Seattle ? The Boeing Co., which cut its Washington state work force by 27,000 after the 9-11 terrorist attacks, has been quietly adding personnel in its Puget Sound operations.

The Chicago-based aerospace giant now has 55,209 workers in Washington, 1,676 more than at the start of the year, according to employment numbers posted on the company Web site Dec. 2.

The local work force grew by 497 jobs during the past month and has had a net gain every month for the past six months. The low point was 52,763 workers reported June 3.

Boeing said in July that it expected to add 2,000 to 3,000 jobs by the end of the year, “and we’re right on track with that,” spokesman Chris Villiers said.

The hires so far are roughly split between machinist jobs and engineering and technical positions, he said.

Boeing had 80,000 workers in Washington on Sept. 6, 2001. One week after the Sept. 11, 2001, terrorist attacks, the company announced plans to lay off as much as 30 percent of its Commercial Airplanes workers.

Boeing moved its headquarters from Seattle to Chicago in September 2001. Worldwide, it employed 199,000 people just before the attacks.

On Jan. 2 of this year, Boeing employed 157,518 workers worldwide. It now has 159,444, up 1,926. All but 250 of those new jobs are in the Puget Sound area.

In Wichita, Kan., where Boeing is that state’s largest employer, workers are waiting on word of a possible sale of Boeing Commercial Airplanes’ Wichita division.

A sale would include Boeing’s plants in Tulsa and McAlester, Okla. Boeing Wichita’s military facility is not up for sale.

Speculation on possible buyers has centered on Toronto investment firm Onex Corp., Washington D.C.-based Carlyle Group and Dallas-based Vought Aerospace, which is owned by Carlyle Group.