2 solid rocket boosters along with the 3 main engines help this craft, such as the Atlantis, go 3,000 mph
They were ignited after the three Space Shuttle Main Engines' thrust 
level ... largest solid-propellant motors ever flown and the first of such large 
rockets... [DOC] [TLE] Space Shuttle [PAR] The idea of a reusable "space shuttle" that could launch like a rocket but ... Four 
shuttles were made (Columbia, Discovery, Atlantis, Challenger).