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DRAG

 

                                                                               Drag

When an aircraft or any other body moves in atmosphere it experiences air resistance which retards its forward motion. This force is called drag. Drag occurs when an aircraft or any other object moves in air and it depends on the shape of the flying object.  Aircrafts and other flying objects are designed in such a manner to reduce the drag, which increases the efficiency of the aircraft.




Drag is experienced parallel to relative airflow. Drag is directly balanced by thrust produced by a propeller or an engine. Amount of thrust required to balance the drag depends of amount of drag, more thrust is required to balance a greater drag force produced.

If the drag produced by an aircraft is low then the aircraft consumes less fuel and operating costs are also low. The total drag acting on an aircraft includes

  • Profile drag                                       
  • Induced drag
  • Interference drag

Profile drag is further divided into

  • Form drag
  • Skin friction drag 



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