|Automatic air brake (2002)
The automatic air brake — a braking concept invented by George Westinghouse over a century ago — remains the most practical and efficient system to safely control the speed of long and heavy trains.
Developed in response to the industry’s need for a safe and reliable air brake system, the automatic air brake replaced “straight air” systems that were previously employed on early Canadian railway operations. The implementation of the automatic air brake system allowed railways to operate longer trains safer, eliminating among other factors the need for “brakemen” to run from car to car on the top of each train to manually adjust individual handbrakes. This practice, employed in particular on heavy gradients, was highly risky and often resulted in “run-aways.”
Using a pneumatically (air) activated system, the automatic air brake system spreads braking force out over each brake shoe on each car marshalled together on a train. A “brake pipe” - made up of underslung pipes and hoses, together with specialized reservoirs on each car — runs the length of the train using the automatic air brake system. The brake shoes on each car release when the “brake pipe” is pressurized to a specific pounds-per-square-inch level with air supplied by large reservoirs located on the locomotive. The brake shoes apply to slow or stop a train when a reduction of “brake pipe” pressure is made using the automatic air brake valve on the controlling locomotive, or emergency air brake valves.
The Canadian Railway Hall of Fame has recognized the revolutionary aspect of this invention and its role in the safe and efficient operation of North American railways for over one hundred years.