H-II Transfer Vehicle

HTV

Mission Profile

H-II Transfer Vehicle (HTV, Kounotori or White Stork) is JAXA's uncrewed cargo spacecraft designed to supply the International Space Station with pressurized and unpressurized cargo, launched aboard H-IIB rockets from Tanegashima Space Center. First flown in September 2009, the 16.5-tonne vehicle is significantly larger than NASA's Dragon or ESA's ATV, capable of delivering up to 6,000 kg of supplies including large external payloads on its exposed aft section. HTV is unique in approaching the ISS for capture by the Canadarm2 robotic arm rather than docking autonomously, and it carries science racks, experiment hardware, and even replacement batteries for the station's solar power system. Seven HTV missions were completed between 2009 and 2020, fully demonstrating Japan's capability in autonomous orbital rendezvous operations.