.

On this day, October 29, in 2008, two of the larger airline companies, Delta and Northwest, both bleeding money, merged in an attempt to keep costs down and their planes flying. The merger created the largest airline company in the world.

Ranked by miles flown by paying passengers, the standard industry metric, Delta alone was the third largest airline, and Northwest the fifth largest. Together, their 200 billion miles flown well eclipsed American Airline’s 133 billion, the largest at the time. Because of the size of the airline, and the $3 billion value of the deal, it got a lot of scrutiny from regulators, but the biggest challenges turned out to come from within, as Delta and Northwest had to figure out ways to merge their previously distinct cultures and business models.