SRB-A

SRB-A / SRB-3
Closeup of the SRB-A attached to the H-IIA rocket which launched the Global Precipitation Measurement spacecraft
ManufacturerIHI Corporation
Country of originJapan
Used on
SRB-A
Height14.6 m (47 ft 11 in)
Diameter2.5 m (8 ft 2 in)
Gross mass75.5 t (166,449 lb)
Propellant mass66.8 t (147,269 lb)
Maximum thrust2,300 kN (517,061 lbf)
Specific impulse283.6 s (2.781 km/s)
Burn time110 seconds
SRB-3
Height15.1 m (49 ft 6 in)
Diameter2.5 m (8 ft 2 in)
Gross mass76.6 t (168,874 lb)
Propellant mass66 t (145,505 lb)
Maximum thrust2,158 kN (485,138 lbf)
Specific impulse283.6 s (2.781 km/s)
Burn time116 seconds

The SRB-A and SRB-3 are a family of Japanese solid-fueled rocket boosters developed and manufactured by IHI Corporation for use on the H-IIA, H-IIB, Epsilon, H3, and Epsilon S launch vehicles. The earlier versions, designated SRB-A, flew from 2001 to 2025, while the successor SRB-3 made its first flight in 2023.