John Houbolt
John Cornelius Houbolt (born April 10, 1919 in Altoona, Iowa) is a retired aerospace engineer. He is generally credited with having effectively promoted the lunar mission mode called Lunar Orbit Rendezvous or LOR. This flight path was first endorsed by Wernher von Braun in June 1961 and was chosen for Apollo program in early 1962. This critical decision was viewed as vital to ensuring that Man reached the Moon in the 1960s, as President John F. Kennedy had proposed and, in the process, saved billions of dollars and time by efficiently using existing rocket technology.