He said Delta's revenue lags competitors' on the same routes, and it still needs to lower its labor costs, shrink its domestic operations and increase its international network.
Aboulafia has a different view.
"Delta and Northwest are the biggest potential," he said, calling a merger between the two carriers a "fantastic" strategy to exit from bankruptcy. "They would be a lot stronger together as they emerged from bankruptcy."
He doubts that Continental, on the other hand, would be interested in buying Delta. "Frankly, I'm not really sure that Continental would want the challenge. They're not all that bad off on their own."
Some experts say there has never been a better time to fix the ailing industry through a few careful matchups.
Delta and its creditors may see a post-bankruptcy link-up with Northwest as a better alternative to the US Airways bid.
The merger plot just thickened at Delta Air Lines. US Airways bumped up its takeover bid for the Atlanta-based airline by 20 percent Wednesday, to $10.3 billion, adding a Feb. 1 deadline in...
The creditors' decision came after an efficient campaign by Delta to torpedo the offer both publicly and behind the scenes.