With a quiet background (countryside night time) 6–8 miles. Suburban, 2–3 miles. Loud city, 1 mile if you're listening for it.
People Also Ask
Sound can travel a very long way, especially if there are no buildings or hilltops to soak up the sound. If you live somewhere very quiet and very flat then I would not be surprised to hear a horn from miles away.
When air warms with altitude a temperature inversion exists. Sound travels faster in warm air than it does in cool air. This means the sound of a train horn will bend downward when it passes through an inversion causing sound waves to propagate farther than normal.
If I am up to an education center that I help out at I can hear trains down in the valley about 800 ft below all the time. This is about 6 miles. On a cold clear night I can hear trains at home. This is about 8 miles away.
Anyway, don't blame the engineer: They're required to blow that horn. The regulation in question is called the Final Rule on the Use of Locomotive Horns—a name that strongly implies they've had just about enough of your bitching—and it requires four blasts 15 to 20 seconds before every crossing.
As you saw from the DJD Labs test above, actual huge cast-metal locomotive horns top out at 149.4 decibels. Do you think a little electric horn or air horn can do more than 150 decibels? To put things in perspective, a firecracker or a shot from a rifle is around 150 decibels.
The reason that trains honk their horns so much at night is because it's dark and the trains aren't so easy to see. Even though the lights are on, we sometimes can't see them coming, especially around the many blind curves near or ahead of the train station.
Train brakes hiss because they use pneumatic braking systems. When a train comes to the final destination the air in the system is dumped out to 'park' the train like pulling the parking/hand brake on a car. The brakes normally are on without air so air is pumped in to hold the brakes off when the train moves.
In a quiet zone, railroads have been directed to cease the routine sounding of their horns when approaching public highway-rail grade crossings. Train horns may still be used in emergency situations or to comply with other Federal regulations or railroad operating rules.
If you hear, two small horns, it means the motorman is asking the guard to direct the railway signal to start the train. In case you hear three smaller horns, it suggests that the motorman has lost control over the train. This also acts as a signal to pull the vacuum break immediately. This signal is rarely heard.
Locomotive horns serve a utilitarian function and in North America with its wide open spaces, sparsely populated areas between cities and infrequent rail traffic (compared to Europe) a louder horn and more frequent blasting makes practical sense.
Train horns must be sounded in a standardized pattern of 2 long, 1 short, and 1 long blasts. The pattern must be repeated or prolonged until the lead locomotive or lead cab car occupies the grade crossing. The rule does not stipulate the durations of long and short blasts.
How many decibels is a real train horn? Car horns and train horns are measured differently because of their size, a train horn is much bigger and can create more noise. Train horns are typically between 110-140 decibels in sound level!
Two short whistles mean that the engineer acknowledges that he or she heard or saw a signal that affects movement. Three short ones mean that the engineer intends to make a reverse movement. Two long, one short and one long mean trains are approaching a highway or street crossing. And the list goes on.
Modern diesel and electric locomotives primarily use a powerful air horn instead of a whistle as an audible warning device. However, the word whistle continues to be used by railroaders in referring to such signaling practices as "whistling off" (sounding the horn when a train gets underway).
This rule applies 24 hours a day, even if a crossing is equipped with lights, bells and crossing gates. Train crews also may deem it necessary to sound a horn as a warning when there is a vehicle, person or animal near the tracks.
Crossings: 2 long, 1 short, 1 long - means train is coming. That last long is to be held until the train has occupied the crossing. Also, not all crossings require a whistle. Fire: 3 short, pause, 3 short - warn nearby people/crews/etc.