Rail crossing signal from locomotive.

[captken]

I have asked at least 10 rail engineers what the crossing signal means and they don't know. Two longs a dash and a long is Morse code for "Here comes the QUEEN'S MAIL.

[tomikawaTT]

Another entry in the, "Meaningless coincidence," category.  The United States never acknowledged any queen as sovereign, and the proper term is (and always has been) "Royal Mail."

International Morse Code letter Q is simply that - a letter.  The third least used letter in common English.

Two long, a short and a long held until the locomotive enters the crossing has always meant, "Get out of the way.  Train coming through."

Chuck

[Deggesty]

And, the signal, many years ago, used to be two longs and two shorts. Possibly, in the beginning only one blast of the whistle was heard; then it was realized that more warning was needed, and instead of one prolonged blast several blasts were used (I think this would gain more attention than a single blast), and some people in authority realized that there should a standard signal which would have the particular meaning, "Clear the crossing!" I can comprehend changing the last blast to a long blast that is held until the train is in the crossing.

[pajrr]

I like to Describe it as "LOOOOOK  OUTTTTTT!  the  TRAINNNNNNNN!"

[jeffhergert]

tomikawaTT

Another entry in the, "Meaningless coincidence," category.  The United States never acknowledged any queen as sovereign, and the proper term is (and always has been) "Royal Mail."

International Morse Code letter Q is simply that - a letter.  The third least used letter in common English.

Two long, a short and a long held until the locomotive enters the crossing has always meant, "Get out of the way.  Train coming through."

Chuck

The change in the whistle signal for crossings from two longs and two shorts to two longs, a short and one long happened in the 1920s for most railroads.  The Morse code used by the American railroads wasn't International Morse.  The American code "Q" (.._.) isn't the same as the International code "Q" (_ _ ._).  

Jeff

[cacole]

According to some references I have seen, some railroads had their own unique version of Morse code that was totally unintelligible to competing railroads.

[rgbpainter]

The signal should be held until the locomotive has reached the far side of the crossing, completely filling it, at least in the USA.

[CHARLES SLEDGE]

While that may be what the current signal represents in a version of Morse code, remember that it started out as two long and two short blast of the whistle. As a result of numerous collisions at grade crossings the signal was changed to require the two long, one short, and a long that is to still be sounded when the locomotive enters the grade crossing.