Spaceflight Insider

Japan prepares to launch Kounotori-5 to Space Station

HTV-2_Kounotori_2_approaches_the_International Space Station NASA photo posted on SpaceFlight Insider

Archive photo of JAXA HTV spacecraft approaching the International Space Station. Photo Credit: NASA

Japan is poised to launch their fifth Kounotori vehicle to the International Space Station. The flight, originally scheduled for Aug. 17 but postponed due to unfavorable weather, is currently set to take place on Aug. 19, 2015, and it will deliver supplies to the International Space Station (ISS). The launch time is scheduled for 7:50 a.m. EDT (20:50 Japan Standard Time, JST).

The time of liftoff will likely change as the orbit of the ISS is updated closer to the flight time. Kounotori-5 (HTV-5) will ride atop the H-IIB Launch Vehicle No. 5, launching from the Yoshinobu Launch Complex on Tanegashima Island in Japan.

This launch is a joint operation between Mitsubishi Heavy Industries, Ltd., and the Japan Aerospace Exploration Agency (JAXA) to provide supplies, experiments, and equipment to the Expedition 44 crew members on board the ISS.

The upcoming flight will be the fifth time that JAXA has launched one of its HTV spacecraft to the ISS. Photo Credit: NASA posted on SpaceFlight Insider

The upcoming flight will be the fifth time that JAXA has launched one of its HTV spacecraft to the ISS. Photo Credit: NASA

As the vehicle’s designation implies, HTV-5 is the fifth in a series of spacecraft that made its debut during the HTV-1 test flight in September 2009. To date, all of the prior flights to the space station have been successful.

The Kounotori cargo vessels typically launch about once every year to a year-and-a-half. The most recent mission took to the skies on Aug. 4, 2013, with Kounotori-4 (HTV-4), which carried the first 4K camera into space among other items.

Meaning “white stork” in Japanese, Kounotori-5’s mission is much like other cargo spacecraft serving the space station, including Orbital ATK’s Cygnus and SpaceX’s Dragon. Measuring in at 32.1 feet (9.8 meters) long and 14.4 feet (4.4 m) in diameter, Japan’s “white stork” is much bigger than the other supply vehicles with the exception of the European Space Agency’s (ESA) Automated Transfer Vehicle (ATV).

The launch will be broadcast live courtesy of JAXA from their main launch complex from Tanegashima Space Center (TNSC). Thought to be the most beautiful launch site in the world, the island is located directly south of Kyushu, one of Japan’s main islands.

Once the H-IIB rocket and the HTV-5 spacecraft have launched, the No. 5 Launch Vehicle will cycle through its stage separations before inserting the capsule into an elliptical orbit.

As soon as separation from the H-IIB rocket has occurred, the spacecraft will automatically activate the HTV subsystems, initiating communications with the HTV Mission Control Room (HTVMCR) at Tsukuba Space Center (TKSC) near Tokyo, Japan.

This will be the fifth flight for the H-IIB Launch Vehicle, derived from the original H-II rocket that flew between 1994 and 1999. Two variants of the H-II were developed, including both the H-IIB and the H-IIA, which first flew in 2001. While the H-IIA has been the workhorse of Mitsubishi Heavy Industries, the H-IIB is specifically designated for HTV launches to the ISS.

The spacecraft’s delivery procedures are similar to the other cargo vehicles as well. Once inserted into the appropriate orbit, the HTV Pressurized Logistics Carrier will approach the International Space Station four days later on August 21 (if the new August 17 launch date holds).

JAXA describes the rendezvous sequence as such:

  1. After separating from the H-IIB launch vehicle, the HTV will automatically start-up the communication system and initiate communications with NASA’s Tracking and Data Relay Satellite (TDRS).
  2. The HTV status will be monitored from the HTVMCR at TKSC. It will take about three days for the HTV to reach close proximity to the ISS.
  3. When the HTV reaches the “proximity communication zone” (23 km from the ISS), the HTV will then be able to communicate directly with the ISS.
  4. The HTV will establish communications with the Proximity Communication System (PROX).
  5. While communicating with PROX, the HTV will approach the ISS guided by GPS signals until the HTV is 5 km behind the ISS. At this point, the HTV will maintain this distance from the ISS.

