Prior to the introduction of the Westinghouse air brake, steam locomotives were initially equipped only with hand brakes on the tenders used for holding while standing. Stopping locomotives was accomplished by reversing. Eventually, locomotive brakes powered by a steam cylinder came into use.

John White’s book, American Locomotives reports that by 1889, 12,000 locomotives were equipped with driving-wheel brakes. So the widespread adoption of locomotive power brakes on the drivers was well under way prior to the introduction of the Westinghouse air brake. Were these pre-airbrake locomotive power brakes all directly actuated by steam cylinders as universal practice?

Westinghouse received his first patent for an air brake in April 1869 and the air brake company was organized that July.

Railroads installed air brakes on locomotives, but were much slower with installing on freight cars.

Brian,

Thanks for that information. I was focused on the end date of the air brake conversion period when I mentioned the introduction of the air brake. But, as you say, there was a lot of time ahead of that final deadline to add air brakes to equipment. It makes sense that the railroads would have converted locomotives first.

From what you mention, air brakes on locomotives may have been commonplace by the early 1870s. Perhaps then there was very little development and use of the steam brake, and railroads moved directly from manual brakes on the tenders to air brakes on the drivers.

This is a topic where it can be hard to generalize. I was doing research on a group of switchers built by Baldwin for the St. Louis Bridge Company, a predecessor of the Terminal RR Association of St. Louis. Using White's book as well as Bruce's Steam Locomotive in America I found that the steam brake on locomotives started being used in the late 1860s. Westinghouse introduced his straight air brake in 1869 and the automatic air brake in 1880. Sixty two percent of American locomotives were equipped with air brakes in 1890 and 96 percent had them in 1900. Looking at the Baldwin specification sheets for the six 0-6-0 engines built for the Bridge Company in the 1880s I found that the first two had air brakes for engine and train. The later four were equipped with steam brakes, but had air brakes for use on the train only, not the engine. Of course switchers were not main line locomotives, but this shows how long it took for air brakes to become universal and how long steam brakes were used along with them.

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What prompted my question was thinking about the days before the introduction of power brakes on locomotive drivers. As far as I know, the practice of stopping during that era was to reverse the engine. When I think of reversing for stops during all the back and forth moves of switching, the concept seems rather awkward to say the least. However, I am not entirely familiar with how it was done.

Would the intent have been to actually to cause the drivers to turn in reverse to the direction of travel? If so, I would think that there would be a good chance of sliding the wheels and causing flat spots. Or could an engineer simply add enough throttle in reverse to create some backpressure that would decelerate the locomotive?

I have read several accounts of engineers reversing the engine, opening the throttle, and jumping off when a collision is inevitable. A common outcome was for the engine to get stopped prior to the collision, and then run away backward before the engineer could get back onboard to stop it. The reverse runaway often led to a worse wreck than what would have occurred had not the engineer reversed to avoid a collision.

[quote="Ron Travis"] However, I am not entirely familiar with how it was done.

Would the intent have been to actually to cause the drivers to turn in reverse to the direction of travel? If so, I would think that there would be a good chance of sliding the wheels and causing flat spots. Or could an engineer simply add enough throttle in reverse to create some backpressure that would decelerate the locomotive? [/quote]

That's exactly how it's done as long as the locomotive has a mechanical (non-air assisted) reversing gear. Also, when if one wants to stop the locomotive, the cylinder cocks need to be open when coming to a stop to allow for greater control. It's also more difficult to slide the wheels using reverse timing than making a hard application of the locomotive independent brake.

Believe it or not, not every industrial operation stayed with air brakes forever.

At SFHM, we have some information that after the logging company ceased hauling logs on the common carrier railroad and used only the woods tram, that they went and ordered steam jam brake equipment from Baldwin for the two woods engines, and removed the air pumps from the locomotives. They even removed the brake lines, cylinders and even the brakes themselves from the log cars. After this, they handled 18 car loaded log trains up and down 2% grades with nothing more than the engine brakes.

Oh, and this was in 1948-54.

For those interested, here is a short clip of the B&O William Mason on a test run with cab footage. Note at about .19 in the video, the engineer reverses, closes down on the throttle, slows, goes back to center, and eases to a stop. Another reverse on the johnson bar and ready for a reverse move.
Bruce

http://www.youtube.com/watch?v=D5CO4UoU3DE

The other surviving Mason has a steam jam on the trailing truck.

Actually the throttle was already closed for a brief downgrade. I went to reverse, opened the throttle a little, then closed it, went back to forward for a bit then reversed to stop and then back to center. Not trying to be nitpicky, but figured since it was me in the video I'd explain the process.

I can add that very rarely when stopping the Mason do we wind up giving it enough throttle to actually reverse the wheels. That would be highly frowned upon as we try to be gentle with our 154 year old. Once the reverser is put in the opposite direction, not much, and often no throttle at all is needed to slow to a stop.

Not every steam brake is a 'jamb' brake. In fact, most steam brakes had equalized linkage. Technically a 'jamb' brake is the type between drivers where the piston pushes down on arms that force the shoes against the wheels. There were air jamb brakes also.

C. Edwards,
Thanks for that insight into the fine points of using reverse to stop. And thanks to the rest who have supplied some information here. If I understand it, placing the locomotive into reverse valve gear when moving forward, even with the throttle closed, will create retarding force to the forward movement. Then if the throttle is opened, the retarding force will increase until the drivers first lock, and then slide; and if more throttle is added, the drivers will reverse.

I suppose with enough finesse, the drivers could be made to reverse slowly as the engine moves forward, but I would think that they could easily lose that reversing adhesion and spin out in reverse. So that would be four possible braking phases of reversing when moving forward:

1) Resisting the forward rotation of the drivers.
2) Locking the drivers.
3) Slowly reversing the drivers in relation to the forward travel.
4) Spinning the drivers in reverse in relation to the forward travel.

Which one of these four possible phases would provide the greatest potential deceleration of the forward traveling locomotive?

I am guessing the answer is #1 or #3, but I am particularly curious as to which one of those two would provide the greatest degree of deceleration. Perhaps they are identical in result.

I think I should clarify. Locking the drivers or reversing the direction of them while moving is something that is to be avoided at all cost. This whole process is intended to only put back pressure into the cylinders to slow the forward motion. Occasionally when overzealous an engineer can give it too much throttle in reverse and cause the drivers to spin in reverse. Like I said, this is a rare accidental happening, not anything that is ever tried for.

The answer is #1. Adhesion rates are always highest when the wheel is rolling, not sliding or slipping. That is why modern locomotives and MU cars have sophisticated spin control systems, and why when you drive your car in snow, you try to avoid spinning the wheels. Once the wheel begins to slide when braking, or spin when accelerating, the tractive force goes down. (Actually it turns out the highest adhesion occurs with just a very little slip in power and a very little slide in brake, but this microslipping is not noticeable to the naked eye.)