Flight Basics

Mean Aerodynamic Chord  The distance between leading and trailing edge of the wing, measured parallel to the normal airflow over the wing, is known as the chord. If the leading edge and trailing edge of the wing are parallel then, chord is constant along the span. Most commercial or fighter aircrafts have swept or delta wings in which chord length is greater at the root than at the tip. Consequently, chord changes along the span of the wing. The average length of Chord is known as Mean Aerodynamic Chord.  It has a geometrical importance as CG should be located at certain point of the MAC in percentage of its length. So, the location of MAC is specific and it can be found out as: Locating MAC Measure the root and tip chord and draw following points on plane : At the root of the wing, draw a line parallel to the fuselage centerline extending forward from leading edge and rearward from the trailing edge. Both lines should be the length of tip chord. Do the same thing at the tip b...

  Wing twist is of two types named as geometric twist and aerodynamic twist:- Geometric Twist Different angles of attack at wing root and tip. Wash in Tip chord has a higher angle of attack than that of root chord. Wash out Angle of attack at tip is lower than that at wing root. It is useful in reducing tip vortices. Aerodynamic Twist Difference between zero-lift lines of airfoils at wing root and near the tip. Airfoils at root and near the tip have different zero lift angles of attack.

  Is your Aircraft stable? Let's see what defines stability for an aircraft over time. Stability Stability is the ability of an aircraft to encounter with the disturbances produced by turbulence, wind gust and flight control inputs to continue with a placid and safe motion. A stable aircraft is said to have equilibrium in flight. The stability of an aircraft is judged on the basis of two phenomena known as static an dynamic stability. Static Stability   Static stability is the initial tendency of an aircraft to return to its equilibrium position. Let's say if an aircraft is disturbed by a wind gust and tends to reach its previous equilibrium then, its said to be statically stable.    Dynamic Stability Dynamic stability is the time history of an aircraft's motion after it initially responds to static stability. Being statically stable doesn't guarantee an airplane the dynamic stability because   after reacting to the disturbance it might go away from the neutra...