Tanzania's active armed forces totaled 27,000 in 2002, with reserves numbering 80,000. The army had 23,000 personnel in five infantry brigades, one tank brigade, and one engineering regiment. Equipment included 45 main battle tanks and 55 light tanks. The navy had 1,000 personnel and six patrol and coastal combatants. The air defense command numbered 3,000 operating 19 combat aircraft. Police field forces, which include naval and air units, numbered 1,400. Tanzania participated in two peacekeeping efforts on the continent. Defense spending was $19 million in 2001, or 0.2% of GDP.