ATLANTA — One year into Richard Anderson's tenure at the helm of Delta Air Lines, the company is on the brink of becoming the world's largest carrier through its purchase of Northwest Airlines. But some of the biggest challenges may be yet to come.

Delta and other carriers are flying through a turbulent period in the airline business, including high fuel costs and a weak economy. And Delta still has a number of hurdles to overcome to complete its merger.

Fortunately for Anderson, he isn't entirely new to airline mergers.

As a junior attorney in his first airline-industry job, Anderson was at Continental Airlines when executives pulled off a merger combining Continental with People Express, Frontier Airlines and New York Air in 1987.

"At Continental, I saw it firsthand," Anderson said.

Now, just more that 20 years later, he's overseeing a merger of his own.

Even before he officially stepped into the chief executive position at Delta on Sept. 1, 2007, speculation was rampant that he would move to acquire Northwest, based in Eagan, Minn., where he was chief executive three years earlier. In April, the two carriers announced their deal.

Shareholders are scheduled to finish voting on the deal at shareholder meetings Sept. 25. For the U.S. Justice Department review of the merger, Anderson said Delta has submitted about 10 million pages of documentation and expects a ruling by the end of the year.

Once the two carriers combine, Anderson said, the Atlanta headquarters will be larger, though the company will retain executive offices, reservation centers, a data center and flight-training facility in Minnesota, and some employees from Atlanta may move there. Anderson, a native of Galveston, Texas, comes off as friendly and has a down-home tone, and he often talks about the importance of retaining Delta's culture in the merger. The airline's familylike environment has evolved over decades.

But Anderson's policies and descriptions from some who work closely with him paint a picture of a leader with a different style — one who closely oversees operations, takes more of a no-nonsense approach and isn't afraid to make unpopular decisions.

When Anderson summarizes accomplishments during his first year at Delta, he mentions the announcement of the merger and then ticks off a laundry list of statistics and details on everything from customer service rankings to unit revenues. He has some regrets, saying he wishes Delta had hedged more of its fuel cost and reacted more quickly to adjust to high fuel prices and a weak economy.