Horn placement

Trains Magazine General Discussion
1

Any reason for this or just an experiment?

http://www.rrpicturearchives.net/showPicture.aspx?id=473608

http://www.rrpicturearchives.net/showPicture.aspx?id=473609

Thanks

2

Maybe it’s a clearance thing like the EL SD45’s and SD45-2’s had, something similar to that?

3

That’s a wierd place. Although the tend to move the horns toward the middle of the carbody, and away from the cab, to protect the crew’s hearing.

Maybe it has something to do with maintenance.

Nick

4

Horn placement is really all a matter of the railroads taste. Older locomotives have their horns mounted on top of the cab, but this is so loud for the crews that on newer locomotives (and some older ones) they’ve moved them back near the exhuast stack. Unfortunantly some are placed behind the exuast stack, and when an air horn has a constant diet of diesel exhuast, it doesn’t sound that great anymore. As Zach pointed out, there are clearence issues on some lines, so perhaps that’s why that NS geep has it mounted on the side.

5

Another reason for the mounting near the exhaust is that it keeps the horns functioning better in snowy/cold weather. Although it is still a good idea to sound the horn while busting through drifts to keep the horn from plugging with snow.

6

Anybody else see a problem with having those horns mounted on the right side? I’ll bet the rear cab door doesn’t stay open when this unit is out on the road!

(I suspect that the horns were moved there when the a/c was installed on the cab roof. On the UP, they moved the horn sets higher, but still kept them up front on some of our SD38-2s that were retrofitted with air conditioning–no clearance problems, apparently. Still, wouldn’t the left side have been better?)

7

Easier to run the air line to them there than on the other side?

I was going to mention the retrofit A/C as the reason, too.

But Santa Fe managed to keep them on the roof along with the A/C included.

8

Check out some of the photos on railpictures.net of EMD locomotives in Australia. A lot of them have horns mounted on top of the nose!

9

Dunno how much “protection” is afforded by aiming the horns AT the Crew!

And with the cab partially blocking the horns to the front, and almost totally blocking towards the left front … they’re not going to give much protection as a warning device.

10

That would be the CLP and GM class, they look like a F unit on 6 axles… I have no idea why they are on the nose, but it probably stems from the days of when the railroad that owned them was a government railway (commonwealth railways) and to make the horn more audible.

11

Emergency vehicle sirens can no longer be mounted on the roof. OSHA (and others) require them to be mounted forward of the passenger compartment. I’m surprised the railroad industry hasn’t been subject to similar requirements.

Mark

12

For one thing the railroads aren’t subject to OSHA, they are governed by the FRA. The FRA’s regulations are geared toward public safety and crash surviviablity, not crew comfort. Cab layout and horn placement are typically union issues.

For another, locomotives operate in both directions. Take a close look at the trumpets of an air horn, they normally face in both directions. The railroads are aware that horns mounted over the cab are damaging to the crew’s hearing. That’s why the horns are being moved to the middle of carbody.

Nick

13

This is a SWAG. It is just a SWAG. Any correlation between this SWAG and actual truth is merely coincidental.

They wanted to put them on the roof of the long hood just foward of the #1 fan, but cab roof AC reflected too much sound and they couldn’t make the 96dB required 100’ in front of loco. Elevating the horn would have resulted in clearance issues for places they want GP38s to operate. Putting the horn on the cab would make the noise level in the cab too high. So, the side mount fixed the problem without dual horns and/or miles of plumbing.

The concludes the SWAG.

14

I still see a number of 2nd generation CSX units (and foreign power) with horns on the roof.

Management probably “snubbed” the idea because of the costs, but to help with the noise an insulation pad of sound/vibration absorbent padding ( rubber, urethane) could be placed onto cab ceilings. With closed windows this material does work.

I’ve seen it. It’s used frequently in industrial plants where continously running A/C units and generators emit 100+ decibals. The material is installed on doors and walls.

Though expensive, it seems that it would be worth it if it helps protect the hearing of locomotive crew members.

I worked for a transit company, so I can almost guess what managment’s arguments would be:

  1. Crews won’t always keep the windows closed.

  2. During switching manuevers in towns the conductor or switchman on the ground would still be exposed to the horn

  3. The material wears out over time…

  4. Studies would need to be performed

  5. Yada…yada…yada…

15

EJ&E and some other roads have had a tradition of rear mounted horns… I asked a crew guy about it once, and he said they did it simply because they got tired of hearing the horn in the cab. The AC seems to have dislocated the antenna on that NS unit as well… It’s not going to radiate as well mounted on the side like that. Dave http://www.dpdproductions.com - Featuring the TrainTenna Railroad Radio Antennas -