Boeing has begun assembling the fourth and final KC-46A flight-testing aircraft, the manufacturer’s next-generation aerial refuelling tanker replacement for the current fleet of KC-135 with the US Air Force. As per Boeing, the aircraft, a commercial derivative of the Boeing 767, will complete its first flight without the aerial refuelling systems in the near future. That flight will be followed by the first flight of the fully equipped test aircraft in early 2015. “All four test aircraft are moving through production to support our transition to ground and flight testing later this year,” said Maureen Dougherty, Boeing Vice-President and KC-46 Tanker Programme Manager. First delivery to the US Air Force is scheduled for early 2016.