The Campini-Caproni Like a gun, which 'reacts' with a quick backward movement (i.e. the recoil) when a projectile is shot forward at high speed, a jet engine derives its thrust by reaction to its high-speed ejection of combustion products, and by the expansion of heated air, which is pushed out at a higher speed than when the air is drawn in. (After all, ordinary propellers work in a similar way. They accelerate backwards the air mass that moves through their rotating blades.) These introductory remarks are meant to help our visitors gain an insight into the workings of Ing. Campini's thermojet. It is, in effect, to be considered more as a hybrid than as a jet engine proper. An internal combustion engine characterized by reciprocating motion of pistons in its cylinder - in our case, a 900 hp Isotta Fraschini L. 121/R.C. 40 engine - drove a compressor incorporating 2 ducted propellers and a propeller designed to direct the flow and minimize the breakdown of the smooth airflow. A ring of injectors (i.e. the burners) introduced kerosine, whose combustion increased the volume of the thermojet and the exhaust velocity. It was an interesting application, albeit structurally different from German turbojets - like those fitted to the Messerschmitt Me 262 aircraft - which, in place of the reciprocating engine, featured a turbine-driven air compressor. The turbine was to be found past the blast chamber, and the air under pressure was heated not through the injectors, but through several blast chambers that heated the air by conduction. Which was a more effective solution. Eng. Secondo Campini started this project in 1930 and it was a revolutionary plane for the time using a new prop-less engine system. Campini patented the project in january 1931 but found no interest either in the military or the civilian market. Only in 1934 he finally convinced the Regia Aeronautica chiefs of the potential of the plane and two prototypes were ordered. Not having himself the capability of building the planes he joined the Caproni airplane factory and work finally started late 1934. It took a long time until the first one was completed, in the summer of 1940, finally being flown by Commander Mario De Bernardi on august 27th 1940. It was a complete success and the CC.1 (Campini Caproni #1) was the very first italian jet plane ever flown, just one year later the Heinkel 176, the german built very first jet plane ever. Test continued at Milano-Taliedo in 1940-41 and an important flight was the one on november 30th 1941. The CC.1 flew from Milan to Rome (475 km) setting a world record for having been the first jet plane to carry passengers (one) and mail. In the while the second prototype CC.2 had flown on august 31st 1941 and tests continued on both machines in 1942. In 1943 one was lost during a bombing run while the other survived the war and is at present stored, in perfect conditions, at the Italian Air Force musem at Vigna di Valle near Rome. More facts on the CC available here: http://www.museoscienza.org/english/aereo/caproni.html http://www.regiamarina.net/arsenals/planes_it/jet/jet_us.htm http://tanks45.tripod.com/Jets45/Histories/CC-2/CC-2.htm While turbojets usually consist of air intake, compressor, burning chamber, turbine, & exhaust, the CC motor-jet engine was physically subdivided into modules: air intake, compressor, piston engine, burners, & exhaust. The turbine section was switched to a more traditional piston-engine to act as a compressor. It was complex and heavy, with a poor thrust to weight ratio, but the modules and the ability to run as a kind of ducted-fan made for economical cruising. In fact the burners were not strictly needed as in a Jumo 004, and the plane could fly with them off. Campini motor-jet w/ 730kg thrust. Wing Span: 14.6 m; Length: 12.1 (12.9) m Maximum Speed: 375 km/h Cruise speed: 217 km/h T/O wt: 4200 kg Payload: 769 kg Total Production: 2 prototypes First flown: August 27, 1940