Tesla's Aircraft of the Future Page 5

mechanically or by wireless energy. By constructing appropriate objects, it will be possible to launch such a projectile into the air and release it almost exactly to a predetermined location, which may be 1000 miles away.

Thus, Tesla, many years before it appeared, described the weapon which today, unfortunately, does not provide strong arguments for peace, but rather, represents a great threat to its preservation.

Another article published in the New York Tribune titled "Interview with Tesla on the problem of flying at high altitudes to avoid air resistance." Tesla opposed the opinion of some authorities in the field of aviation, believing that piston airplanes would not be able to use great altitudes and the low air resistance that exists at those altitudes. (Which was later proven to be true). In one part of this interview, Tesla says:

“I doubt it will be possible to ascend to an altitude of 25-30 km, which is T. Mot's opinion. Firstly, I calculated that at an altitude of 30 km there is only 7 percent oxygen in the air, instead of 21 percent near the ground, and there will be great difficulty in supplying oxygen for fuel combustion, not to mention other problems. These difficulties are already known, and it was recently proposed to compress air with the help of a compressor and thus provide oxygen, and this plan, proposed by the Frenchman Rato, was already adopted in some machines. At altitudes of 30 km, a turbocompressor with no less than 10 stages would be needed, and its size would preclude its use.”

Flying at high altitudes undoubtedly has many advantages, but there are also performance limitations, and these will not be avoided until a radically new form of propulsion for flying machines and a new principle of fuel supply are found.

In 1921, Tesla first filed an application with the Patent Office in London for the registration of the invention "Method of Air Transport." The invention describes a new type of aircraft that is not a helicopter but can take off and land vertically, behaving like an ordinary airplane during horizontal flight. The application was rejected in 1922, but Tesla simultaneously filed the same application in America, which was not accepted until 1927 when it was expanded with the addition "Apparatus for Air Transport." Patent rights for "Method of Air Transport" and "Apparatus for Air Transport" were granted on January 3, 1928.

Tesla's aircraft is shown with two side views and one horizontal projection in figures 3 and 4. The structure consists of two wing surfaces, designated 1.1, which are rigidly joined and can form an almost perfect square for compactness and small size. A tail was not envisioned for this apparatus, but horizontal and vertical tail surfaces exist, whose function is to increase the aircraft's stability during flight. As Tesla stated, for the machine to take off vertically, a light and powerful engine was necessary, and for this, he primarily proposed the turbine described in his US patent 1061206 of May 6, 1913, which, according to him, not only fulfilled all requirements but was also specially adapted to operate at high temperatures.

It is evident that, according to Tesla, his turbine, not only in his aircraft but in aircraft in general, represented, along with the idea of vertical takeoff, the greatest value of this patent.

Two such turbines, in the drawing, along with other propulsion system devices, are fastened to the frame structure, taking into account the center of gravity and thrust.

It is characteristic of the description Tesla gives in his patent that it is not limited to precise technical solutions (except when it comes to his turbine engine), thereby showing that he was aware that technical innovations are applied more quickly in aviation than in any other field of technology, and thus avoided his patent becoming obsolete after a few years. He thus states that "conventional control devices" are installed on the apparatus, and "any known means of stabilization" can be incorporated. He further states that the wings are "vertical or slightly inclined," and likewise the shaft driving the propeller, which is "powerful and of such size and inclination that it can create a certain thrust and withstand impacts."

Power is transmitted to the turbine shaft via a gear reduction drive, where the turbines rotate in the same direction and neutralize the gyroscopic moment of the propeller. If two coaxially mounted propellers are used instead of one, the turbines should rotate in opposite directions. Seats marked 4,4,4 for the pilot and passengers are mounted on shafts 5,5, through which they can rotate up to a 90° angle, and springs and shock absorbers exist to limit and secure their movement for a given angle. Control linkages marked 6,6 7,7 7,8 are mechanical linkages connected to the controls, allowing the pilot to operate them with hands and feet from the seat regardless of its position.

When the engine is started and power is transmitted to the propeller, the aircraft rises vertically to a certain height, then gradually tilts and continues to fly more and more like a conventional airplane, with the initial supporting force of the propeller being replaced by the vertical reaction of the wings. During descent, the horizontal speed decreases, the machine briefly rises again, and then descends like a helicopter, with the propeller again supporting the descent. Landing can be performed with planning in case any part of the propulsion system fails, and for this purpose, a landing gear is provided, schematically shown in fig. 2 and marked 10,11.

Tesla describes his turbine in much more detail:

“In order to ensure the best result, I have found that it is in some way necessary to depart from the usual construction of my turbine and to incorporate into it such constructive elements and means for changing power, which increases from the minimum necessary for horizontal flight to values far exceeding its usual characteristics, which may be necessary in cases of ascent, descent, or sudden changes in speed. Furthermore, I have coordinated and dimensioned the fluid generator under pressure, the means for actuation and control so that for all operating conditions required by the machine, it can be instantaneously produced and utilized."

A better understanding of these explanations will be enabled by using Figs. 5, Fig. 4, and Fig. 5. In the first of these figures, the turbine operates as a rotary machine with gas expansion in the rotor, through the inlet opening 12, whose width changes by moving the piston 13, which can be freely adjusted in the channel via lever 14, which the pilot controls. The opening for the passage of elastic fluid is straight or slightly narrowed, so that a much lower speed is achieved than with an expansion valve, which easily allows for the best connection between the peripheral speed of the rotor and the fluid speed.

The characteristics of such a machine under constant supply pressure are, without significant limitations, proportional to the amount of working fluid passing through opening 12, and the machine is capable of carrying, for an indefinite period of time, exceptionally large loads, approximately three to four times greater than normal.

The strength and robustness of the engine, as well as its weight, do not necessarily have to increase significantly, from the aspect of centrifugal loads and critical speeds, unlike other engines where it is almost a rule that the weight is approximately proportional to the developed power.

To complete my engine, I further provided sufficiently large inlet and outlet openings. There are no serious obstructions here because air resistance and other losses truly do not exist, so most of the rotational work occurs on the peripheral parts of the discs. As shown in the figure, piston 13 is in a position proportional to the minimum operation. Part of the inlet opening is approximately 1/5 of the full opening that is achieved when the piston is in the extreme position marked by a dashed line. With the increase in the coefficient of contraction and backpressure that accompanies the increase of the inlet opening, it becomes possible for the opening to be made of parts.

Fig. 5 shows a different means for achieving the same goal. In this case, the engine operates as a true turbine, with the working fluid expanding almost completely through a divergent variable opening, 15, which is composed of several parts to achieve maximum performance. The outlet opening is also proportionally enlarged, as required in the example shown in Fig. 4. Power is changed using a throttle 16, similar to those used in automobiles. The throttle is placed in the line supplying the high-pressure air and carbureted fuel generator and is connected to the control lever 14. This generator has an adequate capacity according to maximum requirements, meaning I don't think it is much larger than what is usual, but rather it is constructed to provide energy when