The Cessna 500 series Citation I created the entry level light business jet market. Their success set the base for the world's largest family of corporate jets. Due to the early success of the Citation I, Cessna became the first of the big three American manufacturers which include Piper, Beech and Cessna.
In October of 1968, Cessna announced the beginning of the new model of jet powered business aircraft that would be capable of operating into airfields already served by light and medium twin turboprops. Named the Fanjet 500, the prototype flew for the first time on September 15th, 1969, and later named the Citation.
FAA certification was received on September 9th, 1971. A new and improved model of the Citation I was the 501 Citation I/SP, which is certified for single pilot operation. The I/SP started delivering in early 1977 and continued to 1985.