JAPAN - Progress is being made in plans that would allow flights of large aircraft to and from Haneda Airport to fly over the centre of Tokyo.
The aim of the plans, which would end an unwritten rule banning flights of large aircraft over the capital, is to increase the number of arrivals and departures at the airport ahead of the 2020 Tokyo Olympics and Paralympics.
Attention is focused on certain envisaged flight paths over such areas as Shibuya and Shinagawa wards that would be used for landings, although these routes would be only used during the afternoon in southerly winds, mainly in the summer.
The Land, Infrastructure, Transport and Tourism Ministry is cautiously preparing to establish the flight paths over the heart of Tokyo, which would end the ministry's seemingly self-imposed ban on such flights.
Haneda Airport has two pairs of parallel runways. Most flights to and from Haneda currently use routes that include an area over Tokyo Bay, an arrangement made to bypass airspace over the heart of Tokyo.
Consequently, the airport can only accommodate up to 80 arrivals and departures per hour at the present time.
By the opening of the 2020 Olympic Games, the government hopes to double the number of foreign tourists visiting the nation to 20 million annually. This will call for a further increase in the number of flights to and departures from Haneda.
A related task is how to accommodate arrivals and departures in southerly winds, a weather condition that is frequently observed from early spring to summer.
Because takeoffs and landings must be carried out against the wind, the current routes using airspace over Tokyo Bay require planes to approach Haneda from the direction of Chiba Prefecture and then take a sharp left turn immediately before landing.
Allowing aircraft to descend over the centre of Tokyo would enable more efficient use of Haneda's runways. According to a ministry estimate, utilizing the central Tokyo routes would make it possible to accommodate 90 arrivals and departures per hour at Haneda.
Under the envisaged flight paths, planes would be able to make a beeline from an area over Saitama to Haneda, gradually descending toward the airport. They would fly at an altitude of less than 1,000 meters near the Tokyo metropolitan government office, and descend to less than 500 meters in the vicinity of Shinagawa Station after passing through airspace over areas around Shibuya Station.
Noise pollution concerns
This has raised concerns about noise pollution, because using the envisaged routes means large passenger aircraft would fly at an altitude lower than the 634-meter-high Tokyo Skytree.
Noise levels register an average of about 77 decibels when a Boeing 777-200, one of the world's largest passenger planes, flies at a height of about 400 meters above residential areas before landing at Osaka Airport in Itami, Hyogo Prefecture. The noise inside a subway train carriage reaches about 80 decibels, according to the ministry.
"Engine noise from a state-of-the-art plane would be lower," an official of the ministry's Civil Aviation Bureau said.
In August, the ministry explained its flight rerouting plan to local governments to be affected by the project. There are about 20 kinds of new planned routes to and from Haneda, including one requiring planes to fly over Kawasaki when taking off. Tokyo, Kanagawa and three other neighbouring prefectures would be affected.