S-Series (rocket family)

S-Series is a fleet of sounding rockets funded by the Japan Aerospace Exploration Agency (JAXA) that have been in service since the late 1960s. Manufactured by IHI Aerospace and operated by the Institute of Space and Astronautical Science (ISAS). The nomenclature of the S-Series rockets is the number of "S"s indicates the number of stages, and the following number details the diameter of the craft in millimeters. For example, the S-310 is a single stage rocket with a diameter of 310 mm.

On January 14, 2017, the SS-520-4 rocket (modified sounding rocket) attempted to become the lightest and smallest launch vehicle to send a payload to orbit,^[1] however, the rocket failed to reach orbit.^[2] A second attempt was made on February 3, 2018. This time, the rocket reached orbit and successfully deployed TRICOM-1R (Tasuki), a 3U CubeSat.^[3] Its 2018 launch made it the smallest orbital rocket both in mass and height.^[4]

A retired single stage Japanese sounding rocket. The S-160 had a maximum flight altitude of 80 kilometers, a launch mass of 100 kg, a diameter of 160 mm and a length of 4 meters. It was launched 13 times between 1965 and 1972.

A retired single-stage sounding rocket developed by the Institute of Space and Aeronautical Science of the University of Tokyo, predecessor of the Institute of Space and Astronautical Science (ISAS), to study the ionosphere. A variant S-210JA was launched from Japan's Antarctic base.^[5] The first S-210 launch took place in 1966, and was retired in 1982. The first two launches of the full sized versions in took place between 1966 and 1967: they were both failures, with the motor case burning through. After redesign of the case and improved quality control the subsequent launch in August 1969 was successful. Following further successful tests in Japan in 1970–1971, the rocket was cleared for intensive use at the Japanese Antarctic base at Syowa in 1972–1978.^[6]

The S-210, like other rockets in the series, used a solid rocket motor. The propellant grain of the motor included Hydroxyl-terminated polybutadiene (HTPB) binder, making it better suited for the cold temperatures of the Antarctic launch site.^[7]

• Gross mass: 300 kg (660 lb)
• Height: 5.20 m (17.1 ft)
• Diameter: 0.21 m (0.69 ft)
• Apogee: 110 km (68 mi)

It was built to replace the smaller S-160 rocket which was a proof-of-concept design rocket.

The S-310 is an active single-stage sounding rocket. Like its predecessor the S-210 it was developed for observations in Antarctica. The rocket is 310 mm in diameter, and can reach an altitude of 150 km.^[8] The first flight of S-310 in January 1975 was successful, and it has been launched at Kagoshima Space Center at Uchinoura, Showa Station in Antarctica and Andøya in Norway. As of January 10, 2020 the S-310 has completed 57 sub-orbital launches, with its most recent launch occurring on January 9, 2020.

• Gross mass: 700 kg (1,540 lb)
• Height: 6.80 m (22.30 ft)
• Diameter: 0.31 m (1.01 ft)
• Apogee: 190 km (110 mi)

El S-520 se desarrolló para reemplazar los cohetes sonda tipo K-9M y K-10. Es un cohete sonda activo de una sola etapa capaz de lanzar una  carga útil de 100 kg a más de 300  km y proporcionó más de cinco minutos de vuelo en microgravedad para experimentos. El primer lanzamiento tuvo lugar en 1980 y el más reciente fue el 11 de noviembre de 2024 (UTC). ^{[ 9 ]}

• Masa bruta: 2300  kg (5000  lb)
• Masa sin combustible: 400  kg (880  lb)
• Tiempo de combustión: 29 s
• Altura: 9,00  m (29,50  pies)
• Diámetro: 0,52  m (1,70  pies)
• Apogeo: 430  km (260  millas)

Esta versión es un cohete sonda de dos etapas o un cohete orbital de tres etapas , que utiliza el S-520 como primera etapa. A diferencia de los cohetes anteriores de la serie S, el SS-520 está diseñado para demostrar lo pequeño que puede ser un vehículo de lanzamiento orbital . ^{[ 10 ]}

Cuando se utiliza como cohete sonda suborbital, puede lanzar una carga útil de 140 kilogramos (310 lb) a una altitud de entre 800 y 1000 km. ^{[ 11 ]} Los dos primeros SS-520 se lanzaron en 1998 y 2000 respectivamente y transportaron con éxito sus cargas útiles en misiones suborbitales. ^{[ 12 ]}  

Tras un mayor desarrollo y la adición de una tercera etapa, la cuarta y la quinta versión del SS-520 fueron lanzadas en trayectorias orbitales completas.

• Masa bruta: 2.600  kg (5.700  lb)
• Altura: 9,70  m (31,80  pies)
• Diámetro: 0,52  m (1,70  pies)
• Apogeo: 1.000  km (600  millas)

• Cohete sonda (IHI Aerospace)