Dynamic vs Static Stability

[Horia1337]

Hello guys i have a question for anyone that is able to give me a simple and easy to understand answear. Yes i will ask my instructor on next week at school but right now i am studying for my AIRAF which is coming really soon. Yes i know this is a CPL or even PPL problem but here i am never really understood how this thing work i am trying to undersand it today and i am having some big issues understanding how it works. Yes i have check my books and my online AIRAT course but i still cant undersand it well. So here we go.

I have seen a lot of questions on the AIRAF exams about static and dynamic stability. I Know that it can be static or dynamic, positive netural or negative. Where it gets me is:

If it oscillates with increasing amplitude it is statically stable but dynamically unstable.

I am having trouble understanding how it can be statically stable but dynamically unstable.
Thanks in advance for anyone that is able to explain this to me as if i were a 5 years old kid

[telex]

https://www.youtube.com/watch?v=mGG_LVO5Tis

[Horia1337]

The video is well explained but has nothing to do with my question. It talks about primary and secondary controls of the aircraft.

[telex]

The video is well explained but has nothing to do with my question. It talks about primary and secondary controls of the aircraft.

Can you state your question clearly and concisely? I'm sure it will help get an answer.

[photofly]

The diagrams on this page might be helpful:
https://www.boldmethod.com/learn-to-fly ... -aircraft/

i am never really understood how this thing work

You're not taught or expected to know how "it works". So don't worry about it.

[FL_CH]

> I am having trouble understanding how it can be statically stable but dynamically unstable.

Static Stability = "Does it want to return to where it was?"
Dynamic Stability = "Does it settle?"

Say you pitch the nose up and then release the back pressure from the control column. If the aircraft wants to lower the nose and thus "return to where it was" - it has positive static stability.

If, in trying to return to where it was, it goes past the original pitch into a nose-down attitude, then pitches up more rapidly, and then pitches down even more rapidly - it "does not want to settle" - it has negative dynamic stability.

[TWSC]

Previous post has it right, maybe try thinking about it as static stability refers to the stability at a given point in time, i.e. does the aircraft return to original position. Dynamic stability is the stability of the aircraft averaged over a longer period. If the oscillations average to 0, it is positive dynamic stability, but if the oscillations keep increasing it is a negative dynamic stability.
With static stability, positive=stable and it's the same thing with dynamic.