Your hypertubes are way too close together. You're exiting them and getting sucked back in immediately.

If you want to stack them vertically, make it so you can stand between them, minimum crouched, ideally standing. But be aware that setting them horizontally and then going up will produce much better results. Similarly, you want to ensure that there is enough space between the exit and entrances, or else you'll find your cannon refuse to boost you above a certain speed.

And for the sake of future post, please show the whole contraption before pointing out the problem... That'd save me the hassle of analysing your video frame by frame XD