Top leaders at the International Association of Machinists and Aerospace Workers overruled its Puget Sound branch, District 751, and ordered that it allow its members to vote early next month on the latest proposed contract from the Boeing Co., where most of its members work. The local leadership has nevertheless called its members to reject the contract.

The split is the latest twist in several months of turmoil between the aerospace company, District 751's officers and the union's rank and file over the union's contract and whether the company will stay in the area.

The move suggests that IAM's leadership is concerned that District 751 is mishandling the situation. District 751 President Tom Wroblewski has reportedly demanded a written explanation from IAM President Tom Buffenbarger, according to a report Saturday by the Everett (Wash.) Daily Herald.

On Nov. 13, rank-and-file members voted down a proposed contract with Boeing that would have included a modest raise, a $10,000-per-person signing bonus and the conversion of the defined benefit pension into a 401(k) system, among other changes. This was despite the fact the proposal had been worked out with in negotiations with District 751 officials. The members were reportedly upset over the pension change.

Boeing has said that the changes were necessary for the long-term viability of the plant. It has warned it may move production if a contract isn't reached. It has already made preliminary steps to do so.

Last week, District 751 rejected out of hand the latest offer by Boeing, calling it no better than the one members rejected the month before. Some rank-and-file members were upset over the decision, saying they should get a chance to vote. One member even filed a complaint earlier this month against District 751 with the National Labor Relations Board over the matter. Opinion within the union is hardly uniform, though.