Michibiki satellite system to assist aircraft landings

​TOKYO (The Japan News/ANN) - To assist with aircraft landings, the Land, Infrastructure, Transport and Tourism Ministry has planned to utilise the Michibiki positioning satellite constituting a network known as the Japanese version of the Global Positioning System.

The Land, Infrastructure, Transport and Tourism Ministry plans to utilize the Michibiki positioning satellite (see below), constituting a network known as the Japanese version of the Global Positioning System, to assist with aircraft landings, The Yomiuri Shimbun has learned. The ministry will build a system for assisting aircraft, investing a total of about ¥16 billion over five years starting in fiscal 2020. 
 Positioning information from the Michibiki satellite is said to be accurate with a margin of error of a few centimeters. With such precise information, pilots will be able to acquire more accurate location information, which would help to improve such airport operations as reducing the number of reattempted landings.
 Four Michibiki satellites were launched and have been in operation for defense and disaster-related purposes. Their location information is much more accurate than that of the multifunctional transport satellites aircraft currently use. 
 The ministry plans to make one Michibiki satellite available for aircraft use this spring and to increase the number to three by fiscal 2025. Such a system would lower the altitude at which pilots decide whether or not to make a landing. 
 Under current rules, the decision for a landing must be made by the time an aircraft descends to 75 meters above ground, but it is expected that the new system could lower the threshold to 60 meters. 
 Lowering the decision altitude would make it easier for pilots to visually confirm runway conditions during cloudy or foggy weather, and reduce the number of aborted and reattempted landings due to bad weather. 
 In addition to satellites, aircraft obtain information from instrument landing systems (ILS) installed at airports. While ILS can enhance the safety and efficiency of flights, they are expensive. Therefore, many airports, especially regional ones, are not equipped with ILS. The ministry thus hopes that using the Michibiki satellites will contribute to reducing flight schedule disruptions. 

■ Michibiki positioning satellite
 Satellite for Japan’s high-precision positioning system. The Cabinet Office has been operating the system with a deployment of four satellites since November 2018. Because the satellites are flying in the orbit near the zenith of Japan, they are capable of sending positioning signals that are not blocked by high-rise buildings or other such objects. The office plans to increase the number of Michibiki satellites to seven by fiscal 2023.