I'm trying to rig a plane that finishes in a loop.

I've already assign dependencies to simulate the tale's mouvement :

But I'm not finding the way to connect the bones that close the loop in order to separate the head mouvement from the tale :

For example: A mouvement dependency problem. I would like to be able to compress the head regardless of tale position, taking in account that the vertices indicated must be joined together:

I've tried parenting them, but it ends in strange formations or with the rest of the bones detached.

Is there a simple solution to achieve independence movements between the head and the tale?

[Updated] : Movement Storyboard :

Project blend file :