The Brennan Gyro-Monorail

Updated: 26 Feb 2015 Links added



Having found a gyroscopic monowheel, the Museum of RetroTech now (15 Oct 2001) proudly presents... a gyroscopic monorail vehicle. Here is a truly wonderful piece of work.

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.

In the Gillingham tests the vehicle was fitted with two petrol engines. A small 20 hp unit powered the gyroscopes, drove an air-compressor (for braking?) lighted the car, and propelled it at slow speeds. A larger 80 hp engine was used for high-speed propulsion.

Brennan patented the concept in 1903; see patent No 27,212, with the unsensational title "Improvements in and relating to the Imparting of Stability to otherwise Unstable Bodies, Structures or Vehicles".

Left: The Louis Brennan gyroscopic monorail, demonstrated to the press at Gillingham. Kent, on 10th November, 1909. Note the soldiers standing on the rear platform- apparently 40 of them. The sleepers of the test track were 3.5 ft in length, laid 2.5 feet apart without ballast. The steepest gradient on the track was 1 in 13, and the sharpest curve had a radius of only 35 feet. Note the double-flanged wheels to prevent slipping off the rail.

Left: This looks like a test-track to prove you could back it in a wye and so turn it round. If this machine was intended to pull wagons or coaches in the usual way, then there appears to be a problem. Surely each vehicle in the train would need its own gyro-balancing system, complete with power supply? Furthermore, it only take the momentary failure of one gyro system to cause the mother of all derailments. Not a war-winning weapon, I feel, and I imagine the War Office thought the same thing.