By Joan Whetzel
The coal-black smoke billows behind the smokestack, trailing off to a wisp of gray as the winds carry it away. The rhythmic, clickety-clack of the wheels rolling along the tracks lulls the passengers into a calm anticipation of arriving at their destination. The whistle blows, sounding its coded warning to people waiting at the next railroad crossing, or delivering a message to the railroad crew at the next station. That railroad whistle has become the iconic symbol of trains, and the adventures of riding the rails. But most people don't know how the tradition of the Railroad whistle got started or what the whistle codes mean.
What Are Railroad Whistles?
Trains, because of their large size and mass, don't stop quickly. They take a lot of time and space to come to a full stop. As railroad transportation took off in Europe and North America, more and more accidents involving trains began occurring, mainly because people were either unaware that the train was approaching or oblivious to just how close the train was. It was for this reason that, in the early to mid 19th century, it became increasingly necessary to have some sort of signaling device to warn the public of approaching trains - and to send messages to railroad workers at the next station as the train approached from a distance. The first steam-powered, train whistle - called a steam trumpet - was invented for the Leicester and Swannington Railway by a local musical instrument maker. Later, as steam engines were phased out and diesel engines took over, diesel train whistles, or horns, were invented. The type of whistle used depends on the type of train (usually tied to specific railroad lines) and to the size of the locomotive. Smaller locomotives have somewhat muted whistles compared to the large locomotives which tend to blare quite loudly.
Types of Whistle Signals
Steam engines were activated with a tug on a pull cord or by pulling on a lever in the locomotive. This allowed steam from the boiler (heated by the coal) to flow through the whistle, creating the whistle sound. This lever or pull cord system gave the locomotive operator a great deal of control over how the whistle sounded and allowed him to create his own unique whistle blowing style The North American steam whistles came in a variety of types from single-note to 5-note or six-note whistles. The modern diesel whistles are operated with a pushbutton, which removes some of the operator's control over the whistle's sound but allows for more standardized whistle or horn tones and removes the guesswork from determining, exactly, what the operator is trying to communicate.
At first, each locomotive operator used his own style of whistle blowing. On the one hand, it made it easier to tell which operator was signaling because of his unique whistle signal style. However, it quickly became confusing with so many different styles. So a standardized whistle code was developed, and which evolved over time, to become the whistle code used most commonly today. The whistle code, like the Morse Code, uses a series of short (dots) and long (dashes) blasts to relay specific messages.
It is necessary to use train whistles when approaching grade crossings and to make them loud enough for automobile drivers to hear the trains coming while inside cars with more and more sound proofing features. However, with the ever growing number of trains, the proximity of railroad tracks to neighborhoods and businesses, and the sound of diesel air horns that can be heard for miles, sooner or later, noise complaints were bound to start rolling in. A conflict between railroad/auto safety and quality of life issues has emerged. Many railroads have increased their traffic during the nighttime hours, when there are less cars on the road, to help lower the incidence of car/train accidents. Unfortunately, this has increased the amount of train whistles piercing the night air, disturbing the sleep of homeowners who live near the tracks. It's enough to make a person lose a good night's sleep pretty much every night of the week.
To resolve the noise issues, and reduce the number of noise complaints, many railroads in the United States (under Federal Railroad Administration regulations) have issued "quite zones" in residential areas. In these quiet zones, rather than the locomotive operator blowing the horn on the train, a much quieter whistle is sounded at the grade crossing as part of the railroad signal system. As the train approaches the grade crossing, it passes over a signal box that triggers both the railroad arms to go down and the grade crossing whistle to blow. This grade crossing whistle is blown through a speaker which is aimed downward toward the street, and can be heard only by motorists close to the grade crossing. The locomotive operator receives a flashing orange "x" signal on a signal post next to the track to warn the operator that he or she is entering a quiet zone and that the train's whistle should not be blown.
Still, there are many folks out there who don't object to the train whistles, even at night. Besides being a necessary safety feature, the sound of train whistles bring a sense of nostalgia, pleasant memories of past trips on the train, the promise of adventures yet to come.
To hear what the different types of train whistles sound like, check out this site. Simply click on one of the sounds (diesel, horn, whistle, steam) and listen to the different whistles.
Conway Scenic Railroad website
The Sounds of Train Horns website
Wikipedia. Train Whistle.
Conway Scenic Railroad. Train Whistles!
Democratic Underground. Train Whistle Code.
Indian Railroad Fan Club. Signs, Whistle Codes, Flags, and Hand Signals.
Everything 2. Whistle Code.