This time the question is how to fix an outdated air traffic control system, which uses World War II-era ground-based radar instead of satellites for navigation.
Most of the rest of the airline industry wants to address the problem by privatizing air traffic control, largely because the project will cost tens of billions of dollars and is too important to face the continuing delays involved in securing funding from a dysfunctional Congress.
But Delta thinks ATC modernization is moving ahead under the present system and questions the need to change horses in midstream. The complexities of privatization could overwhelm the justification for privatization, the airline argued.
"We are a bit of an outlier as compared to other stakeholders, including most of the other airlines," said Steve Dickson, Delta's senior vice president of flight operations and an Airbus (EADSY) A320 captain. "We think our focus should be to keep our eye on the ball and work with the (Federal Aviation Administration) to improve the current system, rather than getting distracted with separating ATC from the rest of the FAA.
"The work is going on," Dickson said. "The process of separating a huge organization from the government would be a big distraction that would change how we work with the government and set us back."
The debate, which has been going on for a few years, is becoming more pointed as Congressman Bill Shuster (R-Penn.), the chairman of the House Transportation and Infrastructure Committee, works to include ATC privatization in pending legislation to reauthorize the FAA.
But Delta is used to being alone.
Among major U.S. airlines, only Delta operates an oil refinery. Only Delta squares off against every organizing drive in a heavily unionized industry -- a battle it continues to win partially because it has also taken the lead in boosting employee compensation. Only Delta spoke out in favor of President Obama's controversial 2014 move to reshape immigration policy.
Among the big three airlines, only Delta has dramatically boosted capacity in a select market, in its case Seattle, even as it has been a leader in the move toward capacity discipline that has helped shape the industry's maturation.
Also, only Delta would speak out against the Export-Import Bank policy of enabling wealthy foreign carriers to purchase aircraft at a lower cost than U.S. airlines pay. This battle has become problematic because shutting the bank down entirely has become, for some illogical reason, a major cause for Congressional Republicans.
The A4A aviation summit in Washington D.C. last week included a panel on ATC reform. There Sharon Pinkerton, the trade organization's senior vice president for legislative and regulatory policy, declared, "Airlines for America, except for Delta, supports a federally chartered not-for-profit organization.
"It is a momentous change, but it's well worth it," Pinkerton said. "The only way this is going to work is if you have a federally chartered organization outside the federal government."
Delta's Dickson said it is important to remember that the U.S. ATC system is the biggest and most complex ATC system in the world, and yet it is also "more efficient and more cost effective for taxpayers and our customers than any system we have seen."
He said privatization would not address the system's structural issues, including air space configuration and congestion in the Northeast, the key trouble spot.
Improvements are already underway at a score of key airports including Atlanta, where departing aircraft using GPS for satellite navigation can utilize the best flight paths, which allow for continuous descent, rather than the frequent level-offs required in the past. As for arriving aircraft, the system is not quite ready to handle them.
Dickson conceded it will be a slow process to fix ATC, no matter whether it is privatized.
"I would say in technology development, we are maybe 30% or 40% there," he said. "In operational implementation, we are at 5%. We are just starting to have the first things get out there.
"This is a project where we have to keep running the legacy system as we improve," he said. "We are changing the tires on the car as we are going down the road."