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    Flight day 2 - Castor Ia

    Date: 19.10.2008 (14:30 - 16:00)

    Weather conditions: sunny, warm, light winds

    After some improvements of the nozzle and the launcher we decided to do some launches just for fun. Of course there was another purpose: we were looking for a suitable launch site close to our new home. A spot near Hohenentringen looked promising. In addition we wanted to know how high a simple rocket can go with a pressure of approx. 10 bar.

    Five launches of Castor Ia were done.

    Launch 1: This was a good flight even though the nozzle started leaking just prior to launch at a pressure of 8 bar. Castor Ia went up in a slight arc, a bit towards the South. When it touched the ground a loud bang could be heard but no damage was done to the rocket. The flight duration was 8.3 seconds with 390 ml of water. The calculated hight was approx. 70 to 80 m.

    Launch 2 was done with the same parameters and the flight was similar.

    Launch site with almost unlimited space for returning rockets.

    Launcher version 1.1 with Gardena Standard Hose Connector.

    Launch 3: This time we filled Castor Ia with 600 ml water and pressurized it only to 4 bar in order to get a slow lift off. The rocket went up much slower and the footage was really nice. It went up in a slight arc and touched the  ground close to the camera where it made a big “jump”. This was the most beautiful flight of the day despite the relative low height.
    Flight duration was 5.5 seconds according to post flight analysis. The calculated hight was approx. 35 meters.

    Castor Ia before launch.

    Slow lift off with far too much water - just for the movie. The Air pulse occurs late.

    Launch 4:  At 8 bar a minor leak could be seen around the nozzle. But it was still possible to pressurize further to 10 bar. Castor Ia went up very straight to an even higher altitude than before. It was the highest flight of the day with a calculated height of approx. 110 m which is our all-time record! 
    Flight duration was 9.79 s with 390 ml of water and some dish liquid.


    Fast lift off with approx. 350 ml of water and a pressure of 10 bar.

    Launch 5 was similar to the first two launches and resulted in a similar height.

    When reviewing the videos of the launch pad camera it turned out that the curved trajectory of the first launches was due to slight misalignment of the launcher. The top section with the trigger mechanism was not fixed properly and moved when the pressure hose was pulled (during pressurization). 

    Lessons learned:
    Hohenentringen is a good place but requires a long walk. Getting there by car is not possible.
    Even the small rockets can go to an impressive height.