Type 1, bomber1), g4m21, bettyl3) are G4M naval attack aircraft manufactured by Mitsubishi company of Japan, which are the most famous Japanese bombers in the Pacific War. A medium-sized horizontal / torpedo dual-purpose bomber with dual engines, the Allied code name is "Betty". Its thick and round fuselage is like a big cigar. The early models have no armor to protect its fragile fuel tank, so it is easy to be shot down by the U.S. Army. It is jokingly called "flying lighter". However, with its long range and high speed, the attack plane became a nightmare for the allies at the beginning of the war and served in the Japanese Navy and army throughout the war.