Six months have passed since the large-scale urban fire in Saganoseki, Oita City, in November 2025. I would like to offer my deepest condolences to the bereaved family of the victim and express my heartfelt sympathies to all those affected and still enduring evacuation.
On May 18, 2026, NHK News (web article and news broadcasts) featured our joint research findings on the fire spread analysis using a 3D model developed collaboratively by Professor U Hiroi (The University of Tokyo) and NHK.
This 3D model digitally reconstructed the post-disaster site based on spatial data captured during our drone (UAV) survey conducted approximately one month after the fire.
The 3D analysis visually confirmed that ember/firebrand spotting driven by strong winds travelled over 150 meters from the main fire front, penetrating roof tiles and wall crevices to expand the fire. Conversely, the model clearly illustrated that wider roads capable of vehicular access and open spaces effectively suppressed fire spread by blocking radiant heat and facilitating firefighting operations.
As aging populations and unmanaged vacant houses increase vulnerability in dense wooden districts, these spatial insights provide crucial lessons for building fire-resilient communities and guiding disaster recovery planning. The commentary video and full article using the 3D imagery are available on NHK's official website.
- NHK News : https://news.web.nhk/newsweb/na/na-k10015124401000
- Drone Survery Report: https://jafse.smoosy.atlas.jp/ja/firenews20260108
