Kounotori-5, the fifth HTV (H-2B Transfer Vehicle), has been launched from Tanegashima Space Center in Japan, aboard the beefy H-2B rocket, loaded with supplies for the ISS that are now even more critical than ever after a string of failures grounded the other two large cargo vehicles. (Progress made a successful run, but is smaller, with a standard Soyuz cone-and-drogue hatch. HTV, Cygnus, and Dragon all make use of the spacious Common Berthing Adapters instead, allowing delivery of larger payloads.) Kounotori-5 is now making its gradual approach to the ISS, and in a couple of days will be captured by the SSRMS, operated by JAXA astronaut Kimiya Yui, and berthed at the station. It will be the last flight to the US segment until Cygnus returns to flight in December.
HTV is scheduled to make another flight next year, and then fly about annually thereafter. By internal volume, it is one of the largest of the cargo vehicles that flies to the ISS (second largest by pressurized volume, largest by upmass — ATV was larger in both but is no longer flying, and of course Shuttle won overall), and this flight alone will deliver enough consumables to keep the ISS operating into next year even if there is no more resupply in 2015. Like Dragon, it is able to carry unpressurized payloads as well, but unfortunately not as much space is devoted to this unpressurized section and so it cannot duplicate Dragon’s role in delivering the new docking adapters. But its mission is nevertheless critical.
Congratulations on an excellent launch, Japan!
Both HTV and the H-2B rocket are joint efforts between JAXA and their manufacturer, Mitsubishi Heavy Industries.