For linear motion, after you've transferred some momentum internally and made the outer pipe move, the mass you moved has to stop, and when it does, it cancels out any momentum it gave the pipe to begin

get real now kallog.

it may take several minutes to equalize the pressures in the tank and pipe.

durring this process momentum is being transfered to the pipe giving it
linear acceleration and momentum thus the pipe moves in a linear direction
for a linear distance.

and continues to move in that direction.

any resistive forces that could apply are not stored up inside the pipe then
released when equalization occurs.

so the pipe is still moving , it has momentum , but is no longer accelerating
nor decelerating.

now you also can not decelerate the pipe by re-pumping the
air back into the tank.

because you would have equal and opposite reactions
occuring between the pump and the air tank.

but once youve compressed the tank again you can stop
the pipe by releasing the air in the opposite direction.

Although I do see your point that when you're immersed in one common set of knowledge it's hard to come up with new, different ideas. Most good new ideas come from young people who don't have such a long lifetime of the same old thing.

when you are trained to fail its hard to succede.

because you know you cant , youve been taught that
you cant , therefore no one else can either.

3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.