What Makes an Aircraft Stable? | Stability & Control

Let's look at some of the different types of stability built into an aircraft, and how knowing about them will help answer some questions on the Private Pilot Knowledge Test.

[dean]

Great videos as always. As mentioned in previous post, the advantages and disadvantages of aft vs forward CG with the different types of stability would make a great video. I’ve been flying for 30 years and still learn/refresh from these videos. Remember, the day you stop learning is the day you stop flying.

[heefie]

This can be expanded upon as well. Aft CG will also lead to higher speeds due to less drag on the elevator

[aaronhammond]

But why though? - Due to the typically different angle of attack of the wing and horizontal stabiliser.
When the plane pitches up by eg 1deg, the main wing increases AoA from eg 4deg to 5deg, which is a 25% increase. The elevator though with lower starting angle of attack increases 1deg too, but from eg 1deg to 2deg - 100% increase!
Any small angle change disproportionately affects the stabiliser, which acts to undo the change.

Though, the starting condition that the wing is at a higher AoA then the stabiliser is true when the CoG is in front of the CoP, otherwise everything is reversed.

[RMGiroux]

Out of curiosity, what about the other 2 axes? Does dihedral help with roll stability? What would help yaw stability?

[ericrolerkite]

Off this topic but hoping I could get some clarity. On a O.D.P when it reads "Standard with minimum climb What does the standard refer to? Is it refering to what part your flying 91, 121, etc.

[ssssss]

AC is the same LC ? Or there is a difference between them

[phillipdelcore]

Longitudinal axis affects the roll not the pitch. Pitch rotates around the lateral axis

[mikearakelian]

Don't over egg thus stuff with a new student....most will drift away....