ICBMs are commonly launched from below ground. How much fuel could be saved if a missile is launched below ground instead of above? If the tube was deeper with modified launch by a separate chemical launch mechanism to create a back pressure and take to pressureon a piston not to destroy the rocket but lift the rocket to achieveachieving much of the velocity to achieve orbit be more efficient? This way rockets of many sizes could use the extra push and may be a reusable first stage launch.
This piston is powered by rockets that are efficient whilst in compression. The lift is created by pressure build up like in internal combustion chamber with a constant burn not from rocketing out. The maximum Gs up and out. What prevents the use of electric engines to assist with spacecraft launches? (Launch Booster Supplement)
https://metro.co.uk/2018/03/30/russia-tests-4000mph-hypersonic-missile-near-impossible-to-shoot-down-7428694/
What is the deepest we have ever gone into the Earth?
Bonus questions: Will a 3 dimensional magnetic bearing rail set up be strong enough to keep the ship or piston from coming in contact with the rail/wall? Would composing the ship of graphite and bismuth keep it center? Will there be a static charge and how to absorb it?