Northwest Airlines is losing more than $3 million a day, has filed for bankruptcy, and says it needs to cut its payroll costs by $1.4 billion a year. The airline and its major unions have been negotiating over concessions. A U.S. Bankruptcy Judge has given the company and union negotiators until Wednesday to reach a settlement. If there is no agreement the Judge has the power to terminate the union contracts — a decision both unions say would prompt a strike. Michigan Radio’s Jack Lessenberry spoke with Peter Rachleff -- a professor of labor history at Macalester College in St. Paul Minnesota.