The Mitsubishi G4M was the main twin-engine, land-based bomber used by the Imperial Japanese Navy Air Service in World War II. The Allies gave the G4M the reporting name of Betty. The Allies usually gave Japanese fighters and floatplanes "male" names, while giving "female" names to bombers and reconnaissance aircraft. These did not come into general use until mid-1943.
The G4M had a range of over 3,700 miles achieved by structural lightness and an almost total disregard for armor protection. This proved to be its weakness when Allied opposition increased in the later stages of World War II.
As a torpedo bomber, the G4M's most notable use was in the sinking of HMS Prince of Wales and HMS Repulse off the coast of Malaya on 10 December 1941. They carried out the attacks alongside the older Japanese bombers, the Mitsubishi G3M "Nells" which were doing high-level bombing runs. The battleship Prince of Wales and battlecruiser Repulse were the first two capital ships ever to be sunk exclusively by air attack during a war, while at sea.
When used for medium to high-altitude bombing against stationary land targets like a supply depots, seaports, or airfields, "ease of interception" was another matter entirely. Using its long range and high speed, the G4M could appear from any direction, and then be gone before many fighters could intercept them. The 20 mm cannon in the tail turret was much heavier armament than commonly installed in bombers, making dead astern attacks very dangerous for the attacking enemy fighters. Sometimes, assuming they did not catch fire in the first place after being hit in the wings by flak from the ground or machine gun bullets from enemy fighter planes, G4Ms also proved to be able to remain airborne despite being badly shot up. For example, after 751 Kokutai's attack during the Battle of Rennell Island, three out of four survivors (of 11 aircraft that went to attack) returned flying on one engine only. Near the end of the war, the "Betty" was used as a common kamikaze-carrying and launching platform, and was the usual aircraft for carrying the Ohka kamikaze rocket aircraft.
General characteristics
- Crew: 7
- Length: 19.97 m (65 ft 6¼ in)
- Wingspan: 24.89 m (81 ft 7¾ in)
- Height: 4.9 m (16 ft 1 in)
- Wing area: 78.13 m² (840.9 ft²)
- Airfoil: Mitsubishi type
- Empty weight: 6,741 kg (14,860 lb)
- Loaded weight: 9,500 kg (20,944 lb)
- Max takeoff weight: 12,860 kg (28,350 lb)
- Powerplant: 2× Mitsubishi MK4A-11 "Kasei" 14 cyls radial engines, 1,141 kW each
- Propellers: 4-bladed Hamilton Standard licensed Sumitomo constant speed variable-pitch
Performance
- Maximum speed: 428 km/h (230 kn, 265 mph)
- Cruise speed: 315 km/h (175 kn, 196 mph)
- Stall speed: 120 km (75 mph)
- Range: 2,852 km
- Service ceiling: 8,500 m (27,890 ft)
- Rate of climb: 550 m/min (1,800 ft/min)
Armament
- 1× 20 mm Type 99 cannon (tail turret),
- 4× 7.7 mm Type 92 machine gun
- 1× 858 kg (1,892 lb) Type 91 Kai-3 aerial torpedo or
- 1× 800 kg (1,764 lb) bomb or 4× 250 kg (551 lb) bombs
** Mitsubishi G4M Betty - Warbird Fare