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Aerospace Weird aerospace question to probably be corrected

  1. Jun 12, 2017 #1
    This probably is as impossible as i think, but can an airplane have slanted wings? By this I mean, can an airplane's wings operate like a see-saw with one with angling upward, and the other going equally downward while the main body of the plane doesn't move at all. This mechanism would sort of be like you held your arms out sideways and tilted one up and one down, like you were childishly pretending to be an air plane.
     
  2. jcsd
  3. Jun 12, 2017 #2
    It could be done. But it would serve no purpose.

    If you hung the fuselage of the plane with a hinge to high wings, you could then operate the ailerons to cause the wings to bank left and right while the fuselage remained upright. You would also need to apply opposite rudder to keep the plane from actually turning. You would need to do some very careful planning and designing to keep the thing from stalling.
     
  4. Jun 12, 2017 #3

    JBA

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    If you used the rudder to defeat the turn this is the method used to "Slip" a plane to a lower altitude to prevent overshooting a landing point and results in the plane effectively sliding sideways down the slope of the wings. In that case, the plane is turned turned so that the combination of the slip vector and forward power vector results in a final slip vector that is directly toward the runway. The slip maneuver is a standard part of pilot training and in my case was practiced by climbing to an altitude of 2000 ft, finding a long straight (rural) road and slipping the plane down to the minimum allowable altitude of 800 ft along the path of that road, then climb back to 2000 feet and repeat.
     
  5. Jun 13, 2017 #4

    CWatters

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    The Wright Flyer used wing warping instead of separate ailerons. I read somewhere there is an F-18 that has been modified to do the same.

    PS. You can reduce the adverse yaw effect by twisting the down going wing more than the up going to balance the changing drag.
     
  6. Jun 13, 2017 #5

    CWatters

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    Oh wait I misunderstood the OP. He effectively means lateral weight shifting like a hang glider.
     
  7. Jun 13, 2017 #6
    But he said "while the main body doesn't move at all". I don't think he's thinking hang glider. More specifically, I don't think he's intending to turn the plane while the wings are in a bank.
     
  8. Jun 13, 2017 #7

    1oldman2

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    That must be this one.
    https://www.nasa.gov/news/highlights/aeroelastic_wing.html
    "A research jet with a curious link to the Wright Flyer flew to Oshkosh, Wis., July 28 to join the world's largest aviation event. The people and aircraft gathered at the Experimental Aircraft Association's AirVenture 2003 this week to celebrate a century of flight include a special NASA F/A-18 with the ability to twist its wings to cause the airplane to roll. That's a new twist on a very old theme -- wing warping -- exploited by Wilbur and Orville Wright."
     
  9. Jun 13, 2017 #8

    CWatters

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    That would be difficult to arrange due to the large surface area of the wing and Newtons third law.

    I suppose it could be done but it's rather pointless and would be uncomfortable for passengers to remain uptight in turns.
     
  10. Jun 13, 2017 #9
    It would clearly be pointless. With the hinge setup I described, Newton's third law has very little to do with it. The wings would be repositioned with the ailerons. Keeping the thing from turning would be a trick. The rudders would have to be fixed to the wing structure. The fuselage could still hold the elevators. Other than that, it would just hang in there for the ride.
    But not with me on board.
     
  11. Jun 15, 2017 #10

    Baluncore

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    Welcome to PF.
    Flying in a straight line with one wing high is inefficient because the airflow over the wing profile becomes diagonal. There is then a difference to the induced drag at the opposite wing tips, which will tend to level the wings to make the attitude more stable and the wings more efficient.

    When changing direction an aircraft banks so as to keep the lift and airflow over the wings stable. The apparent 'gravity' forces experienced by both the wings and by the people in the fuselage require the same angle of bank for the wings and for the fuselage. If there was a hinge, the fuselage should always hang perpendicular to the wings, so the hinge would be redundant.

    So there is no advantage in a hinge between the wings and fuselage. It would result in inefficient or dangerous airflow over the wings, and/or dangerous sideways forces on the passengers.

    @octo3, have the posts so far answered your question?
     
  12. Jun 16, 2017 #11

    Nidum

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    More interesting and certainly more practical is the idea of variable sweep wings .

    Variable sweep wings are often just called swing wings .

    Variable sweep is one of several methods for providing variable geometry wings . There are follow on links listed in the Wikipedia article that lead to information about other methods of providing variable geometry and to information about some actual aircraft using these types of wing design .

    The actual swing wing concept is a technology that has historically provided an excellent way to get maximum performance for aircraft which have to fly under a wide range of different conditions . In recent time however other variable geometry wing technologies , astable aircraft designs , fly by wire and sophisticated rapid response computer flight control systems have largely made the swing wing concept obsolete .
     
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