To set a boat in the water or send a rocket into space
[DOC] [TLE] setting in motion - Memidex dictionary/thesaurus [PAR] to cause to sit; place in or on a seat | to put (a fowl) on eggs to hatch them ; to put 
.... to send something out, such as a new ship into water or a rocket into space... [DOC] [TLE] rocket firing - Memidex dictionary/thesaurus [PAR] "rocket firing" definition: the launching of a rocket or missile under its own power.