The Brennan Gyro-Monorail was developed by the Irish-born Australian inventor Louis Brennan (1852–1932). It was 40 feet long and weighed 22 tons, and was designed to carry 10 tons. Speed on the level was 22 mph. The vehicle was balanced by two vertical gyroscopes mounted side by side, and spinning in opposite directions at 3000 rpm. Each gyroscope was 3.5 feet in diameter and weighed 3/4 of a ton each. They were enclosed in evacuated casings to reduce air-friction losses. The rotational axes were horizontal.
Traveling on one tiny rail, the monorail train took corners at speed and sharp angles, climbed and descended steep mountains, successfully negotiated earthquake damaged sections of rail and traversed gorges sans viaduct – all in miniature, of course, but proving that a scale-up model would be equally effective.
Inspired by a wind-up toy he had bought for his son, the monorail train was kept steady by a couple of gyroscopic stabilizers called gyrostats. Brennan’s original concept was for its military uses, as the track could be laid down much quicker and travel at twice the speed than normal double track lines (as well as a smoother journey), but it was also obvious that it would have uses anywhere that double-track railways were impractical or costly to build.
Patented in 1903, the garden model was demonstrated to the Royal Society in 1907. A scaled-up system was successfully demonstrated to the press in 1909 and they loved it, nicknaming it the ‘Blondin railway’ after Charles Blondin, a tightrope walker who had traversed Niagara Falls.
One of the biggest supporters for the monorail project was Winston Churchill, who solicited practical and financial support from the War Office and from India, supplementing the considerable amount of Brennan’s own fortune that he had sunk into the project. When Churchill came to view it, he remarked, “Sir, your invention promises to revolutionize the railway systems of the world.”
Brennan again demonstrated the monorail at the Japan-British Exhibition in London in 1910 and, with British Prime Minister Herbert Asquith volunteering to take a ride, it won the Grand Prize.
Despite this accolade, the press and senior government support, there were still concerns about its safety: that if the gyrostats failed, the train would topple. Brennan assured people that these fears were unfounded, but this fear and pressure from the double-track railway industry meant that all his backers gradually withdrew from the project.
Brennan was now financially ruined, forced to sell his house, return to work and the monorail project abandoned. Over the years, several monorail systems were developed but they would not be seriously considered again until the 1980s, when its practical application in densely populated urban areas was implemented in places like Hong Kong, Germany, China and Japan.
Luckily, the engineer was able to find employment, if not as well paid as his previous role. For the duration of World War I in 1916, Brennan worked for the Ministry of Munitions inventing refining top-secret munitions. After this, with the help of his erstwhile supporter Winston Churchill, he persuaded the air ministry to support him in the invention of a practical helicopter.