TOKYO -- A 1999 agreement between Japan and the U.S. that requires the use of altitude criteria stipulated by Japan's aviation law does not apply to rotorcraft (helicopters), United States Forces Japan told the Mainichi Shimbun.
Low-altitude flights of U.S. military helicopters has been a problem in Japan's southernmost prefecture of Okinawa and elsewhere in the country, but this means that U.S. helicopters have been exempt from the bilateral agreement, which has a deterrence effect.
Meanwhile, the Japanese government has explained that aircraft, regardless of type, are subject to the agreement -- an explanation that differs from the U.S. military's take on the pact. This means that there is a possibility that low-altitude flights of U.S. military helicopters have been carried out repeatedly amid differing interpretations of the agreement between the two countries.
According to Japan's Civil Aeronautics Act, the minimum safety altitude is set at 300 meters above the highest building within a 600-meter radius in highly concentrated areas, meaning planes must fly higher than that.
Due to a special aviation law based on the Japan-U.S. Status of Forces Agreement (SOFA), the U.S. military in Japan is not subject to Japan's minimum safety altitude. With consideration for the issue of low-altitude flights, Tokyo and Washington reached a deal on training of such flights at a January 1999 meeting of the Japan-U.S. Joint Committee as part of U.S. military operations in Japan. The committee had disclosed six items from the agreement, including requiring the application of the minimum safety altitude stipulated by the International Civil Aviation Organization (ICAO) and Japan's aviation law, and paying appropriate considerations toward highly-populated areas and areas that have to do with public safety, such as schools and hospitals.
However, even after this agreement was reached, low-altitude flights by U.S. military aircraft including helicopters have been witnessed repeatedly in Okinawa and other places. Since July 2020, the Mainichi Shimbun has taken photos and videos over 20 times of U.S. military helicopters flying over Shinjuku Station in Tokyo and other areas in the capital's center at an altitude of less than 300 meters.
In response to a Mainichi question about the possibility that the U.S. military was violating its 1999 agreement with Japan, U.S. Forces Japan argued in a letter that the pact was about fixed-wing jets, and that because rotorcraft (helicopters) differ from fixed-wing jets in flight characteristics and requirements, the agreement does not apply to them. In addition, U.S. Forces Japan stated that it was observing the bilateral agreement reached by the joint committee, but because it did not clarify what the specific contents of the pact were, it is unclear what rules it is adhering to.
Meanwhile, the Japanese Ministry of Foreign Affairs' Status of U.S. Forces Agreement Division has a different interpretation from the U.S. of the bilateral agreement. When Constitutional Democratic Party of Japan legislator Keisuke Tsumura asked Foreign Affairs Minister Toshimitsu Motegi during the March 19 meeting of the House of Representatives Committee on Foreign Affairs whether helicopters were subject to the 1999 agreement, Motegi refrained from making a clear statement on the Japanese government's position and said, "There are no definitions (of aircraft that are subject to the deal)."
As for the difference in interpretation of the pact between Tokyo and Washington, the foreign ministry division has said, "It may be a matter of how we read the agreement document." But with a provision in the SOFA that the U.S. military must respect Japanese laws in mind, the division explained, "Even if the U.S. military says, 'helicopters are not subject' to the agreement, they are obligated to respect Japanese laws."
At a meeting of the House of Representatives Committee on Land, Infrastructure, Transport and Tourism, minister Kazuyoshi Akaba, who oversees aviation administration, was asked whether the rules prohibited U.S. military helicopters from flying at altitudes that violate aviation law. To this, Akaba answered, "That is the case."
(Japanese original by Hiroyuki Oba, City News Department, and Tamami Kawakami, Foreign News Department)