The railroad will begin training about 50 remote-control operators here in August, making this the 15th of the line's regional terminals to change to driverless trains.

Union Pacific spokesman John Bromley said there are no current plans to use remote-control trains outside the switching yard, with the possible exception of servicing clients who are on spur lines within two to three miles of the yard.

Railroads are high on the remote-control technology, similar to that used to pilot drone airplanes in Iraq, because it requires fewer employees and they believe it will prove safer.

The Brotherhood of Locomotive Engineers, however, is fighting the change on the same grounds -- that it will require fewer employees, only they believe it will be less safe.

The dispute could be coming to the City Council soon.

At least 18 cities have adopted resolutions opposing the use of remote-control trains. Democratic City Councilman Jose Ibarra is pressing for Tucson to follow suit, saying he fears once remote-control trains are established in the switchyards it won't be long before they show up on main-line tracks.

A resolution passed by the City Council would not bind the railroad, which is governed by federal transportation and interstate commerce regulations.

With up to 80 percent of trains passing through Tucson carrying some type of hazardous material, Ibarra said he doesn't like the idea of them doing it without a live engineer on board.

"We have no plans to do that at this time," Bromley said.

While piloting a train across the country without an engineer is "not such a big leap" in a technological sense, he said, "politically, it's a huge leap."

Operators will wear belt packs that transmit signals to a computer mounted on the train. The arrangement allows them to run the train from multiple locations onboard or from the ground while walking around the train.

That gives them better visibility of what they're doing and allows the railroad to cut back from two- or three-person crews to one- or two-person crews.

In Tucson, that means the elimination of 18 jobs. Nationwide, Union Pacific expects to cut 600 positions. Bromley said no one will be fired or laid off. Vacancies just won't be filled and employees will be transferred to different positions to accommodate the change.

Because the changeover is just half complete, Bromley said there has been no definitive study to support the belief the new system is safer. But informal observations indicate there appears to have been a 30 percent decline in freight damage at terminals where the new equipment is in use.

But Robert S. Svob Jr., legislative representative for the Brotherhood of Locomotive Engineers, said in some instances a train would begin its shift under remote-control operation, but finished with an engineer at the controls because of an equipment failure. That entire accident-free shift would go in the books as a remote-control shift, he said.