The Mitsubishi G4M, also known as "Betty," was a Japanese twin-engine bomber used during World War II. Designed by Mitsubishi Heavy Industries, it first flew in 1939 and became operational in 1941. The aircraft was notable for its long range and ability to carry a significant bomb load, making it effective in various roles, including maritime strike missions. The G4M was powered by two Mitsubishi Kasei engines, allowing it to reach speeds of up to 300 mph. Despite its capabilities, the aircraft was vulnerable to enemy fighters due to its lack of defensive armament. It served primarily in the Pacific Theater, where it was involved in numerous missions against Allied forces.