Manassas-based Colgan Air Inc. has been hired by United Airlines to begin flights to six small cities, continuing the local carrier's expansion.

Chicago-based United is the third major carrier to use Colgan for regional flights. The airline will fly routes for United between Dulles International Airport and six small airports using its fleet of Saab 340B turboprops, a 34-passenger aircraft.

On Oct. 4, the airline will begin flying daily routes to Charlottesville; Charleston, W.Va.; Allentown, Pa.; Binghamton, N.Y.; State College, Pa.; and White Plains, N.Y., under the United Express name.

Fort Wayne, Ind.-based Shuttle America Corp. had operated those routes, flying a 30-passenger turboprop fleet for United. But Colgan offered United, which is in Chapter 11 bankruptcy protection, a larger aircraft at a lower rate.

"We're able to increase the number of passengers on these routes as well as get better economics on our agreement for these particular routes," said Jeff Green, a United spokesman.

Shuttle America will continue to operate 70-seat regional jets for United Express out of Dulles.

Major airlines make deals with regional carriers to fly passengers from small airports to their hubs instead of sending their larger aircraft to smaller markets.

For Colgan, the new partnership means the airline will add 100 pilot and flight attendant positions. Half of those employees will work out of Manassas.

The airline has added 300 jobs since March when it began flying routes for Houston-based Continental Airlines Inc. Under the Continental Connection name, Colgan operates flights between Houston and cities in Texas, Arkansas and Louisiana.

Since 1999, the carrier has flown routes for Arlington-based US Airways Group Inc., serving 10 states on the East Coast under the US Airways Express name.

Colgan's expansion plans include building a new 40,000-square-foot facility inside the Innovation@Prince William industrial park and relocating its headquarters from the Manassas Regional Airport.

In June, Colgan purchased 10 acres of land from the county for $1.7 million and plans to spend another $1.7 million constructing new offices and a training facility. The building should be complete by March 2007, and about 250 employees will work there.

Colgan Air Inc. already flies commuter routes for Continental Airlines and US Airways Group.