Train horns have been in use since the first locomotive was invented. Engineers use the horns to scare wild animals off the track, and to alert oncoming traffic of the presence of a train approaching a railroad crossing, they are used also to alert passengers that are boarding that it is time to leave. Railroad employee’s often use a train horn when they are working on the tracks and during the switching operations.
When internal combustion began to power the locomotives, the air horns from trucks were used but were not loud enough to be heard over the powerful diesel engines that the locomotives were using. The truck horn design was then upgraded by the railroad company, using oscillation to push the air through a power chamber and vibrate against a nozzle. The position of the diaphragm will allow more air or less air and the constant oscillation of the diaphragm creates waves of air that causes it to produce the sound of the horn. The North American locomotives that were manufactured before 1990 still used the old manual pull cord technique that was known as feathering, which just meant modulation was possible for the horns loudness. During the 1990s locomotive began using pushbutton controls and a pedal was built into the cab below the floor and when the pedal was pressed, it sounded the train horn.
In the past few years, train horns have become a sort of fad with many vehicle customizers for their own personal trucks and vans. Train horns are not manufactured for private use because people know that when they hear one there is usually a train coming, and if a train horn is used in normal traffic it tends to cause accidents, and in many places, it is against the law to operate a train horn. Train horns themselves have even come under scrutiny as some communities have developed quiet zones, and the engineers were instructed only to sound the horns in case of an emergency. Because of these laws, many automobile and pedestrian accidents have happened. With the speed of a train, and the amount of weight behind the engine a train hitting and automobile is like a truck running over an aluminum can, the can will be flattened.
The patterns to the sounds of train horns have different meanings depending on the rail company, as well the country.
In the United States, the pattern for train horn signals at a crossing is two long, one short and one long, which will be repeated until the train has crossed the railway crossing. Florida had put a ban on locomotive horn use because of quiet zones that had been established, and after a few years had to lift the ban due to the enormous rate of accidents that had accrued during the ban.
Although many find train horns irritating, they have a very important purpose and hopefully quiet zones will fall into disuse as people come to understand the importance of train horns.
Author: Yves B. GellerThis author has published 2 articles so far.