Airfraft Axis And The Wing Flashcards
What is the centre of gravity?
The average point through which the mass of the aircraft acts. The aircraft will pitch, roll and yaw about its CG.
What happens when the CG moves forward?
Become more nose heavy.
Tendancy to pitch down.
Stagnation point rises.
Upwash > downwash
What does platform mean?
Describes the top-down shape of the wing.
How do you find the taper ratio?
Tip chord / root chord
How do you find the aspect ratio?
Span / chord.
For swept wing, span^2 / chord.
What happens when you have a low aspect ratio wing?
Higher induced drag.
Stronger wing tip vortices.
What happens with a low taper ratio?
Prone to wing tip stall.
Increased lift.
How does aspect ratio affect Cl alpha graph?
High A.R means high Cl but low critical AOA.
Low A.R means low Cl but high critical AOA.
How does thickness affect the Cl, alpha graph?
20% thickness means higher Cl and higher critical AOA.
12% thickness means lower Cl and lower critical AOA
What the mean aerodynamic chord? (MAC)
the chord of an imaginary rectangular wing with similar longitudinal stability properties to the actual wing.
Position of CG and CP are give as a % of MAC.
0% at leasing edge, 100% at trailing edge.
What is the sweep angle?
Angle perpendicular of the fiesta large and the wing.
Long haul aircraft have larger sweep angles.
What is rigging angle?
Known as angle of incidence.
The angle between the aircraft’s longitudinal axis and wing chord.
The angle of incidence reduces from root to tip (washout).
What is dihedral angle.
Angle between the lateral axis below the wing and the upwards curve of the wing.
What is anhedral angle?
Angle between lateral axis above the wing and the downwards curve of the wing.
