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Tangentional force on missle

  1. Jun 2, 2012 #1

    Im currently looking at ballistic missile curves and how to determin impact locations.

    I found an article discussing this.

    According to the article several accelerations act on the missile, including two I can't figure out.

    These are called "propulsive acceleration" and "tangential acceleration of the launch site"

    Can someone explain why these are not the same? or what they represent?
  2. jcsd
  3. Jun 2, 2012 #2


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    My guess: "propulsive acceleration" accounts for the issue that the propulsion might be a bit asymmetric.
    "tangential acceleration of the launch site" would be an acceleration of the device due to recoil or other forces.
  4. Jun 2, 2012 #3


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    This seems to explain one of your questions:

    “A company called Sea Launch Corporation launched its first satellite into orbit on Sunday. The company launches rockets from a converted offshore oil platform which can be moved to a location on the equator. Why do they launch from the equator?
    Because the earth is spinning, every point on the surface has a tangential speed proportional to its distance from the earth's axis. Rocket launchers can take advantage of this tangential speed to give their rockets a head start on their journey into orbit, and the greatest tangential speed is obtained at locations furthest from the earth's axis, i.e. on the equator.”

  5. Jun 2, 2012 #4


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    judging from equations (1) and (13) of http://faculty.kfupm.edu.sa/ae/aymanma/images/Ballistic%20missile%20trajectory%20prediction%20using%20a%20state%20transition%20matrix.pdf [Broken],

    i think "propulsive acceleration" means the onboard rockets

    and "tangential acceleration" seems to mean centripetal acceleration of the launch site :confused:

    but the tangential acceleration is zero :wink:
    Last edited by a moderator: May 6, 2017
  6. Jun 5, 2012 #5
    [STRIKE]The tangential acceleration is also nonzero, because the tangential velocity, though constant in magnitude, is changing direction.[/STRIKE] Oh, wait, I see what you mean. Yes the earth is not increasing or decreasing its rotation speed appreciably!. Though, if we want to take a larger view - i.e. we are launching a satellite beyond Earth orbit into the larger solar system, or beyond, then we should consider the velocity of the earth and of the sun :)
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