Request to consider Delta, Northwest pilots as one unit may affect union status of others.

Nathan Hurst / The Detroit News

The union representing some 12,000 pilots at Delta Air Lines and Northwest Airlines has submitted paperwork to the National Mediation Board asking the labor authority to consider the two air carriers one entity.

For the pilots, the filing is the last step in a long process of combining Delta and Northwest pilots into one work group as part of a merger of the two carriers; the union is awaiting a decision from arbitrators on the best way to combine their seniority lists.

For the rest of Northwest’s union workers, the board’s decision could be the first step toward the end of union representation. For Delta workers, it could be the first step toward it.

The board’s approval of the pilots’ request — which is subject to review and open to objections from other parties, including the other unions — would set in motion a process to let the carriers’ other workers vote on whether they want union representation.

Once the mediation board rules, the unions would have 14 days to get workers to sign cards supporting a union vote. Only unions that get at least 35 percent of Delta and Northwest workers to sign cards would get to vote.

The flight attendants union already meets the threshold because Northwest attendants, already members, account for more than 35 percent of the combined group.

One union facing trouble, however, is the Aircraft Mechanics Fraternal Association, which represents 900 Northwest workers. Delta, by comparison, has about 7,000 nonunion workers in its technical operations centers.

That means the union would need the support of about 1,800 Delta workers to force a vote.

Delta has long used nonunion labor, but airline officials have said they will let employees decide if they want a union.

Delta submitted documentation to the mediation board in support of the pilots’ filing, which the company says will help resolve issues of representation and seniority between the Delta and Northwest work groups more quickly.

“Delta continues to accelerate processes and decisions that are important to our employees,” Delta spokeswoman Susan Elliott said Tuesday.

Since the merger between Delta and Northwest was announced in April, 26 management work groups at the companies have been working to integrate the two carriers.

Chief among concerns was the integration of more than 22,000 union employees at Northwest and more than 54,000 mostly nonunion Delta workers, with the exception of its pilots and a handful of dispatchers.

Delta acquired Northwest in an all-stock transaction that was approved by federal regulators and finalized last month. Northwest will operate as a subsidiary of Delta until the integration is complete, which is expected within the next two years.

Delta cut a deal with its pilots and Northwest’s before announcing the merger, as an agreement between the two groups would allow a combined company to better realize cost savings from the companies’ marriage. Part of that agreement called for the union to submit the request to unify to the mediation board.

Two of Northwest’s largest unions, the International Association of Machinists and the Association of Flight Attendants, have said they’ll file objections to the filings by the pilots’ union and Delta with the mediation board. They have committed resources to fight for unionization at the merged airline, but say they need more time to organize.

“Each class and craft is in the hunt to win representation,” said Stephen Gordon, president and directing general chairman of District Lodge 143 of the machinists union, in a statement on the organization’s Web site. “Now the commitment must come from within.”

You can reach Nathan Hurst at (313) 222-2293 or nhurst@detnews.com.