In the past, I have had people as why the mCP-X starts and stops abruptly. This is what is known as "cogging" and it's caused by the magnets inside the main motor against the stater. This is completely normal and I assure you, there is nothing wrong with your helicopter. It just needs these strong magnets to produce the power needed to put this helicopter in the air and allow it to do what it was designed to do.

As always, if you have any questions, comments or suggestions, post them below in the comment section.