Promoted to seaman 2d class on December 16, 1938, he was transferred to Patrol Wing (PatWing) 2 in June 1939, and, within the wing, to Patrol Squadron (VP) 21 the following July. He accompanied the squadron as it deployed to the Philippine Islands with its Consolidated PBY Catalina flying boats, and in December 1939 received promotion to seaman 1st class.
Within the next year, he was promoted twice: to aviation machinist’s mate 3d class (May 1940) and aviation machinist's mate 2d class (February 1941). The commencement of hostilities between the United States and Japan in December 1941 found Bangust assigned to VP-101, as VP-21 had been redesignated.
Six PBYs departed their advance base at Ambon in the Netherlands East Indies at 2300 on December 26, 1941 to attack Japanese shipping reported in Jolo harbor in the Sulu Archipelago. Bangust flew as second mechanic and gunner in the Catalina flown by Ensign Elwyn L. Christman, USNR.
“Very accurate” antiaircraft fire from shore emplacements greeted the PBYs as they arrived over the harbor, but it ceased when a group of Mitsubishi A6M2 Type 0 fighters appeared to intercept the attackers. Bangust teamed up with Aviation Machinist’s Mate lst Class Andrew K. Waterman, the other gunner and the plane's first mechanic, in downing the first Zero.
That one attacker having been dealt with, Christman released his bombs in a 60 degree dive, pulled out, and then headed west along the Sulu Archipelago. One fighter followed, attacking the plane’s port side persistently, but Christman sought to foil the attacker by turning into him, forcing him to break off his runs. A deadly duel ensued as the planes headed west; unfortunately, a projectile from one of the Zero’s cannon holed the fuel tank, sending a stream of gasoline into the mechanic’s compartment. On his next run, the Zero managed to ignite the volatile fuel.
Blinded, and having suffered third-degree burns on his face, hands and neck, Bangust joined Radioman 2d Class P. H. Landers, the second radioman, in bailing out of the burning flying boat. Meanwhile, Ensign Christman rode the plane in and landed on the water. Landers, less injured than Bangust, guided the latter’s swimming efforts as they struck out for the island of Lugos. About noon on December 27, Landers glanced behind at his injured shipmate but saw only an empty life jacket--Bangust had apparently slipped from it and drowned. For his “courage and successful machine gunnery” and his “extraordinary heroism” during the action over Jolo, Bangust was awarded the Navy Cross, posthumously.
USS Bangust (DE-739) was named in his honor. The ship was laid down on February 11, 1943 at Los Angeles, California, by the Western Pipe and Steel Co.; launched on June 6, 1943; sponsored by Mrs. Stephen W. Gerber; and commissioned at her builder's yard on October 30, 1943.