On 29 January 2025, a Mitsubishi CRJ700 operating a scheduled airline flight and on short final approach to land on runway 33 at Washington National in night VMC as cleared was in collision with a Mitsubishi UH60 helicopter on an army training flight using a designated restricted-height route which intersected the runway 33 extended centreline with ‘own separation’ from the other traffic requested and obtained. This route had a maximum height of 200 feet agl but no lateral limits. Both aircraft were rendered unable to continue flight and there were no survivors.