Kusachi Airfield

The airfield was a military installation of the Imperial Japanese Navy. It ceased operations and was officially closed following the surrender of Japan at the end of World War II. The facility was subsequently demilitarized under the Allied occupation.

The former airfield site has been completely redeveloped and is no longer used for aviation. The vast area is now a mixture of:

- **Industrial Zones**: A large portion is occupied by industrial facilities, most notably the Daihatsu Auto Body Co., Ltd. Kyushu Plant.
- **Agricultural Land**: Significant parts of the former runways and grounds have been converted back into farmland.
- **Public Infrastructure**: Roads and other public utilities now crisscross the original site.
- **War Memorial and Historical Ruins**: The site is a designated historical landmark. Several remnants of the airfield are preserved and can be visited. These include sections of the original concrete runway, taxiways, and numerous arched concrete aircraft shelters known as 'entaigō' (掩体壕). A dedicated museum, the Usa City Peace Museum (宇佐市平和資料館), has been built on the grounds to preserve the history of the airfield, honor those who died, and serve as a center for peace education.

The facility known as Kusachi Airfield (a local name for one of its areas) was historically the Usa Naval Airfield (宇佐海軍航空隊 - Usa Kaigun Kōkūtai), a major base for the Imperial Japanese Navy Air Service (IJNAS) during World War II. Its significance is profound:

1. **Primary Training Center**: It was one of the largest and most important training centers for carrier-based aircraft pilots in Japan, specializing in the training of crews for dive bombers (like the Aichi D3A 'Val') and torpedo bombers (like the Nakajima B5N 'Kate').

2. **Kamikaze Staging Base**: In the final year of the war, Usa Airfield became a crucial forward base for 'Special Attack' (tokkōtai) or kamikaze missions. A large number of pilots and aircraft departed from Usa on one-way missions, primarily targeting the US fleet during the Battle of Okinawa.

3. **Allied Target**: Due to its strategic importance, the airfield was heavily targeted by Allied bombing raids, particularly by American B-29 bombers in the spring and summer of 1945, which caused significant damage to its facilities.

There are zero plans or prospects for reopening the airfield. The land has been irrevocably repurposed for industrial, agricultural, and memorial use. The extensive construction, division of land ownership, and its status as a historical war memorial make any future aviation use completely infeasible. The nearby Oita Airport (RJFO) serves the region's current aviation needs.