The H-I or H-1 was a Japan

Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

ese liquid-fuelled carrier rocket, consisting of a licence-produced American

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 first stage and set of booster rocket

Booster rocket

A booster rocket is either the first stage of a multi-stage launch vehicle, or else a strap-on rocket used to augment the core launch vehicle's takeoff thrust and payload capability. Boosters are generally necessary to launch spacecraft into Earth orbit or beyond...

s, and all-Japanese upper stages. It was launched nine times between 1986 and 1992. It replaced the N-II

N-II (rocket)

The N-II or N-2 was a derivative of the American Delta rocket, produced under licence in Japan. It used a Thor-ELT first stage, a Delta-F second stage, nine Castor SRMs, and on most flights either a Star-37E or Burner-2 upper stage, identical to the US Delta 0100 series configurations...

, and was subsequently replaced by the H-II

H-II

The H-II rocket was a Japanese satellite launch system, which flew seven times between 1994 and 1999, with five successes. It was developed by NASDA in order to give Japan a capability to launch larger satellites in the 1990s. It was the first two-stage liquid-fuelled rocket Japan made using only...

, which used the same upper stages with a Japanese first stage.

The first stage of the H-I was a licence-built version of the Thor-ELT, which was originally constructed for the US Delta 1000

Delta rocket

Delta is a versatile family of expendable launch systems that has provided space launch capability in the United States since 1960. There have been more than 300 Delta rockets launched, with a 95 percent success rate. Two Delta launch systems – Delta II and Delta IV – are in active use...

 rocket. The stage had already been licence produced in Japan for the N-I

N-I (rocket)

The N-I or N-1 was a derivative of the American Delta rocket, produced under licence in Japan. It used a Thor-ELT first stage, a Mitsubishi Heavy Industries-designed LE-3 engine was used as a second stage, and three Castor SRMs. Seven were launched between 1975 and 1982, before it was replaced by...

 and N-II

N-II (rocket)

The N-II or N-2 was a derivative of the American Delta rocket, produced under licence in Japan. It used a Thor-ELT first stage, a Delta-F second stage, nine Castor SRMs, and on most flights either a Star-37E or Burner-2 upper stage, identical to the US Delta 0100 series configurations...

 rockets. The second stage was entirely Japanese, using an LE-5

LE-5

The LE-5 liquid rocket engine and its derivative models were developed in Japan to meet the need for an upper stage propulsion system for the H-I and H-II series of launch vehicles. It is a bipropellant design, using LH2 and LOX. Primary design and production work was carried out by Mitsubishi...

 engine. On launches to Geosynchronous transfer orbits, a Nissan-produced UM-129A solid motor was used as a third stage. Depending on the mass of the payload, either six or nine US Castor 2 SRMs would be used as booster rocket

Booster rocket

A booster rocket is either the first stage of a multi-stage launch vehicle, or else a strap-on rocket used to augment the core launch vehicle's takeoff thrust and payload capability. Boosters are generally necessary to launch spacecraft into Earth orbit or beyond...

s.

Launch history

Date/Time (GMT)	S/N	Payload	Orbit	Remarks
12 August 1986, 20:45	15(F)	EGP Experimental Geodetic Payload The Experimental Geodetic Payload is a Japanese satellite sponsored by NASDA, and launched in 1986 on the first flight of the H-I rocket. After launch, the satellite was renamed Ajisai , but it is most commonly known by the acronym EGP...  (Ajisai Experimental Geodetic Payload The Experimental Geodetic Payload is a Japanese satellite sponsored by NASDA, and launched in 1986 on the first flight of the H-I rocket. After launch, the satellite was renamed Ajisai , but it is most commonly known by the acronym EGP... )	LEO Low Earth orbit A low Earth orbit is generally defined as an orbit within the locus extending from the Earth’s surface up to an altitude of 2,000 km...	9 SRMs, 2 stages
27 August 1987, 09:20	17(F)	ETS-5 (Kiku-5)	GTO	>-	19 February 1988, 10:05	18(F)	CS-3A (Sakura-3A)	GTO	9 SRMs, 3 stages
16 September 1988, 09:59	19(F)	CS-3B (Sakura-3B)	GTO	9 SRMs, 3 stages
5 September 1989, 18:11	20(F)	GMS-4 (Himawari-4)	GTO	6 SRMs, 3 stages
7 February 1990, 01:33	21(F)	MOS-1B (Momo-1B)	LEO Low Earth orbit A low Earth orbit is generally defined as an orbit within the locus extending from the Earth’s surface up to an altitude of 2,000 km...	>-	28 August 1990, 09:05	22(F)	BS-3A (Yuri-3A)	GTO	>-	25 August 1991, 08:40	23(F)	BS-3B (Yuri-3B)	GTO	>-	11 February 1992, 01:50	24(F)	JERS-1 (FUYO-1)	LEO Low Earth orbit A low Earth orbit is generally defined as an orbit within the locus extending from the Earth’s surface up to an altitude of 2,000 km...	9 SRMs, 2 stages