JAXA Launches HTV7 Unmanned Cargo Spacecraft on Resupply Mission to ISS

The HTV7 unmanned cargo spacecraft is carrying six metric tons of equipment and supplies, including much-needed lithium-ion batteries, on this resupply mission to the ISS.

The Japan Aerospace Exploration Agency (JAXA) H-IIB Launch Vehicle No. 7 lifted off from the Tanegashima Space Center in Japan at 2:54:27 Japan Standard Time (JST) on September 23, carrying the KOUNOTORI7 (HTV7) cargo transporter into orbit to start its journey to the International Space Station (ISS).

The HTV7 unmanned cargo spacecraft  is carrying six metric tons of equipment on this resupply mission to the ISS. Developed and built in Japan, the H-II Transfer Vehicle (HTV) known as "KOUNOTORI,” which means “white stork” in Japanese, boasts the world’s largest loading capacity, officials say, and such unique functions as the International Standard Payload Racks (ISPRs) and unpressurized cargo transport.

The launch vehicle flew smoothly and 14 minutes and 59 seconds after liftoff, after which the separation of the HTV7 was confirmed. The HTV7 will gradually get closer to and will be berthed at the ISS.

KOUNOTORI7 soon established communications with the NASA's Tracking and Data Relay Satellite (TDRS) and then initiated communications with the HTV Mission Control Room (HTV MCR) at the Tsukuba Space Center (TKSC).

KOUNOTORI7 established three-axis attitude at 03:50 a.m., September 23, and system self-checks were ongoing in preparation for its first phase adjusting maneuver (Phase Maneuver1: PM1).

KOUNOTORI7 completed its first Phase Maneuver (PM1) at 10:29 a.m., September 23.

HTV7 will deliver a total of 6.2 metric tons of cargo to the ISS, including 4.3 metric tons in the Pressurized Logistic Carrier (PLC) and 1.9 metric tons on the Unpressurized Logistic Carrier (ULC). The cargo payload to be delivered on board HTV7 includes:

Cargo in the Pressurized Logistics Carrier (PLC)

  • HTV Small Re-entry Capsule: HSRC
  • Utilization/experiment-related items
    • Racks
      • Express Rack 9B
      • Express Rack 10B
      • Life Support Rack: LSR (ESA Payload)
      • Life Sciences Glovebox (LSG) and LSG Launch support rack
    • Loop Heat Pipe Radiator: LHPR
  • Cargo for the onboard crew
    • Fresh Food
    • Crew Provisioning Items

Cargo in the Unpressurized Logistics Carrier (ULC)

  • ISS Li-ion battery orbital Replacement Units (ORUs)

Cargo in the pressurized Logistic Carrier (PLC)

Experiment racks

Two US experiment racks (Express Rack 9B and 10B)

US EXPRESS Racks 9B and 10B will be delivered on this flight. These two EXPRESS Racks are modified for more simple interfaces.

US Life Sciences Glovebox (LSG)

Life Sciences Glovebox (LSG), the second ISS large-scale glovebox for scientific experiments, will be installed on board Kibo, the Japanese Experiment Module (JEM) on the ISS.

Life Support Rack (LSR)

The Life Support Rack (LSR) developed by the European Space Agency (ESA) is equipment for demonstration test of effective life support system which produces oxygen (O2) from water (H2O) by using electrolysis and also converts the produced hydrogen (H2) in Sabatier reaction with carbon dioxide (CO2), removed from the inside of the cabin, into methane (CH4) and byproduct water (H2O), which is then recycled for electrolysis.

Utilization/experiment-related items

HTV Small Re-entry Capsule (HSRC)

HTV Small Re-entry Capsule (HSRC) will demonstrate reentry technology and cargo recovery function from the ISS. HSRC with experiment samples will be attached to the hatch of the Pressurized Logistic Carrier (PLC) before the HTV7 unberthing from ISS. HSRC will separate from the HTV7 after its deorbit burn, re-enter Earth’s atmosphere, descend by parachute, and be recovered after splashdown.

Loop Heat Pipe Radiator (LHPR) technology demonstration system

The Loop Heat Pipe is expected for high-efficiency heat rejection technology for future spacecraft. This Loop Heat Pipe Radiator (LHPR) demonstration will perform on-orbit technology demonstration of an expansion-type radiator equipped with a loop heat pipe by using Kibo as a test bed environment. The demonstration aims to reduce risks in satellite development by reflecting the results obtained by the on-orbit demonstration to the design of the expansion-type radiator, which will be applied to Engineering Test Satellite-9 aimed at the realization of next-generation geostationary communications satellites.

JEM Small Satellite Orbital Deployer (J-SSOD) and CubeSat

This mission will mark the 10th CubeSat deployment using JEM Small Satellite Orbital Deployer (J-SSOD) since 2012.

HTV7 will deliver CubeSats developed by a joint team of Nanyang Technological University (NTU, in Singapore) and Kyushu Institute of Technology (Kyutech, in Japan), general incorporated association Rymansat Spaces, and Shizuoka University.

The SPATIUM-I (2U sized) CubeSat will perform a mission to demonstrate technology aimed at electron density measurement and three-dimensional mapping of ionosphere and chip scale (ultra-small) atomic clock for CubeSats.

The RSP-00 (1U sized) CubeSat will demonstrate technology for imaging with onboard camera and high-speed data transmission.

The STARS-Me (2U sized) CubeSat from Shizuoka University will perform small-scale demonstration of space elevator, which is a demonstration mission of configuration of two satellites and a climber (moving mechanism).

Fresh food for the onboard crew

HTV7 will deliver foods and other supplies including fresh food.

Cargo on the Unpressurized Logistic Carrier (ULC)

ISS battery Orbital Replacement Units (ORUs) on Exposed Pallet (EP)

Following the HTV6, the HTV7 (and also HTV8 and HTV9) will deliver new lithium-ion batteries for ISS on the Exposed Pallet (EP) on the Unpressurized Logistic Carrier (ULC). New six battery ORUs consisting of new lithium-ion battery cells manufactured by a Japanese company are delivered.

The nickel-hydrogen batteries currently used on the ISS are becoming old. The extension of ISS operations becomes possible with the supply of Japanese lithium-ion battery cells. Only the HTV is capable of delivering six battery ORUs at one time, and plays an important role in continuous ISS operations.

Courtney E. Howard  is editorial director and content strategist at SAE International, Aerospace Products Group. Contact her by e-mail at This email address is being protected from spambots. You need JavaScript enabled to view it..