H-II Transfer Vehicle KOUNOTORI (HTV)

HTV-1 continues nominal rendezvous maneuvering toward final approach phase

On Flight Day 8 (FD8), the HTV-1 is set to perform its final approach to the ISS.

On Flight Day 7 (FD7), the HTV-1 raised its orbit with a height adjustment maneuver. The HTV-1 is now flying in a near-circular orbit with apogee altitude 324 km and perigee altitude 305 km. During the FD8's rendezvous flight, the HTV-1 will perform two height adjustment maneuvers at 6:24 p.m. and 9:27 p.m. September 17 respectively to catch up to the ISS orbit.

Once the HTV-1 reaches "proximity communications zone", 23km from the ISS, the HTV-1 will establish communications with the Proximity Communication System (PROX) installed on Kibo, and will continue to approach using the Relative GPS Navigation. The HTV-1 is expected to reach the "Approach Initiation (AI) point", 5 km behind the ISS, at 10:59 p.m. September 17.

At 0:30 a.m. September 18, the HTV-1 will begin to move from the AI point to a point 500 meters below the ISS (RI point). From the RI point, the nadir side of the ISS, the HTV-1 will slowly move to the ISS.

HTV-1's Proximity Operations Profile on FD8

When the HTV-1 reaches 10 m below the ISS, the HTV thrusters will be disabled. Then, the ISS Expedition 20 Flight Engineer Nicole Stott will manipulate the station's robotic arm (SSRMS) and grapple the HTV-1 at around 4:50 a.m. September 18. The berthing operations is expected to begin at around 7:00 a.m. September 18.

During these robotics operations, JAXA Astronaut Akihiko Hoshide will be on console at the Mission Control Center (MCC-H) of NASA's Johnson Space Center (JSC) as ISS CAPCOM. He will support the operations from the ground.

We will start the next HTV-1 Mission update from 0:00 a.m. September 18, with live blogging on the HTV-1's final approach / capturing / berthing.

*All times are Japan Standard Time (JST. UTC + 9 hours)