Lockheed Martin has turned up the pressure on striking Machinists union members, announcing it would begin hiring temporary replacement workers to fill aircraft production jobs.
A handful of workers were being brought in from a temporary employment service and a few dozen more would be added next week, Lockheed spokesman Joe Stout said on Thursday.
"We will add people incrementally each week as we need to," Stout said, with the goal of improving and boosting production until the Machinists return to work.
The action by Lockheed to begin augmenting its production workforce comes as the strike by about 3,600 members of the International Association of Machinists & Aerospace Workers is in its fifth week.
The aerospace industry historically has large numbers of skilled and experienced workers - job shoppers, as they're known - employed through temporary agencies that companies can utilize for varying periods of time.
Robert Wood, a spokesman for the Machinists union, downplayed the move by Lockheed, saying it would not significantly weaken the resolve of striking members to hold out for a better contract than the one overwhelmingly rejected on April 22.
"What they're trying to do is get a whole bunch of people to cross the line on Tuesday" after the Memorial Day holiday, Wood said.
Rank-and-file support for the strike remains strong, Wood said, with relatively few having crossed the picket line to return to work.
The strike is close to becoming the longest in the history of the west Fort Worth aircraft plant.
There was a six-week strike in 1946 against Convair, the plant's operator. A walkout in 1984 against General Dynamics lasted three weeks, and the union struck against Lockheed for two weeks each in 2000 and 2003.
Union members voted down a Lockheed contract offer that called for three per cent annual pay raises over three years and a $US3,000 ($A3,086.26) signing bonus, plus a 13 per cent increase in future pension benefits.
The union baulked primarily at Lockheed proposals to limit employee health benefit program choices and to eliminate a traditional pension plan for new hires.
In a memo Thursday announcing the hiring of temporary workers, Lockheed Executive Vice President Larry Lawson said the company made a fair and generous offer to the IAM members, but we have a fundamental disagreement on retirement savings.
"The transition to a defined contribution pension plan for new hires is an industry standard, which we have successfully implemented in a number of recent labour agreements, and is a necessary action that will help us deliver greater affordability to our customers."
As the Pentagon's budgets shrink, the military services and defence contractors are under pressure to hold down or even reduce costs.
Lockheed is the prime contractor on the F-35 Joint Strike Fighter, the largest and most expensive weapons program ever, which is years behind schedule and badly over budget and has been a ripe target for criticism.
The union, in a blog post on its website, challenged Lockheed's cost-benefit calculations on bringing in temporary workers.
"It's surprising how Lockheed Martin demands to slash our health care and go after our pension plans to 'save money for the customer,' but they can waste all kinds of money during this strike," the union stated.
Lockheed claims it has been able to maintain some level of production and, in some cases, even improve efficiency during the strike by assigning some 1,700 salaried workers - many of them with previous experience - to production and testing jobs normally filled by the union members.
Keep reading - next article