Demand for passenger airline service in Rutland is strong enough that Cape Air has added a fourth daily flight to Boston.
State airport division chief Guy Rouelle says business on the Boston route has increased 21 percent since it started in 2007.
"And we’re looking at a 25 percent increase this year in emplanements, in passengers," he said.
Passenger service has been offered at the Rutland-Southwest State Airport for many years with a subsidy from the federal government.
That’s still true, but the new flight to Boston has been added without a subsidy.
Officials say more than 11,600 passengers flew in and out of the airport in 2011, which was a record in Rutland.
The Rutland airport is one of only two in the state with scheduled passenger service. Burlington is the other.