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 pressure not to destroy the rocket but lift the rocket to achieve much of the velocity to achieve orbit be more efficient? This way rockets of many sizes could use the extra push.

[![enter image description here][1]][1]


  [1]: https://i.sstatic.net/uvFII.jpg