MAREA, Syria – Lt. Col. Maan al-Mansour’s mission is to capture the Syrian air base where he once served.

The 22-year air force veteran, who defected in June to the rebellion, led an attack by hundreds of fighters on the Kuwiras military airport last week. In a fierce battle, they hammered the base with mortar fire and rocket-propelled grenades for four hours, nearly overrunning it until they were driven back by sustained strafing and bombing by jet fighters.

Al-Mansour says he’s determined to try again. Syria’s rebels have turned to a new tactic of attacking bases, trying to stop the jets and attack helicopters that have wreaked devastation on their fighters and civilians in the battleground city of Aleppo and the nearby countryside.