Add local rotation smoothly?

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320016-cube.gif

How could i add local rotation smoothly?

Sorry that was bad. So i want it to turn smoothly from its current location to new in specific time. Just like finterp to, but with local rotation.

It’s the GIF that’s choppy, not the animation.

If you want it in a specific time, use a timeline:

Thats not what im looking for. It does exatcly that yeah, but i want animation to be smooth like in fighter jet when it turns. How could i do that?