Picket lines went up early Saturday at Boeing airplane factories. More than 27,000 machinists are on strike after last-minute contract talks collapsed.

Boeing could lose as much as $120 million a day in lost revenue according to industry analysts. That’s mostly from revenue that will be deferred when those commercial jets that Roberts and Arias help make won’t be built or delivered because of the work stoppage. The jet-making factories in Renton and Everett will remain open, but there are no mechanics to do the work.

Perhaps worse for Boeing, the 787 Dreamliner, already some 14 months behind schedule because of production issues, may not fly for the first time until 2009 because of the strike. Customers have ordered 900 of the fuel-efficient planes, but deliveries have already fallen as much as two years behind schedule in some cases. A long strike could cause further delays and upset customers even more.

Boeing began shutting down its jet production lines at midnight, when the strike began.

Picket lines went up early Saturday at Boeing airplane factories. More than 27,000 machinists are on strike after last-minute contract talks collapsed.