Airport Low-level Wind Information (ALWIN) starts operation at Haneda and Narita airports

April 19, 2017 (JST)

Airport Low-level Wind Information (ALWIN) starts operation at Haneda 
and Narita airports

"Airport Low-level Wind Information (ALWIN)", jointly developed by 
the Japan Meteorological Agency (JMA) and the Japan Aerospace 
Exploration Agency (JAXA), starts operation today at Tokyo 
International Airport (Haneda) and Narita International Airport. 
ALWIN provides low-level wind information (wind direction, wind speed, 
wind shear*, turbulence, etc.) around airports. While JMA's existing 
wind shear alert system uses radio voice communication to convey only 
minimum information about detected wind shears, the newly introduced 
ALWIN can transmit more detailed and precise wind profiles on final 
approach paths in real-time. This helps pilots and operators to 
monitor sudden changes in winds on approach and landing paths. 
Accordingly, safer landing operations become possible with ALWIN. 
This is the first case in the world where such an advisory system for 
low-level wind disturbances is put into actual service.

Low-level wind shears and turbulence often endanger flight safety and 
efficiency. In fact, roughly 100 go-arounds occur every year at 
Narita International Airport, causing an average of 20 minutes' delay 
in arrival for each go-around. Around 90 percent of these go-arounds 
are caused by low-level wind shears and turbulence. Also, in the past 
10 years, two turbulence induced accidents during landing approach 
were reported at Narita, resulting in injury or death to crews and 
passengers. The introduction of "ALWIN" to Narita and Haneda will help 
improve air safety and reliability for on-time arrivals and departures. 

JAXA is going to evaluate the actual effects of ALWIN implemented at 
these two airports. JAXA is also developing a low-cost version based 
on ALWIN technology.  

*Wind shear: Sudden changes in wind speed and/or direction, tends to 
occur near low pressure systems and fronts.

How ALWIN works: Information provision flow


National Research and Development Agency Japan Aerospace Exploration 
Agency (JAXA)