Ukraine war becomes a testing ground for drones that can evade jamming systems

In a field on the outskirts of Kharkiv, Ukraine, a drone buzzes through the air as a soldier sitting in the back of a truck uses a controller to steer it during a test flight. For several months, Krab, who is only being identified by his call sign in keeping with Ukrainian military rules, has been using drones fitted with munitions, such as grenades, to target Russian troops and equipment. But this drone carries another fixture: A thin spool containing a 15-kilometre fibre-optic cable that unrav