FORT WORTH -- In September, Lockheed Martin production worker Brian Kieffer transferred to Fort Worth from the company's Marietta, Ga., plant to be near his children and grandchildren.
The layoff slip arrived a couple of months later. His last day at the plant in west Fort Worth was Jan. 4.
"They are downsizing," Kieffer said. "Morale is hurt. It's bad."
Life at Lockheed Martin Aeronautics, like at other defense contractors, has had its ups and downs since the plant went operational in 1942, with workers' fortunes often tied to the whims of politicians and generals.
Count the past few months as one of those "down" periods.
Two recent rounds of layoffs, looming cuts in the country's defense budget and a bitter, 10-week strike have created a tense, uncertain atmosphere at one of Fort Worth's largest employers, employees say.
A total of 260 hourly workers have received pink slips since November. The second layoff, announced Monday, was the largest, as 150 workers were told that their last day was expected to be Jan. 25. Lockheed employs about 14,200 people in Fort Worth.
Some veteran employees have taken advantage of a separate voluntary separation program, which provides a lump sum payment to those with 25 years seniority, a union official said. No one would say how many have left under that program.
"There's a lot of anxiety and uncertainty," said Paul Black, president/directing business representative of the International Association of Machinists and Aerospace Workers, Local 776, which represents about 3,600 workers.
That's why dozens have chosen to leave, he said. "That, in and of itself, has contributed to the number of folks who have accepted the separation package."
Lockheed Martin has been under Pentagon pressure to reduce escalating costs on its major fighter jet program, the F-35. Spokesman Ken Ross said that the company intends to keep the factory full of able workers and that the recent layoffs are the result of the "ebb and flow" of normal business practices.
He declined to provide details about the incentive program but said the layoffs were not the result of "sequestration," or automatic spending cuts to defense programs that could result if Congress is unable to reach a budget deal in the coming months.
Lockheed officials have said that its largest program, the F-35, should not have to cut production and jobs immediately, thanks to two recent contracts.
Last month, Lockheed received a Pentagon contract guaranteeing a final installment of about $127.7 million for the fifth production lot of F-35 fighters. Just before year's end, Lockheed and the Pentagon agreed to contracts for a sixth lot of 31 F-35 jets.
About 6,000 of Lockheed's workers at the west-side complex are directly involved in F-35 development, engineering and production, and many other jobs at the plant are tied to the program.
Plans call for Lockheed to build more than 2,400 F-35s for the Air Force, Navy and Marines at a cost now estimated to be $395.7 billion.
But some wonder if that number will ultimately be reduced. Some employees said layoff notices can be issued one week and retracted the next day.
Adding to the uncertainty is the way the aerospace industry must conduct business in an uncertain economy, others say.
"In the past, defense contractors really didn't worry much about the cost because they were able to recover their money," Black said. "Now, it's a different way of doing business, and I understand they have to pinch pennies."
Black and other union employees also said they are trying to recover from the emotional toll of the strike, which ended in July 2012. The new contract established the voluntary buyout program for assembly workers. The buyouts are now being offered to painters at the plant, some employees said.
The offer provides employees $1,000 per year of seniority, not to exceed $30,000.