A branch drain accepting waste products delivered to it vertically, by gravity, from one or more similar but usually smaller fixtures, and conducting them horizontally to the primary disposal drain.
But this preliminary document is the clearest indication of the Pentagon's thinking about the future of nuclear missiles. In short, the Pentagon plans to replace the Minuteman III ICBM with a new launch rocket, one that would launch from the same silos in Montana and South Dakota where the missiles sit now. However, a new missile does not mean a new warhead.
The first successful test followed on 21 August 1957; the R-7 flew over 6,000 km (3,700 mi) and became the world's first ICBM. The first strategic-missile unit became operational on 9 February 1959 at Plesetsk in north-west Russia.