After graduating from the PMA, Cabangbang became a fighter pilot for the
Philippine Army Air Corps, the predecessor of the
Philippine Air Force, and was assigned to the 6th Pursuit Squadron led by Captain
Jesus Villamor. Upon the outbreak of the
Pacific War in December 1941 during
World War II, Cabangbang, along with other pilots, lost their aircraft to Japanese bombing raids and were redeployed instead to
Corregidor for land duties. While assigned to the
4th US Marines before agreeing to join the Japanese-sponsored
Bureau of Constabulary. But after completing his training, he escaped to Bohol and joined the
guerrilla movement. In 1943, Cabangbang was recruited by Villamor to work for the
Allied Intelligence Bureau. After serving under Villamor's command in the guerrilla movement in
Negros, Cabangbang was sent to Australia via the submarine
Cabrilla for training. He returned to the Philippines via submarine in July 1944 and was dispatched to the eastern seaboard of
Luzon, where he joined the
Bulacan Military Area guerrilla unit led by Captain
Alejo Santos. Cabangbang was responsible for setting up an extensive network of clandestine radio posts across
Central Luzon which transmitted intelligence reports to General
Douglas MacArthur's headquarters in Australia and enabled Allied forces to
liberate Luzon in 1945. He also helped mediate between Santos' group and the
Hukbalahap that ended fighting between the two guerrilla groups. As a reward, MacArthur named him his direct agent, promoted him to captain and nominated him for the
Distinguished Service Cross. He was eventually awarded the
Legion of Merit. ==Postwar career==