Gaetano Crocco
Gaetano Arturo Crocco (26 October 1877 – 19 January 1968) was an Italian scientist and aeronautics pioneer, the founder of the Italian Rocket Society, and went on to become Italy's leading space scientist. He was born in Naples.
In 1927, Crocco begun working with solid-propellant rockets and, in 1929, designed and built the first liquid-propellant rocket motors in Italy. He began work with monopropellants (fuel and oxidizer combined in one chemical liquid) in 1932, making him one of the first researchers in this field.
As head of the School of Aeronautics of the University of Rome, he performed research on flight mechanics, structural design, and high-altitude flight in addition to his work in rocket propulsion.
Because of his early efforts in aeronautics, Italian satellites were launched starting in the 1960s. The San Marco programme was a cooperative effort of NASA and the Italian Space Commission, with NASA providing launch vehicles, use of its facilities, and training of Italian personnel.[1]
Aeronautical space activities
G.A. Crocco is a pioner both in aeronautics and astronautics. In 1898 he was serving in the Italian Army Engineers Corps in the Wireless Dept. when he met Captain Maurizio Moris. Moris, heading a Specialists Brigade, was deeply interested in the new field of aeronautics: he took Crocco in his staff starting a lifelong cooperation. At the time the Specialists Brigade was testing anchored balloons on the Bracciano Lake, north of Rome. Since 1904 Crocco started experimenting with airships. In 1906, together with Ottavio Ricaldoni he developed Airship 1 featuring a revolutionary semi-rigid flexible structure. On October 31, 1908, piloting an improved version of the airship, the N1, supplied 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. N1 was the first airship ever to fly over Rome at an attitude of 500 mt (1500 ft). In 1912 Crocco and Rinaldoni tested an 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 the meantime Crocco kept studying propellers’ shapes and sections and in 1914 drew plans for a closed-circuit wind tunnel to be built in Rome. In 1923 Crocco started studying space flight, jet propulsion and rocket fuels. In 1927 the Aeronautic Experimental Institute where Crocco was working, obtained a 200,000 ItL financing (equivalent to today’s 1million Euro) to develop black-powder-fuelled rockets to be tested later in a BPD firing range at Segni, east of Rome. He moved onto research on liquid fuels, drawing plans for the first Italian-built combustion chamber, tested in 1930 with the help of his son, Luigi Crocco. The outbreak of WWii 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. In those years Crocco wrote hundreds of papers and patented so many inventions that his students used to say in mock poetry "Everything I use or see, Oh my Crocco is made by thee."
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. In the inaugural speech he spoke extensively on man-made satellites and rocket trajectories. In 1951 he founded the Italian Rocket Association (AIR) to rally all the fans of the new astronautic science. In 1951, a full decade before the Gagarin space flight, he held a meeting on the problems of a manned spaceship re-entry in the atmosphere. Later on he devised a parallel-stages vector, a futuristic solution as compared to superimposed stages. In 1956 Crocco, more than 80 years old, produced what is considered his most important contribution to world 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. The importance of his intuition, now a scientific theory known as ‘gravitational slingshot’ or ‘gravity assist’ or ‘swing-by’, was such that the NASA recommended the study of his theories and especially the swing-by maneuvers suggested by Crocco to all the contracting firms working on interplanetary flight and its perspectives.
The ‘Crocco Mission’ or ‘Crocco Grand Tour’
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. Then another 425 days should elapse on the Red Planet to re-align the planets so as to travel back again in 259 days. Crocco deemed this period too long and drew his own calculations exploiting Mars gravity pull to fly over the planet without landing. Mars gravity would deflect the spaceship’s trajectory towards the Earth cutting the flight’s overall length to less than a year, the only objection being the poor quality of data gathered passing over Mars at an altitude of more than a million miles. But, Crocco added, should the spaceship be re-directed towards Venus and not the Earth, it would fly over Mars at a very closer range: observation by the astronauts would be much more satisfactory, and moreover they could observe Venus as well, still keeping the trip’s time under a year. He calculated 113 days from Earth to Mars, 154 to reach Venus from Mars and 98 days from Venus back to Earth and affirmed that the first occasion for this ‘Crocco Grand Tour’ would be occurring in 1971. Gravity assist manoeuvres as envisaged by him are used extensively in all interplanetary missions today.
Bibliography
- Museo di Vigna di Valle
- Gaetano Arturo Crocco, Giro esplorativo di un anno Terra-Marte-Venere-Terra, Rendiconti del VII Congresso Internazionale Astronautico, Roma, settembre 1956, pagg. 201-225; traduzione inglese: "One-Year Exploration-Trip Earth-Mars-Venus-Earth," Gaetano A. Crocco, c, Rendiconti pp. 227–252.
- Filippo Graziani, La Scuola di Ingegneria Aerospaziale nell’ottantesimo anniversario della sua fondazione