Hey Y’all; a question relevant to one of my HLW Mack bashes:
Could sound pressure from locomotive air horns damage a locomotive headlight if the two are too close together?
Would it make a difference whether the real-world prototype headlight involved was incandescent or LED?
Would it make a difference whether the real-world prototype horn involved was single-chime or multiple chime?

I would think the only possible damage could be vibration, but I would assume that the filaments in locomotive headlights are designed to resist vibration.

Pressure no, it could not cause a sealed headlight to implode.

LEDs can handle more vibration than incandescent filiments.

If you wanted a theoretical answer, with multiple chimes, you would have more chances for a damaging vibration, however slight.

Greg

For a time, the horns on the B class Clydes were mounted on the nose, right above the headlight. It didn’t seam to cause any issues with the light. The engineer’s hearing and visibility are a different story.

Acoustical engineer here. No, there’s not nearly enough pressure. As Greg suggested, the structure-borne vibration path would be much more significant, but likely negligible compared to the other sources of vibration in a locomotive.

Most destructive structure-borne or sound-induced vibration is at very low frequencies. Train horns don’t produce much energy in that range.

Okay, thanks y’all!

Oh, and here’s the specific HLW Mack in question.
Last night I finally felt up to working on trains again and got the molded on headlight fittings sawn off.