Multiple UV mapping problem i'm new to blender.
I'm a bit confused on the concept of multiple uv mapping.

My workflow:
I made an object, a plane, and I wanted to assigned different materials and UV maps for the cockpit and the body.


I made the seam
Assigned each materials to its corresponding part (the cockpit and body)
Unwrapped the cockpit
Create new uv map
Unwrapped the body


but as I select all, the uv map on the "body" still consist of the body itself and the cockpit

Then when I added texture and using the body and the texture overlapped.

What i want is different uv map and different image texture for each part.
Please help I've been stucked with this problem for 3 days..    

Update
I've tried to separate the object, made its own uv maps for the body and the cockpit, and I joined them again. But then each uv map only show the texture assigned to it and not both applied/showed in object mode/texture paint

and when I exported it to obj file and open it on papercraft program, the texture shown is the uv map that set as active for rendering
Example : we have a plane and want to 3 materials based on two textures.

Plane parts :


The cockpit : glossy material with texture 1
The nose : diffuse material also with texture 1
The other parts : diffuse material with texture 2





Create your plane
Add the three materials
In edit mode, select the wanted faces and assign them to the corresponding material





Create your UV seams (probably corresponding to the material). You may also have done the seams before the material assignation





Select the wanted parts using the "select" button of the material,
Then UV unwrap





The materials can be defined as you wish (here I used a bake to produce the textures
You can also export the UV map parts separately in order to paint over it in the tool you want (or paint directly here in Blender)