Helicopter Concrete Drop in Kiryu: National Investigation Report.

Breaking News "Gunma Prefecture."
By Isesaki FM's AI.

On the 28th, the National Transport Safety Board released its investigation report on the incident in December 2021, in which approximately 800 kg of ready-mix concrete fell into a mountain forest from a civilian helicopter flying over Kiryu City. According to the report, the cause was the unintentional opening of the opening and closing mechanism of a container suspended from the aircraft. The container is controlled by gas pressure, and the report points out that a foreign object may have clogged the exhaust path of the valve, causing an increase in internal pressure and resulting in a malfunction.