Gaetano Crocco

On 31 October 1908, piloting an improved version of the airship, the N1, with a rudder and direction indicators, Crocco flew from Vigna di Valle to Rome and back, covering 50 miles in one hour and a half.

In 1912 Crocco and Rinaldoni tested a hydroplane on the Bracciano lake while experimenting with airships together with other researchers (one of them, Umberto Nobile, would become eventually a famous polar explorer).

In 1927 the Aeronautic Experimental Institute where Crocco was working, obtained a 200,000 ItL financing (equivalent to today's 1 million Euro) to develop black powder rocket motors to be tested later in a BPD firing range at Segni, east of Rome.

The outbreak of World War II and lack of financing confined Crocco to academic activities: he directed the Aeronautic Engineering School from 1935 to 1942 and then again from 1948 to 1952, when Luigi Broglio succeeded him in the post.

After WW II Crocco went back to his old passions, missiles and astronautics, creating in 1950 an informative course on superior ballistics within the Aeronautic Engineering School.

[3] In 1956 Crocco, nearly 80 years old, produced what is considered his most important contribution to astronautics: in his "One-Year Exploration-Trip Earth-Mars-Venus-Earth" paper presented at the Seventh Congress of the International Astronautical Federation IAF, Rome, in 1956, he suggested exploiting the Mars and Venus gravitational fields as propelling forces to cut dramatically the travelling time of a space capsule.

This 'gravitational slingshot' or 'gravity assist' or 'swing-by' method was such that the NASA recommended the study of his theories and especially his swing-by maneuvers contracting firms working on interplanetary flight and its perspectives.

[citation needed] Basing his calculations on Hohmann's orbit, the sci-fi writer Arthur C. Clarke had stated once that an Earth to Mars flight with a minimum fuel consumption would require at least 259 days.