Betty Bomber - Chuuk (Truk) Lagoon

We love the Betty Bomber for its sheer completeness. It’s a Type 97, Mitsubishi G4M, and she sits upright on a sandy bottom, surprisingly shallow given the history. We usually find her at around 15 metres, depending on the tide, making her an easy, long dive. The cockpit is a highlight, clear to see with the instrument panel still somewhat intact, and the machine guns are still mounted in the tail section. It’s a tangible link to Operation Hailstone. Look closely, and you’ll see soft corals already starting to encrust the fuselage, with schools of glassfish shimmering around the wings. It’s a moving experience, perfect for wreck enthusiasts who appreciate history and the slow reclamation by the ocean.

Location
Chuuk (Truk) Lagoon, Micronesia, Central & South Pacific
Coordinates
7.350750, 151.878860
Type
wreck

Wreck History - Betty Bomber

Year Sunk
1944
Vessel Type
aircraft
Cause
combat

One of the most iconic aircraft of the Pacific War, the Mitsubishi G4M was a fast, long-range bomber given the Allied codename 'Betty.' Japanese pilots nicknamed it 'Hamaki' (cigar) due to its cylindrical shape. This shape, combined with its lack of armor or self-sealing fuel tanks, also made it notoriously vulnerable to enemy fire, earning it the less flattering nickname 'the flying lighter' from Allied pilots.

Lying in the calm, clear waters of Chuuk Lagoon, this particular Betty Bomber is a casualty of the massive American air raid, Operation Hailstone, in February 1944. The aircraft is remarkably intact, resting upright on the seabed. Divers can clearly see its distinctive twin engines, long fuselage, and cockpit, now encrusted with corals and home to a variety of reef fish. It is a poignant and beautifully preserved piece of World War II history, offering an unforgettable glimpse into the past.

Best Time to Dive in Chuuk (Truk) Lagoon

The warmest water temperatures in Chuuk (Truk) Lagoon occur in January, averaging 28.9°C. The coolest conditions are in December at 28.9°C.

Monthly Water Temperatures

  • January: 28.9°C (air: 27.8°C)
  • February: 28.9°C (air: 27.7°C)
  • March: 28.9°C (air: 27.5°C)
  • April: 28.9°C (air: 27.5°C)
  • May: 28.9°C (air: 27.7°C)
  • June: 28.9°C (air: 27.5°C)
  • July: 28.9°C (air: 27.5°C)
  • August: 28.9°C (air: 27.7°C)
  • September: 28.9°C (air: 27.7°C)
  • October: 28.9°C (air: 27.9°C)
  • November: 28.9°C (air: 27.9°C)
  • December: 28.9°C (air: 27.9°C)

Nearby Dive Sites in Chuuk (Truk) Lagoon

Nearest Dive Centres to Betty Bomber

Marine Life in Chuuk (Truk) Lagoon

Home to 213 recorded species including 133 reef fish, 36 hard corals, 17 sea cucumbers, 12 sea snails & nudibranchs, 5 sharks & rays, 4 clams & mussels.

Notable Species

Recommended Packing List for Betty Bomber

Based on average water temperature of 28.9°C.

  • Shorty or Rashguard - warm 29°C water needs minimal exposure protection
  • Mask - essential for every dive
  • Fins
  • BCD - buoyancy compensator
  • Regulator - your most safety-critical piece of gear
  • Dive Computer - tracks depth, time, and NDL
  • Surface Marker Buoy (SMB) - essential for boat pickups
  • Dive Torch - useful for crevices and colour at depth
  • Underwater Camera - capture your diving memories