Miguel Sánchez
PHOTOS OF RADIAL ENGINE: DAN CABRAL / PHOTOS TROSSI 1935: MUSEO NAZIONALE DELL'AUTOMOBILE TORINO
Factors such as aerodynamics, the rigidity of the chassis, the communicativeness of the steering or the distribution of weights are essential for a car to be well tuned. However, the truth is that without a good engine we are not going anywhere. It's like what Enzo Ferrari said: "When you buy one of my cars you buy the engine, the rest I give it to you". And well, once we are talking about engine types, we can do it for hours.
The bubbling of the American V8s, the enormous power of a V12, the good center of gravity of the boxers ... A world of mechanics applied to the four wheels where even the radial engines. Coming from aviation, specifically from the military, these devices receive their name from the fact that the cylinders are located radially with respect to the crankshaft.
Thus, everything is aimed at giving maximum power to the propeller. As a most obvious advantage, the radial motor has a great facility to be cooled by air due to its frontality. However, this very thing is the source of its biggest problems. In addition to being a poorly aerodynamic design, the ease of lowering its temperature can play tricks on it, causing cracks in the cylinders due to thermal shocks.
In short, it will be better to understand all this in the most visual way possible: with a video where you can see how each and every part of a radial engine is assembled.
AMERICA FOR DOMAIN OF THE SKIES
The First World War was a full stop in many things. Not only did he come out with a new map of Europe and its colonies marked by the irruption of the Bolshevik Revolution and the withdrawal of Germany, but also with the awareness that Humanity entered a new and dangerous era. The era of mass destruction. Suddenly, the old wars with soldiers shooting face to face were changed by the use of physics and chemistry against the civilian population.
Chemical weapons, artillery capable of firing from miles away, airplanes that turned the skies into a new battlefield. In fact, the role of the latter was so essential that armies like the North American the organization of their aviation was raised from top to bottom. Thus, it raised the need for several companies to replace rotary engines with more reliable ones with better cooling.
And it is that the rotaries had to constantly operate at maximum power. Outcome? A very short useful life, in which in addition a reliability was recorded as low as high was the number of pilots killed after stopping the engine in flight. With its good weight / power ratio -as it does not need a liquid cooling system-, radial engines quickly replaced rotaries. Something that was accelerated thanks to the fact that they easily solved the problem of heating thanks to their large front exposed to the wind.
RADIAL ENGINE BOOM AND FALL. FROM WHIRLWIND J-5 TO R2800
Around 1925 the US Navy began placing large orders for radial engines from Wright aeronautical. This made the company one of the largest motorization companies in the world, making the Whirlwind J-5 a star. Not surprisingly, it was the propellant for Charles Lindbergh's Spirit of Saint Louis when he crossed the Atlantic in 1927. A pioneering feat that was made possible, to a large extent, thanks to the reliability and low consumption of this radial engine.
Arrived at the prelude of World War II, the radial engine began to experience moments of anxiety. The reason lay in the aerodynamics: seeking better air penetration, both the RAF and the Luftwaffe relied on the narrow V-engines for the nose of their respective Spitfires and Messerschmitts. Anyway, this was not what gave the lace to our protagonists, but the massive application of reaction ones in the early 60s. Endowed with some heart-stopping powers, these beasts designed based on the four phases of the Brayton cycle ousted the already obsolete radial engines.
Today, there are only a few small recreational aviation companies that continue to manufacture them. An example of this is the Australian Rotec Aerosport, responsible for the R2800 model protagonist of the video we have seen before. A seven cylinders with electric ignition capable of delivering up to 110CV at 2450 rpm. All this if you can supply an average of 22 liters of gasoline per hour.
RADIAL ENGINE IN A CAR: FLYING ON THE GROUND WITH THE 1935 TROSSI
Putting an airplane engine on a car chassis is nothing new. After all, during the 20s and 30s this was quite common when creating mastodons to break top speed records. However, the normal thing was to place large V-shaped engines in front of the driver, never radial. And it is that, no matter how big a V-engine from a war fighter is ... More or less it can be placed throughout. But a radial with its huge front, how?
Well, although it may seem incredible to you, the engineer Augusto Mónaco managed to do it in 1935. And be careful, because the invention had such good results that it even competed in the Monza Grand Prix 1935 with Felice Trossi at the wheel. In addition, it must be recognized that this car is not so much one of the strange mechanical bizarre of the time but a vehicle with curious and thorough innovations.
Front-wheel drive first, saving a long drive shaft. Of course, its 16-cylinder two-stroke engine had to be a nightmare for the gasoline boy, as well as for mechanics unaccustomed to this ingenuity from the skies. However, the radial engine 1935 Trossi delivers 250CV at 6.000 rpm to move only 710 kilos. Anyway, we don't get a word other than "Ooh mama, what a bullet."
