Rocket design
Our rockets

  • Antares Ia
  • Antares Ib
  • Castor Ia
  • Castor Ib
  • Castor IIa
  • Castor IIIa
  • Pollux Ia
  • Pollux Ib
  • Pollux Id
  • Pollux Ie
  • Pollux If
  • Pollux IIa
  • Urs Minor Ia
  • Urs Minor Ib
  • Urs Minor Ic
  • Urs Minor Id

  • Flight logs

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    Our water rockets

    Urs Minor is our smallest rocket with a pressure-vessel of 0.5 litres. The bottles are thin walled and therefore very light. The latest version uses a soft foam ball for recovery.

    Rockets of the type "Castor" and "Pollux" use solid, reusable bottles which can hold a pressure of more than 14 bar. Both rockets are equipped with a tennis ball for recovery.

    Antares consists of two solid 1.5 litre bottles with a Robinson coupling base to spout. The payload section is made of a thin walled bottle. The standard payload is the recovery system and an altimeter. There is some extra space for small experimental payloads. The FlyCam One 2 can be integrated on demand.

    To view a particular rocket click on one of the datasheets on the left.

    How do we name our rockets?

    Usually our rockets are named after stars or constellations. Each name is linked to a particular type of pressure-vessel. e.g. Castor stands for a one liter reusable bottle

    The number behind the name shows how many complete rockets of a type exist. "Castor II" indicates that we built two rockets of 1 liter reusable bottles.

    The letter is being incremented with each change of a rocket. This helps us to keep track of the changes and assign recorded flight data to a particular rocket design. Changes could be e.g. a new set of fins or, a different nose cone.
    "Castor IIa" indicates that we didn't change this rocket at all since its first launch. Sometimes a number or a letter is missing. In such a case we already started designing the next variant before the predecessor had its first launch.