HTV 1

Payloads

HTV-1 carried four and a half tonnes of payload, lower than the six tonne maximum payload of the HTV in order to allow the spacecraft to carry additional propellant and batteries for the in-orbit verification phase of the flight.

In the Unpressurised Logistics Carrier, the HTV-1 carried SMILES (Superconducting Submillimetre-Wave Limb Emission Sounder) and HREP (HICO-RAIDS Experiment Payload), which both were installed in the JEM Exposed Facility on the ISS. The Pressurised Logistics Carrier carried 3.6 tonnes of supplies for the International Space Station. It consisted of food (33% of weight), laboratory experiment materials (20%), robot arm and other hardware for JEM (18%), crew supplies including garments, toiletries, personal mail and photographs, fluorescent lights, waste buckets (10%), and packing materials (19%).

Carrier rocket

HTV-1 was launched on the maiden flight of the H-IIB carrier rocket. The H-IIB 304 configuration was used, with a type 5S-H payload fairing. Before launch, two Captive Firing Tests were conducted on the rocket which was to launch HTV-1. The first test, which consisted of firing the first stage for ten seconds, was originally scheduled to occur at 02:30 UTC on 27 March 2009, however it was cancelled after the launch pad's coolant system failed to activate. This was later discovered to have been due to a manual supply valve not being open. The test was rescheduled for 1 April, but then postponed again due to a leak in a pipe associated with the launch facility's fire suppression system. The test was rescheduled for 2 April, when it was successfully conducted at 05:00 UTC. Following this, the second test, which involved a 150-second burn of the first stage, was scheduled for 20 April. This was successfully conducted at 04:00 UTC on 22 April, following a two-day delay due to unfavourable weather conditions. A ground test, using a battleship mockup of the rocket was subsequently conducted on 11 July.

Launch and rendezvous with ISS

HTV-1 was successfully launched at 17:01:46 UTC on 10 September 2009, to the initial orbit of 299.9 km apogee / 199.8 km perigee / 51.69° inclination (planned 300.0 ±2 km / 200.0 ±10 km / 51.67 ±0.15°). The launch took place from the Yoshinobu Launch Complex at the Tanegashima Space Centre, and was the first to use the second pad of the complex.

Flight operations are chronicled using Flight Day (FD), the ISS crew timeline. Arrival of HTV-1 occurred during Expedition 20, (Gennady Padalka, Commander, Michael Barratt, Nicole Stott, Frank De Winne, Roman Romanenko, and Robert Thirsk). Expedition 21 supervised Departure of HTV-1, (Frank De Winne, Commander, Roman Romanenko, Robert Thirsk, Maksim Surayev, Jeffrey Williams, and Nicole Stott). The station was visited by Spaceflight Participant Guy Laliberté. No Japanese astronaut was present during the attached phase of the HTV-1 to the ISS.The launch day is FD1. On FD3 (September 12), HTV-1 performed the demonstration tests of ISS proximity operation such as collision avoidance manoeuvre. It went successfully and on FD6, ISS Mission Management Team approved the final approach.

On 17 September, HTV-1 rendezvoused with the International Space Station. It arrived at the Approach Initiation Point, 5 kilometres behind the space station at 13:59 UTC, and began its final approach sequence at 15:31. It approached to within 10 metres (33 ft) of the station, from where it was grappled using the Canadarm2 robotic arm of the space station, operated by Nicole Stott. Initial capture occurred at 19:47 UTC, with the procedure being completed at 19:51. Robert Thirsk then used Canadarm2 to move it to a "ready-to-latch" position over the nadir CBM port of the Harmony module. It arrived at this position at 22:08 UTC, and by 22:12 four latches had engaged to hold it in place. Sixteen bolts were subsequently driven in to achieve a hard mate. It remained berthed at the station until October 30.

Departure from the ISS and Re-entry

Expedition 21 crew members, Nicole Stott, Robert Thirsk and Frank De Winne completed the final steps of preparing for HTV's release from the ISS. These steps included disconnecting the final remaining power jumper line, closing the Node-2 nadir hatch, depressurizing the vestibule & performing leak checks, removing Common Berthing Mechanism bolts and deploying latches and unberthing the HTV-1 with the Space Station Remote Manipulator System.

While passing above the Pacific Ocean, the robotic arm of the space station released the HTV-1 positioned at 12m below the station on 30 October 2009. The departure was delayed for one ISS orbit to avoid debris (COSMOS 2421). HTV-1 was loaded with 199 items of discarded equipment & waste of 727.7 kg, as well as 896 kg empty racks, totaling 1,624 kg. At 17:32 (UTC), HTV-1 was released from SSRMS and began its planned maneuvers to leave the station proximity. HTV-1 gradually departed from the ISS orbit by performing several thruster burns and entered to its solo-flight mode.

The HTV flight control team sent commands for three engine burns at 14:55, at 16:25, and at 20:53, November 1 (UTC) to prepare the vehicle's destruction in Earth's atmosphere. The first de-orbit engine burn lasted for approximately 8 minutes and was completed at 15:03, November 1. The second de-orbit engine burn lasted for approximately 9 minutes and was completed at 16:34. Following the second de-orbit maneuver, the HTV-1 was inserted into an elliptic orbit with an altitude of 143 km perigee and 335 km apogee.

HTV-1 began the third and final de-orbit maneuver at 20:53 on November 1 as planned, while the spacecraft was passing over Central Asia. The maneuver that lasted for about 8 minutes was successfully wrapped up at 21:01 as the spacecraft flew near the southern half of Japan. According to the Japan Aerospace Exploration Agency, HTV-1's atmospheric re-entry occurred at 21:25. at 120 km above and over the Pacific Ocean just off the coast of New Zealand. The fiery re-entry and disintegration in the Earth's atmosphere marked the successful completion of the HTV-1's 52 day mission.

It is believed that some of the surviving debris from the HTV would have likely fallen in a rectangular area stretching across the Pacific Ocean between New Zealand and South America, according to the Japan Aerospace Exploration Agency.