It happens that a person who, in childhood, is attached to some kind of toy, then retains this attachment for the rest of his life. The Australian engineer and inventor Louis Brennan apparently had a spinning top with such a toy. Not the one that comes and bites on the barrel, but the one that spins, keeping balance. In other words, a gyroscope.
For almost half a century, Brennan has been creating moving devices based on flywheels and gyroscopes, however, none of them, for various reasons, became widespread. His very first invention turned out to be the most successful. In 1877, at the age of 25, he patented the original external drive torpedo, in which two massive rotating steel wire coils acted as gyroscopes to keep the projectile on course. In 1886, after revision, Brennan's torpedoes were adopted by the British Navy and stood on alert for 20 years, and the inventor received a substantial amount spent on further research.
In 1903, Brennan filed a patent for a monorail motor-car held upright by gyroscopes. In 1907, a working model of a motor car was built and successfully tested, and in 1909 a full-size model was made with two 20-horsepower gasoline engines, capable of carrying up to 50 passengers at a speed of 35 km / h. Brennan's gyroscopic railcar attracted a lot of public attention, but not investors.
Although monorail tracks cost almost half the price of conventional ones, the system still turned out to be economically unprofitable, because the Brennan locomotive could not tow ordinary trailer cars. Each car needed its own flywheel for balancing, and, accordingly, an engine to spin it up. This made the train too expensive to manufacture and operate, and the railway workers considered it unreasonable to build monorails to drive single motor-cars along them. In addition, a significant part of the power of the power plant of such a motor car was spent not on movement, but on balancing, that is, on periodic unwinding of a heavy flywheel. As a result, Brennan's monorail remained in the category of useless technical curiosities.
Louis Brennan (second from left) with a model of his monorail motorcycle.
Structural diagram of the balancing mechanism with two flywheels-gyroscopes and the motor car itself when viewed from the front. Two large cellular radiators are installed under the glazing of the driver's cab.
"Rope Walker Car" with passengers and cargo.
Switching from railroads to aviation, Brennan in 1916 proposed to the British military a project of a very peculiar helicopter, which was a "flying top" with a huge propeller and a small cockpit below it. The main rotor was driven by a radial motor mounted above the hub, and not directly, but with the help of two auxiliary "spinning" screws connected to the motor by long cardan shafts that passed inside the blades.
To counter the reactive moment and control the apparatus, a whole system of four vertical and four horizontal screws was provided, mounted on a cruciform frame and connected to the motor by power take-off shafts, and with the pilot's cabin - by rods for controlling the number of revolutions.
Above is a patent drawing of Brennan's helicopter. It is not entirely clear what was the point in such a "cunning" design and why the inventor did not make a direct drive of the main rotor from the motor. I do not know how Brennan answered these questions, if he was asked them, but he managed to interest Winston Churchill himself with his invention, who "pushed" funding for the construction and testing of the prototype in the Department of Munitions.
The construction of the helicopter was delayed, as the inventor constantly made changes to the project, and the receipt of money from the ministry decreased after the end of the world war and the cuts in the military budget. Nevertheless, by the end of 1921, the device was built, and on December 7 of the same year, that is, exactly 95 years ago (which is why I remembered Brennan today), its flight tests began. In the final form, the helicopter was markedly different from the original project. "Spinning" propellers moved to the ends of the blades, ailerons appeared on the blades, which were supposed to play the role of a swashplate, the frame with balancing-tail screws disappeared, and the cockpit took the form of a small aircraft fuselage with a rudder on the tail.
Between 1921 and 1925, Brennan's helicopter took off about 70 times from the ground, but never once did it manage to rise to a height of more than three meters, that is, the climbs were largely carried out due to the "air cushion" effect. It was impossible to call them full-fledged flights, moreover, the device was not actually controlled in the air. During the tests, Brennan continued to finish and alter the helicopter, constantly requesting money from the military department. In the end, the military got tired of this and in 1926 they closed the project, recognizing its failure and writing off the 260 thousand pounds spent on it at a loss.
Brennan's helicopter at the airfield during testing. Note the two additional short propeller blades installed in one of the modifications.
At the end of his life, Brennan, who was already well over 70, built a prototype of a two-wheeled gyroscopic car, but this development, like the motor car, did not interest either buyers or manufacturers.
