Italian engineer Secondo Campini was among the first people in the aircraft industry to realize the potential of jet propulsion. As early as 1932, he built a jet-powered boat to prove the concept and get support from the Italian authorities. Once he got the Air Ministry interested, Campini started developing a jet airplane with the help of Caproni aircraft company. By the late 1930s he seemed to be on the path to making the world’s first jet-propelled aircraft.
Combining piston and jet propulsion
To power his experimental aircraft Campini used a type of engine known as motorjet, which he also called thermojet. It used a conventional piston engine’s power to drive a three-stage air compressor instead of a propeller. The compressed air then flowed into a combustion chamber, where it was mixed with fuel and ignited. The engine also featured a rudimentary form of afterburner, as additional fuel could be added into the tailpipe to increase thrust.
This propulsion system using a 900-hp Isotta Fraschini liquid-cooled radial piston engine was fitted into an all-duralumin fuselage ahead of a two-seat cockpit. The wing was mounted as low as possible, while the cockpit as high as possible, to provide the most of straight airflow to the deeply buried engine.
Testing the N.1
The Caproni Campini N.1 performed its maiden flight on August 27, 1940, at a Caproni facility in Taliedo near Milan. While the N.1 was certainly seen as a breakthrough aircraft pioneering a new propulsion principle, the design proved to be very raw and displayed very poor performance. Its top speed stood at mere 233 mph, which was lower than that of most contemporary fighter aircraft. Even the use of the afterburner only added a couple dozen miles per hour of speed, while hugely raising the fuel consumption. Another nuisance was that the N.1’s motorjet produced so much heat that the pilot had to keep the canopy open during the flight in order not to be baked alive.
In April 1941, a second prototype flew. It also performed a fly-past over Rome later in the year. The Italian leadership was very proud of the achievement and the N.1 bathed in publicity despite its meager performance.
The work on the N.1 continued well into 1943, but after the Allies landed in Sicily and began advancing northward, Italy’s resources for active research into jet technology dwindled. Thus, despite being among jet aviation pioneers at the start of the race, Italy soon lost its positions in that sphere for good. On the other hand, Campini’s motorjet was a technological dead-end anyway. It became evident very soon that the future of jet aircraft belonged to true turbojets, not piston engine hybrids.
When the Caproni Campini N.1 made its first flight in August 1940, its creators thought they had just launched the first jet in history. However, exactly one year earlier, on August 27, 1939, Germans flew their Heinkel He 178. Besides being the actual first aircraft to fly using jet propulsion, the He 178 also featured a true turbojet engine. The N.1 was, thus, actually the number two rather than number one.
However, at the time Germany did not make that achievement public. Moreover, it kept the breakthrough innovation secret even from its closest ally, Italy. It was only later in the war that Germany provided its turbojet technology for another Italian jet design, the Reggiane Re.2007. However, conceived too late, this concept never materialized into even a prototype.
One of the two flying prototypes of Caproni-Campini N.1 has been preserved and is now on display at the Italian Air Force Museum at Vigna di Valle, near Rome.