Measuring distance on launch rail

Discussion in 'Ground Support' started by highflyer1968, Jul 11, 2019.

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  1. Jul 11, 2019 #1

    highflyer1968

    highflyer1968

    highflyer1968

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    Just wondering when setting up Rocsim for how long the rail is, do you just enter the length of the rail or from where the last rail button is? I have an 8 foot rail and the first button is about 75 inches from end of rail and second one is about 86 inches from the end.

    thanks for any help
     
  2. Jul 12, 2019 #2

    mbeels

    mbeels

    mbeels

    Putting the tree in rocketry

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    I would consider the length of the rail to be 75 inches, the rocket is only guided while both buttons are in the rail.
     
  3. Jul 12, 2019 #3

    manixFan

    manixFan

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    I think a lot of folks overlook this. I've seen tall rockets on 6' rails where the top button is only about 3' down the rail. Or sometimes the rail stop will be set a good foot or more up the rail which of course shortens the guidance. For my taller rockets I try to use an 8' rail whenever possible, especially if I know the launch speed is on the low side or if it's windy.

    That does raise a good question - in OpenRocket I don't need to add rail buttons to a rocket to sim it. So when it computes the speed off the top of the rail what actual distance is it using - the entire 6 or 8 feet? If so, it is overestimating the speed. Hmm.


    Tony
     
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  4. Jul 12, 2019 #4

    Banzai88

    Banzai88

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    You can change the effective length of the rail in OR as well.
     
  5. Jul 18, 2019 #5

    Buckeye

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