H-II Transfer Vehicle
H-II Transfer Vehicle (HTV-1) approaching the ISS | |
| Country of origin | Japan |
|---|---|
| Operator | JAXA |
| Applications | ISS resupply |
| Specifications | |
| Spacecraft type | Uncrewed cargo vehicle |
| Launch mass | 16,500 kg (36,400 lb) |
| Dry mass | 10,500 kg (23,100 lb) |
| Payload capacity | 6,000–6,200 kg (13,200–13,700 lb) |
| Volume |
|
| Dimensions | |
| Length | ~9.8 m (32 ft) (including thrusters) |
| Diameter | 4.4 m (14 ft) |
| Production | |
| Status | Retired |
| Built | 9 |
| Launched | 9 |
| Maiden launch | 10 September 2009 (HTV-1) |
| Last launch | 20 May 2020 (Kounotori 9) |
| Related spacecraft | |
| Derivatives | HTV-X |
| Launch vehicle | H-IIB |
The H-II Transfer Vehicle (HTV), also called Kounotori (Japanese: こうのとり; lit. 'white stork'), was an expendable Japanese automated cargo spacecraft designed for International Space Station (ISS) resupply missions, particularly Kibō, the Japanese laboratory module.
Development of the spacecraft began in the early 1990s and the HTV's first mission, HTV-1, was launched on 10 September 2009 on an H-IIB launch vehicle. The HTV was crucial for ISS resupply, especially after the retirement of the Space Shuttle, as it was the only vehicle capable of transporting large International Standard Payload Racks (ISPR) and disposing of old ones within the ISS's US Orbital Segment. The final HTV mission, Kounotori 9, was launched on 20 May 2020. HTV's successor, the HTV-X, made its maiden flight in October 2025.