What is the correct way to create and add components at runtime ?

I have a question, hope someone knows the answer, I create new (NewObject()) UStaticMeshComponents at runtime and place them in an TArray. They are registered and i can succesfully set a mesh and manipulate their placement right after creation. However, if i try to access the same TArray, which was declared in the header file, at another time, the array is empty… the meshes are still visible in the editor, but for some reason the TArray is empty? any clue??? tahnks a billion!