Student drivers have replaced hired professionals for the Harvard-Radcliffe shuttle bus service.

The program began with the hiring of 15 students this week, Thomas Vacha, Central Services manager, said yesterday. The students became eligible for the job after passing a two-week driver's training course.

Vacha said last year's drivers were hired from a contracting company in Ashland. The company was unwilling to supply drivers when campus groups asked to use the buses for charters or short trips.

Under student operation, the buses will now be available for charter service, Vacha said. Another improvement over last year's system, he said, is that money spent paying drivers will now be helping students on financial aid.

Fifteen more students will be hired later this month Vacha said yesterday. They will work 15 hours a week at $3.50 an hour.

The students are driving newly-purchased, crimson-and-gray buses. The route is basically the same as last year's, covering the Quad Houses and the Business School. The buses run from 4 p.m. to 1 a.m. daily.

The shuttle bus service began last year in an attempt to protect students from rising crime in Cambridge. The program will cost Harvard about $35,000, the same as last year.