H3 (rocket)

H3

Launch of a H3 rocket carrying the QZS-6 satellite on 2 February 2025
Function	Medium-lift launch vehicle
Manufacturer	Mitsubishi Heavy Industries
Country of origin	Japan
Cost per launch	US$50 million for H3‑30S[1]
Size
Height	63 m (207 ft)[2]
Diameter	5.27 m (17.3 ft)[2]
Mass	574,000 kg (1,265,000 lb) for H3‑24L[3]
Stages	2
Capacity
Payload to SSO
Mass	4,000 kg (8,800 lb) for H3‑30[2]
Payload to GTO
Mass	4,000–7,900 kg (8,800–17,400 lb) for H3‑24[2][4]
Associated rockets
Family	H-II family
Based on	H-IIB
Launch history
Status	Active
Launch sites	Tanegashima, LA-Y2
Total launches	5
Success(es)	4
Failure(s)	1
First flight	7 March 2023
Last flight	2 February 2025
Carries passengers or cargo	ALOS-4
Boosters – SRB-3
No. boosters	0, 2 or 4
Maximum thrust	2,158 kN (485,000 lbf) each[3]
Total thrust	4,316 or 8,632 kN (970,000 or 1,941,000 lbf)
Specific impulse	283.6 s (2.781 km/s)
Burn time	105 seconds
First stage
Powered by	2 or 3 × LE-9
Maximum thrust	2,944 or 4,416 kN (662,000 or 993,000 lbf)[3]
Specific impulse	425 s (4.17 km/s)
Propellant	LOX / LH2
Second stage
Powered by	1 × LE-5B-3[3]
Maximum thrust	137 kN (31,000 lbf)
Specific impulse	448 s (4.39 km/s)
Propellant	LOX / LH2
[edit on Wikidata]

The H3 rocket is a Japanese expendable launch system. H3 launch vehicles are liquid-propellant rockets with strap-on solid rocket boosters and are launched from Tanegashima Space Center in Japan. Mitsubishi Heavy Industries (MHI) and JAXA are responsible for the design, manufacture, and operation of the H3. The H3 is the world's first rocket to use an expander bleed cycle for the first stage engine.^[5]

As of July 2015^[update], the minimum configuration is to carry a payload of up to 4,000 kg (8,800 lb) into Sun-synchronous orbit (SSO) for about 5 billion yen, and the maximum configuration is to carry more than 6,500 kg (14,300 lb) into geostationary transfer orbit (GTO).^[2] The H3‑24 variant will deliver more than 6,000 kg (13,000 lb) of payload to lunar transfer orbit (TLI) and 8,800 kg (19,400 lb) of payload to geostationary transfer orbit (GTO)(∆V=1830 m/s).