The US is converting Cold War-era helicopters into drones, a move defence experts say could play a “critical role” in any conflict with Beijing over the Taiwan Strait. The PLA has also been retrofitting outdated aircraft to act as uncrewed drones, with both militaries unveiling similar systems within a month of each other last year. The S-70UAS U-Hawk, a fully autonomous helicopter based on the UH-60 Black Hawk, was first showcased last October at an annual American military event, where it was...