Kakamigahara Airfield (Gifu Air Base)

Kakamigahara Airfield, located in Kakamigahara City, Gifu Prefecture, is one of Japan's oldest continuously operating military airfields and a site of exceptional significance in Japanese aviation history. The field's origins trace to 1917, when the Imperial Japanese Army converted former 3rd Division artillery maneuver grounds into an airstrip — making it the second military airfield built in Japan after Tokorozawa.

In 1918, the Army's 2nd Aviation Battalion relocated here from Tokorozawa, establishing Kakamigahara as a major military aviation center. The favorable westerly winds from nearby Mount Ibuki provided excellent conditions for takeoff and flight testing. By the 1920s, Kawasaki Dockyard Company (later Kawasaki Aircraft Industries) established a manufacturing plant adjacent to the airfield in 1923, creating an integrated complex for aircraft production and testing.

The airfield's most historically significant moment came on April 1, 1939, when chief test pilot Katsuzo Shima conducted the maiden flight of the Mitsubishi A6M1 — the prototype that would evolve into the legendary Zero fighter (零式艦上戦闘機). The prototype had been disassembled and transported by road approximately 36 kilometers from the Mitsubishi Aircraft Company factory in Nagoya. After taxi tests and a brief hop to check control response, Shima took off at 5:30 PM on a successful test flight that launched one of the most famous fighter aircraft in aviation history. Since 1917, a total of 74 aircraft types have made their maiden flights at Kakamigahara — more than any other airfield in Japan.

During World War II, the Kawasaki factory adjacent to the airfield became one of Japan's most important aircraft production facilities. The plant mass-produced the Ki-61 Hien (飛燕, "Flying Swallow"), the Imperial Japanese Army's only mass-produced inline-engine fighter. Production reached a peak rate of 200 aircraft per month, with a total of 3,285 Ki-61 and its successor Ki-100 fighters built at the facility. The airfield also served as a flight testing and delivery center for these aircraft.

In the final months of the war, Kakamigahara became a target of American strategic bombing. On June 22, 1945, B-29 Superfortresses struck the Kawasaki aircraft factory and airfield installations as part of a coordinated attack on six industrial targets across southern Honshu involving 382 bombers. The raids inflicted devastating damage on the Kawasaki Gifu Works, effectively destroying the factory's production capacity.

Following Japan's surrender, the airfield was requisitioned by the United States military and designated Camp Gifu, serving as a US military installation until its return in 1958. Control was transferred to the Japan Air Self-Defense Force (JASDF), and the facility was redesignated JASDF Gifu Air Base (ICAO: RJNG). Today it serves as home to the Air Development and Test Wing, responsible for testing and evaluating new aircraft and weapons systems for the JASDF.

The Gifu-Kakamigahara Air and Space Museum (岐阜かかみがはら航空宇宙博物館, nicknamed "Sorahaku") is located adjacent to the base. Originally opened in 1996 and extensively renovated and reopened in 2018, the museum occupies 9,400 square meters and houses Japan's largest collection of real aircraft — 41 actual planes and 15 full-scale models and replicas as of 2024. Highlights include a restored Kawasaki Ki-61-II-kai Hien, a full-scale replica of the Mitsubishi A6M Zero prototype (commemorating its 1939 first flight at this very location), and the Kawasaki Army Otsu-1 reconnaissance aircraft. The museum preserves and communicates the rich aviation heritage of a site that has been central to Japanese aviation for over a century.