BOSTON -- Documents obtained Thursday by Team 5 Investigates show how much money the Boston Fire Department is spending to repair and maintain its vehicles.

Boston Fire Department's Truck Repair Spending Doubled | PDF: Truck Repairs | Images Of Crash

Information NewsCenter 5 requested under the Freedom of Information Act shows that in 2006, the department paid $738,659.59 to approximately four dozen repair shops. In 2008, the department spent $1,539,693.05.

The sharp increase in spending for maintenance and repairs is in spite of the fact that Boston's fire department has six full-time firefighters whose sole duty is to maintain and do simple repairs on the city's fleet of trucks and vehicles.

The expired collective bargaining agreement shows that these six staff members generally receive higher, captain or deputy chief's pay.

Other major U.S. cities, including New York, Chicago and Los Angeles, have full-time, in-house mechanics who are responsible for maintenance and repairs.

Team 5 Investigates has previously reported that Boston's fire department also does not schedule routine maintenance for its fleet, something that is considered standard in other cities and recommended as a best practice by national fire safety organizations.

Boston Fire Lt. Kevin Kelley, 52, was killed on Jan. 9 when the ladder truck he was riding barreled down a steep Mission Hill neighborhood street and slammed head-on into an apartment building near the intersection of Huntington and Park Hill avenues in Boston.

A few weeks after the crash, a report in the Boston Globe indicated that faulty brakes were the cause of the collision.