hello everyone!

i got my c-130 normal (i mean without any expension)
and some times when i switch views with the "s" button or any button the engine sound is making like bumping and the watches of the engines are go all the way to the back and come back after moment.

this is really annoying as my computer is already fly with the c-130 in like 20 fps.

any one know this problem?
cheers