FORT WORTH -- About 110 workers, mostly aircraft assemblers, were laid off at Lockheed Martin Aeronautics in west Fort Worth on Friday as a result of budgetary pressures in the defense industry, officials said.Employees received notice of the layoffs in November, Lockheed spokesman Ken Ross said Wednesday."The big thing is that we're going through a changing environment,"' he said. "We're responding to what is happening in the industry ... we want to make sure we remain competitive."Ross said the layoffs are not related to sequestration, the looming budget cuts that are possible if Congress cannot work out a budget deal in the next two months.Ross said he could not speculate about more layoffs, which he said are part of the "ebb and flow" of workers in the plant."Our intent is to keep the factory as full as possible ... but we can't speculate as to what's happening in the future," he said.Lockheed employs about 14,200 workers at the west-side complex which makes F-16 and F-35 fighter jets.