Defensive Guerrilla Tactics
Defensive tactics included attrition operations such as anti-air combat, permanent and temporary minefields, sniper attacks, ambushes with mines and with small arms, and harassment with ramps and mortars. In addition, the FMLN considered patrols and searches, false camps, and the evasion maneuver as defensive tactics. The FMLN did not use defensive tactics to defend a static position; rather, defensive tactics were used to wear down and delay army units on the offensive. Terrain was defended not by holding it, but by inflicting heavy enough casualties on the enemy force that it could or would no longer continue to advance. If an enemy advance could not be contained, defensive tactics were used to delay advancing army units to allow FMLN combat forces and masses to evacuate the area.
The FMLN felt that the primary advantage of the armed forces vis-à-vis the guerrillas was its possession and use of airpower. While in the early part of the war the Salvadoran air force was small and generally antiquated, the military developed ingenious methods to keep its air force flying, and equally ingenious tactics to give the armed forces the edge in any battle. When the military began receiving U.S. aid, one of its first priorities was to increase the size and power of the air force to give it a greater tactical edge over the insurgents. Maintaining this tactical edge remained one of the top priorities for the armed forces throughout the war. By the end of the conflict, the Salvadoran military possessed a formidable fleet of UH-1 and Hughes 500 transport, reconnaissance, and