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H-II Transfer Vehicle KOUNOTORI (HTV)

Last updated: June 12, 2012

Features of KOUNOTORI3

KOUNOTORI3 adopts domestically developed equipment

Following equipments of KOUNOTORI (HTV3) have developed in Japan for full-scale operation and utilization in the future. Through the process of manufacturing KOUNOTORI in Japan, technology which is imperative for inter-orbit transportation, cost reduction, and stable procurement become possible.

Propulsion module
  • Main engine
  • RCS thruster

Avionics module
  • Transponder
  • Diplexer

Main engine

Main engine

RCS thruster

RCS thruster

Improves convenience for the expanded utilization of the ISS

The amount of late loading cargo has increased as a result of accumulated know-how learned through the loading in the HTV1 and HTV2. This makes the delivery plan more flexible and enables to meet the users' needs.

Further, Exposed Pallet-Multi-Purpose (EP-MP) has been newly developed. EP-MP is able to load various unpressurized cargo other than Kibo's payload and expected to meet various types of delivery requirements for the unpressurized payload and ORUs.



Loading Re-entry Data Recorder (i-Ball)



Under the cooperation between JAXA and private sector, i-Ball is scheduled to be loaded in the KOUNOTORI3. i-Ball could gather the reentry environmental data. The data analysis will lead to an identification of breakup phenomenon of the vehicle and decrease in the reentry debris risks. At the same time, another purpose is to obtain design data for the future reentry vehicles.

Wide range of data acquisition is expected in conjunction with NASA's ReEntry Breakup Recorder (REBR).

i-Ball overview
Name i-Ball
Developer IHI AEROSPACE Co.,Ltd.
Obtainable data Temperature
Acceleration/ angular velocity
Still photos
GPS Navigation data (for an altitude of under 50km)
Total Mass 15.5 kg (17kg, including cover)
Diameter outside diameter Φ400mm (410×440×435mm, including container)
Landing system Splashdown after decelerated by a parachute opening

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