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Japan’s indigenous H-2B rocket successfully launched the HTV cargo transporter on September 11 for a week long voyage to the ISS. The launch vehicle flew smoothly, and at 15 minutes and 6 seconds after liftoff, the separation of the HTV Demonstration Flight was confirmed.The HTV was designed by the Japan Aerospace Exploration Agency (JAXA) to transport supplies to the ISS. On this demonstration mission, the HTV is carrying 4.5 tonnes of food and supplies, and was scheduled to dock with the ISS on September 18. Launched from the JAXA Space Centre at Tanegashima Island off Kyushu, the H-2B launcher can lift 16.5 tonnes into low earth orbit. The H-2B launch vehicle is a two-stage rocket using liquid oxygen and liquid hydrogen as propellant and has four strap-on solid rocket boosters (SRB-A) powered by polibutadiene.

HTV arrived at the ISS on September 18, and was captured with the Space Station Remote Manipulator System (SSRMS), known as “Canadarm2″ when it approached to just 9 metres. The arrival of the HTV on its maiden flight was more than a triumph for Japan. It also proved that the capture of an independently powered spacecraft is within the capability of the ISs crew.

Both Russia’s Progress and the ESA ATV cargo transport ships feature automatic docking. The capture of HTV was an important event because it will need to be repeated often in the future, as Japan takes a more active role in supplying the ISS. While the HTV is berthed to the ISS, the ISS crew will be able to enter and remove the s

upplies from the HTV Pressurized Logistics Carrier.

After the supplies, such as food, clothes and a variety of experiment equipment are unloaded, the HTV will then be loaded with waste materials, including used experiment equipment or used clothes. The HTV will then undock and separate from the ISS then disintegrate as it reenters the Earth’s atmosphere.

In addition to Russia’s cargo spacecraft, Progress, the U.S. Space Shuttle (soon to be retired), the Automated Transfer Vehicle (ATV), developed and built by the European Space Agency (ESA), Japan’s HTV will be utilized for delivering supplies to the ISS. Among these cargo-carrying spacecraft, the HTV is the only unmanned vehicle that can carry both pressurized and unpressurized cargo.