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Science Forum

  1. 19 Feb '17 20:15
    YouTube

    Second first stage landing of the year.

    I am looking forward to the first reuse, and the falcon heavy which will have three first stages all at once!

    If they get into the swing of things with at least one reuse on average this year, then by next year the cost of spaceflight will have almost halved!
  2. Standard member sonhouse
    Fast and Curious
    20 Feb '17 17:07
    Originally posted by twhitehead
    [youtube]glEvogjdEVY[/youtube]

    Second first stage landing of the year.

    I am looking forward to the first reuse, and the falcon heavy which will have three first stages all at once!

    If they get into the swing of things with at least one reuse on average this year, then by next year the cost of spaceflight will have almost halved!
    Great news indeed. So I wonder why NASA didn't think of this say, 40 years ago?
  3. 20 Feb '17 20:30
    Originally posted by sonhouse
    Great news indeed. So I wonder why NASA didn't think of this say, 40 years ago?
    They did. Its called the space shuttle.

    The problem was, the idea started out well, but then got ruined by requirements. For example the military required it to have a very large cargo bay. But overall, the space shuttle was quite successful - just very very costly. Although it was reusable, servicing it for each flight cost more than building a new falcon 9.

    Another factor might be computers, but I don't think so. I think computers from the 80's were probably sufficient to land a falcon 9.

    SpaceX built the falcon rockets from the very beginning with re usability in mind. They spent extra on the rocket design to make it reusable, and carry extra fuel for the return journey which results in smaller payloads for the rocket size. But the planning and investment is paying off.
  4. 20 Feb '17 20:34
    Originally posted by sonhouse
    Great news indeed. So I wonder why NASA didn't think of this say, 40 years ago?
    I must also add that the concept of landing the first stage has been considered many times but discarded as infeasible.

    https://en.wikipedia.org/wiki/Reusable_launch_system

    Wikipedia suggest that advances in rocket technology and materials is partly responsible for making it possible.
  5. 20 Feb '17 20:38
    Here is an interesting concept:

    https://en.wikipedia.org/wiki/Adeline_(rocket_stage)

    Fly back just the engines.
  6. Standard member sonhouse
    Fast and Curious
    21 Feb '17 13:48
    Originally posted by twhitehead
    Here is an interesting concept:

    https://en.wikipedia.org/wiki/Adeline_(rocket_stage)

    Fly back just the engines.
    Looks like it would take more hardware than just flying the rocket backwards.
  7. 21 Feb '17 15:05
    Originally posted by sonhouse
    Looks like it would take more hardware than just flying the rocket backwards.
    The Adeline idea is to put wings on the engine and fly it like a plane back to a landing spot. The engines are the most expensive part of a rocket.

    My guess is that wings means two things:
    1. lower fuel requirements than the spaceX method.
    2. more flexibility on landing location (currently spaceX must land at sea for some types of launch).