The jet in light aviation: utopia forever or pathway of the future?

The jet is probably one of the greatest technical and scientific successes accomplished by the man and which equips today the majority of the commercial airplanes. Appearing at the end of the 1930s, jet propulsion quickly became a leading technology and its strengths have been demonstrated in many categories of aeronautics. Among them, commercial transport, military aviation or aerospace. Only one sector has not proved its compatibility with the jet engine ... at least not totally: light aviation. Through the history of jet aviation, we will see that light jets, or micro-jets (one to three seats on board) could hide a real commercial potential and form a market of the future in the coming years... The idea of ​​propelling an airplane by a jet engine is exposed as early as 1913. The transition to practice is however not possible at this time, because of the minimum speed to reach. In 1930, the English Frank Whittle filed the first patent of the reactor. From the beginning of the second world war, several nations embarked on the development of technology and in August 1939, the first real jet plane, the German HeinkelHe-178, took off for the first time. This is the beginning of the era of jet propulsion. Soon, the desire to develop more efficient aircraft and not to be technologically left behind by the enemy powers pushes the major Western nations to develop the technology and adapt it to operational aircraft. The conflicts following the Second World War will mark the advent of the jet engine: during the 1950s, jet fighters already clashed in the skies of Korea and soon, the propeller fighters were overwhelmed. The first civil jet airplanes appeared a few years later: De Havilland Comet, Boeing 707. The advantages of technology are no longer to be demonstrated: there are areas where the classic motorization (propeller) will not reappear, like long-haul commercial transportation. Naturally, many engineers and pilots wondered at the end of the second war on the issue of light aviation jet: big planes are equipped, so why not small? In France, several models came into being, such as the SIPA S200 Mini-jet (first flight in 1952), as part of state programs aimed at developing light aviation. Technologically too complex and with high operating costs compared to their piston counterparts, they did not go beyond the prototype stage. The pilots were essentially looking for the simplicity and comfort of flying with a well-developed engine, while the high performance of the jet was not one of their main concerns. Today, microreactors have two main areas of exploitation: - "experimental" light aviation: where light aircraft are equipped with very low power reactors (such as Subsonex). - Drones: many manufacturers of microreactors equip UAV designers, both military and civilian, like Microturbo, a leader in the field. At the last Paris Air Show, it was not surprising to meet many microreactors on the stands. Double-flow microreactors are even appearing in some engine manufacturers: in the south-west of France, one of them has recently developed a lightweight reactor designed to equip small passenger aircraft. The performances are on paper, but it lacks a commercial will, an impulse, a program that aims to develop this type of aircraft ... We can say that it is the skepticism linked to the past and the complexity of the aeronautical regulations that hinder this development. It is therefore a generation of young entrepreneurs that must act: to prove to the market that there is a place for these revolutionary aircraft is a challenge that will require a lot of motivation and enthusiasm, attributable to young people full of ambition.