Concepts Abound As Launch Market Loosens

In Mojave, Calif., workers are cannibalizing a pair of surplus United Airlines Boeing 747-400 airliners for parts to build a flying launch pad.

In January their employer, Stratolaunch Systems, broke ground on an 88,000-sq.-ft. wing-fabrication facility that will be finished late this year. By mid-2013 it will be ...