Slowly approaching the bottom side of the space station from Earth, Kounotori-5 will then move in to begin what is called the Berthing Phase on August 21.

Then, the vehicle’s thrusters will be disengaged to allow the Space Station Remote Manipulator System (SSRMS), also known simply as “Canadarm”, to grapple the HTV. ISS crew members can send commands to the HTV spacecraft such as HOLD, ABORT, or RETREAT should any anomaly occur during the process.

Once the spacecraft has successfully berthed with the International Space Station, the crew members can obtain the cargo.

The unique feature of Japan’s resupply vehicle is its ability to supply astronauts with both pressurized and unpressurized cargo within the mission. Out of a total cargo capacity (including both supplies and equipment) of 6.6 tons (6,000 kg), about 4.9 tons (4,500 kg) of that capacity can be pressurized.

A diagram showing the components of the HTV5/Kounotori5 spacecraft. Image Credit: JAXA

A diagram showing the components of the HTV-5/Kounotori-5 spacecraft. Image Credit: JAXA

Cargo included on the Kounotori-5 manifest as provided by JAXA is as follows:

  1. 600 liters of potable water
  2. Food
  3. Crew commodities
  4. Fluids Control and Pump Assembly (FCPA)
  5. Multifiltration Beds (WFB)
  6. Galley rack to be placed in Unity
  7. Simplified Aid for EVA Rescue (SAFER)
  8. Calorimetric Electron Telescope (CALET)

There is also scientific equipment included on board for experiments:

  1. Mouse Habitat Unit (MHU)
  2. Electrostatic Levitation Furnace (ELF)
  3. Multi-Purpose Small Payload Rack (MSPR-2)
  4. Exposed Experiment Handrail Attachment Mechanism (ExHAM 2)
  5. CubeSat (S-CUBE)

Among the current space station crew members that will receive Kounotori-5’s cargo is Kimiya Yui, a JAXA astronaut who was recently launched into space aboard a Soyuz spacecraft on July 23.

If everything goes according to plan the HTV-5 will rendezvous with the station at 7:55 a.m. EDT (11:55 a.m. GMT) on Aug. 21. It will then be grappled by the crew who will then berth it to the outpost. Installation should occur at around 10:45 a.m. EDT (14:45 GMT).

Like a handful of the other resupply spacecraft, Kounotori is not reusable but offers the ability to depose of waste materials for the crew. Kounotori-5 will remain berthed to the space station for almost a month, and then, at the conclusion of its stay on September 27, it will detach.

It can carry its full 6.6 ton capacity in waste material as it re-enters Earth’s atmosphere, estimated to occur on September 28, which will complete its journey. Despite burning up during re-entry, debris is expected to fall into the South Pacific Ocean and also, possibly, the Indian Ocean.

Additional launch windows for Kounotori-5 are between August 18 and September 30 with specific days and times to be determined in coordination with the space station.

Japan Aerospace Exploration Agency JAXA NASA Mitsubishi Heavy Industries H-IIB rocket photo credit JAXA posted on SpaceFlight Insider

An H-IIB at the Yoshinobu Launch Complex on Tanegashima Island in Japan. Photo Credit: JAXA

Please check back with Spaceflight Insider on updates on the upcoming Kounotori-5 launch.



Britt Rawcliffe is a professional freelance aerospace and aviation photographer based out of Pennsylvania with over six years of professional photographic experience. Her creative imagery has spanned into all areas relating to space, including launches, photojournalism, architecture, and portraiture. Britt’s passion for history has been a common thread in much of her work, including having photographed many Moonwalkers such as Buzz Aldrin and Gene Cernan.

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