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astronautix.com Castor 120


Designer: Thiokol. Used on stages: Castor 120. Used on launch vehicles: Athena-1, Athena-2, Athena-3, Taurus. Gross Mass: 53,118 kg. Empty Mass: 4,086 kg. Propellants: Solid Thrust(vac): 168,000 kgf. Thrust(vac): 1,650.00 kN. Isp: 280 sec. Isp (sea level): 229 sec. Burn time: 81 sec. Diameter: 2.4 m. Length: 9.0 m. Chambers: 1. Chamber Pressure: 101.00 bar. Area Ratio: 24.00. Country: USA. Status: In Production. First Flight: 1994. Last Flight: 1999. Flown: 10.

A motor similar in size to the Peacekeeper missile stage 1 motor. It fills the gap between Castor 4A and the large segmented motors. Unit cost would be about $3.5 million for volume production, rising to $7.5 million for one annually. Further applications include using it as a strap-on for launchers, such as Delta. It can be used in a stage 1 or 2 strap-on since the forward and aft ends can take tension and compression forces. A (5.5 degree thrust vector control is provided by a movable nozzle. The grain can be changed (tailored) by adding aft slots to reduce thrust during maximum-q, and by adding forward slots for high initial thrust.. First Flight. November 1994. Propellant Type: TP-H1246 HTPB, 19% Al, and 69% AP. Propellant Shape: three machined aft conical slots with formed forward slot. Propellant Mass Fraction: 0.923 (49,032 kg). Burn Time: 81 sec.. Thrust: 1650 kN vacuum average. Isp: 280.1 sec vacuum. Itotal: 133,440 kNs vacuum. Pressure: 101 atm maximum and 78 atm average. Nozzle Throat Diameter: 368 mm. Nozzle Length: 1448 mm. Nozzle Exit Diameter: 1600 mm. Nozzle Materials: glass epoxy and polyisoprene flex bearing. 3D carbon-carbon throat. carbon phenolic exit cone. aluminum stationary shell. steel throat support. Casing Materials: carbon epoxy, lined with silica-filled EPDM rubber EPM.


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Last update 12 March 2001.
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