Since 1974, some U.S. Air Force air transport units have been trained and equipped to help fight forest and brush fires. While these fires are sometimes a problem for military bases, or even in a combat zone, the main purpose of this air force program is to provide assistance to local governments in fighting such fires. Providing this kind of disaster relief is a frequent, and much appreciated, chore for active duty and reserve units. The Air National Guard and Reserve C-130s are using MAFFS (Modular Airborne Firefighting System), which is a system you just slide into the cargo bay of a C-130 and show the crew how to use it. A MAFFS unit carries 2,700 gallons of pressurized slurry fire retardant (a biodegradable mix that works better at slowing fire down than plain water). Flying as low as 100 and nearly at stall speed, the C-130 covers an area with fire retardant that is 1,500 feet by 100 feet. This takes six to eleven seconds. The C-130 then lands, reloads, and does another sortie. The air force currently has eight MAFFS units and they fly an average of 240 sorties a year.