Lecture 7 Flashcards
What is weathercock stability
yaw stability
What part of the plane has the main contribution to static directional stability?
Size and arm of vertical tail
What is static directional stability?
Ability of a plane to resist slipping
To yaw right what direction does the rudder need to turn
right
Condition of static directional stability
dCn/db >0 and at b=0 Cn=0 | Cn yawing moment coefficient b sideslip angle
When is side slip angle positive
When the wind is coming from the right “wind in right ear”
Which axis is lateral stability
roll
Definition of lateral static stability
Ability of aircraft to recover from a disturbance about the roll axis
Definition of Dihedral angle
The angle the wings are tilted by
How do High wings create lateral stability?
Move the CoG higher up
Out of high wings and low wings which are more likely to be dihedral
low wings
Pros of High wings [2]
Good for loading aircraft, protects engines from damage
Cons of high wings[2]
Increased drag near wing box, landing gear integration is difficult
Conditions for static lateral stability
maths
dcl/db<0 [negative gradient] and when cl=0 b=0
How does sweep contribute to lateral stability, and another pro
effective span shortens when sideslipping, good at transonic speeds
