When coming to a stop, I've noticed that engineers gently and subtly allow the train slack to run in, presumably to provide a smoother start-up and not jerk the passengers around. Technically speaking, what does the engineer "do" to the engine/train brakes to make this happen?

Generally, closing the throttle will cause a gentle bunch of the slack, as locomotives tend to not roll as freely as car bearings. Some will depend on the speed and type of brake equipment in use. From slower speeds, they could simply close the throttle and make a light automatic brake application and not bail off the independent. This would allow the locomotive brakes to be applied along with the train and also cause the bunching action. This works well on short trains, but under heavier braking, the engine may tend to grab harder, causing too much slack run in. The engineer can bail or feather the engine brake just to maintain enough pressure to keep the slack in while the train brake is applied heavier for the actual stop. Another method, though I'd only recommend it on short light trains, would be to utilize mainly the engine brake to slow the train and then only use the train brake once the train is stopped. Of course, this can cause severe slack run in, or sliding wheels if the train behind is too heavy.

My personal preference for stopping passenger trains is to stop with the slack stretched to avoid the runout of slack from each coach as you start out. I apply a minimum reduction to stretch out the train and then very gradually close the throttle but leave enough steam going to the cylinders to keep the slack stretched, I always immediately bail off (release) the locomotive brakes with each brake application, then I will add to the initial reduction to get my speed to decrease at a rate so that I will only need to add a slight reduction to stop the train at the correct location. A revolution or two of the drivers before the final stopping point I will ease the throttle all the way closed and let the train brakes bring the train to a nice easy stop. Obviously one would use slightly different techniques based on uphill or downhill grades at the stopping point and the weight of the train consist. Sometimes it is necessary with a heavy train to stop with the slack bunched, in order to even start the train on a steep grade, it is an art form to get all the cars rolling forward before the brakes release on the last car and it rolls backwards before the car ahead of it violently jerks it back forward.

Mike Tillger

I've seen people thrown violently across a coach, even on a three car consist, when someone tried to use only the engine brake to keep a train's speed in check. I would NOT recommend this practice to anyone.

Old timers who routinely ran passenger trains taught me to never shut off power on a diesel powered train, until you had come to a complete stop, AND applied the independent brakes. Use the air to slow the train, and keep minimal power on to keep it stretched. Only shut off after the train has come to a complete stop. Likewise, for starting, the train brakes were not to be released until after minimal power was applied first, and the engine brakes carefully released, to draw out an inadvertent slack gently. Once the slack was out, the releasing train brakes and minimal power would ease the train away with no violent jerking action. You could then follow that start with whatever power was necessary to get the train up to speed quickly.

I had the opportunity to do this, and was coached to "power" the train into the station. Approaching the platform, the engine brakes were "bailed off", and the throttle kept open to drag the train to the exact stop point.

My understanding is this is pretty typical.

I think its been the habit to "Power brake" keeping slack out to avoid jossling. Careful brake/power manipulation you could slack in. Reason for tightlock couplers but with museum lines they don't always have this. Tomlinson Couplers have no slack, used for many interurban/streetcars.

I was taught to stop the train in 2 different manners, depending on what the next move would be.

If the next move would be in the same direction as the train is currently traveling, stop the train using the train air, with the independent bailed off. This keeps the slack stretched (or bunched, if pushing), and allows a smoother start without slack action. This same method would also be used to slow the train without stopping.

If the next move will be in the opposite direction of travel, stop the train using the train air, but do NOT bail off the independent. This allows the slack to gently roll in (or out, if pushing) while the train decelerates, and allows a slack free start.

Jeff

I have always kept the slack stretched when making a stop, steam or diesel. The difference between the two is although you can leave the diesel throttle open about Run 1, once she stops, hit the independent then close the throttle. Starting out, put her in Run 1, release the train brakes, feather off the independent, and off you go.

Steam..keep 'em stretched, then once you are where you want to be, a final applicaton, if needed, and once she stops, set the independent then close the throttle, to keep the engine from lunging back into the train.

Be careful when power braking with something small like a 44 or 45 tonner; those smaller traction motors don't like it. A friend, some years ago, traced some of his 44 tonner's TM problems to power braking; his crews would almost come to a stop a bit short of the station, then open the throttle and pull up the last few feet against the train brake. I believe he changed two motors one summer before he realized what the problem was.

Hi Kurt,

We are always trying to give our passengers a smooth ride on the M&H. Each railroad and its equipment has its own characteristics so we must be governed accordingly. When stopping at our station in Middletown, we are coming alongside a platform with a limited boarding area and a bumper post at the end of track (which we do not want to hit!). A light application of the automatic at a reduced speed less than 5 mph with the independent bailed allows us to make a safe smooth stop on the mark usually with some low power shoving. Then the throttle is closed and the independent is applied. The slack would be bunched though so when leaving, since the GE centercabs have no throttle notches, I normally have the automatic in hold and then slowly bail the independent while applying throttle. At the bridge where we now stop, or at unprotected grade crossings where we are required to stop and flag, I usually apply the automatic at the required distance depending on train length and weight and bail the independent using some throttle to keep the train stretched till we stop. This allows a smooth start. The Alco's are much different and easier to use on a tourist train than the GE's and provide a smoother ride but that is another story! Which I think you have already heard!

It all depends on what you are doing......freight or passenger and of course how you were taught.....
Here's what I was taught:
If stopping and then continuing in the same direction.....you pull with a minimal brake application on the train, bail the independent off and use throttle lightly, reducing it to the stop......you must estimate your stopping distance, etc....takes practice.....
If stopping and reversing movement.....with a small passenger train.....you want to try to stay off the train brake, use the independent with a "fanning" motion, to slowly, lightly slack the train in......making a train application just as the train stops to hold position.....again, this all depends on the situation....is the station flat, uphill, downhill, etc, etc....
The objective is to minimize bumps, etc to provide maximum passenger comfort and safety....
I was taught that what many of you are calling "power braking" is actually "stretch braking".....power braking is working the locomotives brakes against its throttle.
Then there's freight handling......"kicking" cars with no air on them and stopping with only the independent, etc,etc....

You do whatever works for your consists & physical characteristics. There will always be good train handlers & others, the point is to be educating your staff (if they can be, that is).

And remember, if you spill the drink of the brass in the porch car - you WILL hear about it!