Pilots from Northwest Airlines and Delta Air Lines are expected to have a blended seniority list by Nov. 20, the Northwest pilots union said in a Wednesday update.

The two pilot groups will have about 30 days -- from Tuesday through Aug. 8 -- to negotiate a seniority list. If they don't reach an accord through bargaining, then unresolved issues will be turned over to three arbitrators.

Northwest and Delta pilots negotiated a four-year deal with Delta management last week that includes annual raises of 4 to 5 percent for both pilot groups. When the merger is consummated, Northwest pilots also would get raises -- an average of 9.5 percent for experienced captains -- to bring them up to Delta levels.

At the time the labor deal was forged, the two pilot groups reached agreement on the process for resolving their seniority differences. A binding seniority list would be issued by Nov. 20.

Typically, pilot seniority conflicts are hashed out over one to three years. But Delta management has pushed for an expedited process and the Northwest and Delta pilot groups want to avoid a protracted pilot conflict like the one that has grown out of the US Airways and America West merger in 2005.

LIZ FEDOR