[KC-390 Millennium](https://defence24.pl/industrial/new-airplanes-for-Sweden-embraer-c-390-replaced-selected-hercules) already has the anticipation of downloading and transferring fuel in the air. However, it can only carry out this transfer with 2 sloping flexible wires. This solution requires an aeroplane to draw fuel to have a peculiar ejected or permanently mounted sampling probe. This solution is given by machines of all countries in the planet outside the world's largest air force, the U.S. Air Force (U.S. Navy and U.S. Marine Corps besides usage probes and flexible wires).