The Friends of the 261

Firing a big mainline steam locomotive is an awesome experience. Anyone who has had the chance to ride behind our engine and experience the tremendous display of power during a run by knows the feeling of brute strength a steam engine exudes while working hard. Being one of the engine crew responsible for keeping that force harnessed safely and for getting the locomotive over the road is a major responsibility. Doing it correctly and efficiently gives me a great sense of satisfaction. I have been on the rebuilding and operating crew of the 261 since 1992. In this short essay I want to share with you some of the approaches I take to firing this engine, and to answer some of the many questions I am often asked about it.

"Safety is of the first importance in the discharge of duty." So begins the opening chapter of the Fireman's Manual for the New York, New Haven and Hartford Railroad Company in 1946. Safety was also the governing principle in both the design of the locomotive in 1944 and in its rebuilding in 1992-3. For example, there is a safety factor of four built into the design of the boiler. That basically means that a pressure vessel that is limited to a top pressure of 250 psi such as our locomotive is actually built to be able to withstand a pressure of 1000 psi, or four times as much as its top operating pressure. Appliances such as our Barco Low Water Alarm are designed to be extra fail-safe backups to the normal appliances used for ascertaining the water level. Over a half century later, safety is still at the top of the list of priorities in the execution of our duties as firemen. We will talk about the two duties that most directly relate to this: maintaining the proper water level, and maintaining a good fire.

The fireman must know the actual level of the water in the boiler at all times. Milwaukee 261 is equipped with a water glass mounted directly on the boiler on the fireman's side, a water glass mounted on the water column on the engineer's side, as well as three gage cocks also mounted on the water column, all of which help to determine the water level in the boiler. To make sure that the water glasses are reading the water level accurately, we blow out the glasses and their steam and water valves several times a day to keep any impurities from clogging the valves and perhaps giving a false reading. We also do several "quickie " blowdowns of the water glass using just the drain valve to test the quickness of its refilling which also helps to determine the accuracy of the reading. Finally, we test the reading of the water glasses against the gage cocks which are the truest reading of the water level in the boiler. By doing these multiple tests repeatedly and often, we are confident of the accuracy of the level of water we see in the glasses.

After we have determined that the water glasses are reading accurately, we have to interpret that reading depending on what the locomotive is doing. If we are stopped on level ground and on tangent track, the water glass will accurately show the level of water in the boiler. In virtually all other situations, the water glass reading will need some degree of interpretation. When the locomotive is accelerating forward, the water will pile up toward the back of the boiler, giving a higher reading. When the engineer is braking, the water will pile up towards the front of the boiler, giving a lower reading. (Running in reverse gives the opposite effects.) Super elevated curves affect the reading, as well as the train's speed going around it. Even when running on level tangent track, the rising steam bubbles in the water between the firebox and backhead will cause the water glass attached directly to the backhead to read a bit higher than normal. The biggest factor affecting water glass levels, however, is climbing and descending grades. Water will always try to remain level, whether the boiler is level or not. For that reason, on ascending grades when the back end of the boiler is lower than the front end, the water will show higher in the water glass than if the boiler were level. On descending grades, the water is lower in the back of the boiler. Since that is where the crownsheet is located, the fireman has to make sure he has a sufficient level of water to keep the crownsheet covered at all times and under all these conditions.

The second major responsibility the fireman has is maintaining a proper fire which will produce the amount of steam that the locomotive needs at any given time to accomplish the task at hand. We usually burn a soft bituminous stoker coal which has good heat content and seldom clinkers up. On the majority of our trips with the Milwaukee 261, the locomotive is pulling far less than its rated tonnage, so we generally keep the fire as light as possible, usually about 4" to 6" deep with a bit more in the back corners and around the edges. This is thick enough to keep the fire on the grates, and still allows plenty of air to be pulled through the fire. It takes 300 cubic feet of air to burn one pound of coal, and since we average burning about 1.5 pounds per second, we have to pull 450 cubic feet of air through the grates every second to provide sufficient oxygen for complete combustion. This air will take the path of least resistance though the fire, so if there are any thin spots, they will burn out the fastest and then allow the colder air to rush through that hole, thus pulling less air though the thicker parts of the fire where it is needed. If this problem is not attended to in time, the fire becomes very uneven, steam pressure drops rapidly, and the fireman's day suddenly becomes very miserable. Thus it is very important to keep the fire evenly distributed on the grates. We make the fire a bit thicker around the edges because that is where the air wants to come in first, and if a hole develops along the edge the cold air not only reduces the steaming capacity of the boiler, but the rapid cooling of the hot side sheets is very hard on the staybolts. Lastly, we add a small bank in the back corners because the grates are slanted forward, and the fire will have a tendency to slide down the grates and away from the back of the firebox.

I am often asked what is the "secret" of a successful fireman. There is no one secret to firing, other than the secret of knowing how to do a lot of things correctly. There are, however, a couple of keys to successful firing that I use. The first key is anticipation. A fireman should always be anticipating what the needs of the locomotive are going to be rather than waiting and reacting . For example, let's say we're running along with a fifteen car train on level grade at 50 mph, with a 1% grade three miles long coming up in five miles, with a 1% down grade on the other side of the hill. The fireman should be anticipating the change in steam needs and the change in the strength of the draft through the grates by preparing the fire so that it does not get sucked through the stack when the engine hits that grade. He will also work his water so that he has enough to make the extra steam to climb the grade, and to have a sufficient amount of water in the boiler so that when the locomotive tops over the grade, the water in the water glass will not plummet out of sight. If the fireman does not anticipate the upcoming grade and only reacts to the sudden change in steam pressure, he could already have a hole in his fire and not enough time to raise his water level to be able to keep water in the glass on the downgrade. Anticipation is the key.

The other key is learning to read the signs that the locomotive gives which tell you what its needs are, and to interpret them correctly. Learning to read the fire is probably the most critical. The fireman has to know whether a dark spot in the fire is due to too much coal, or no coal, or just unburned coal, or a clinker forming, or perhaps a restriction of air in the ashpan. He has to know whether a clear stack means he has perfect and complete combustion of his coal, or if he has a hole in his fire. If the fire is not burning evenly, is it because he is firing too heavily, or are the back corners lacking coal, or did the coal change from chunks to fines, or did the water from the rainstorm you ran though thirty miles back finally trickle down to the coal in the stoker screw, causing it to affect the distribution pattern? By incorrectly diagnosing a problem, a fireman can create a second problem when he makes the wrong adjustment. By reading the locomotive's needs correctly, the firemen's duties become much easier.

When running, I have a pattern of checkpoints which help me keep track of the locomotive's needs. I check the track ahead for signals, curves, grades, switches and obstructions. I check the color of the stack. Next the stoker gages for stoker speed and stoker jet pressure are noted. I check the water glass and make a mental note on how it has changed from the last check. The same is done with the steam pressure gage. Finally I check the stoker screw for speed, amount of coal, and quality of coal. The whole pattern then is repeated continuously while the locomotive is running. I will also do a periodic visual inspection of the firebox to check on the condition of the fire, as well as a boiler blowdown. If everything is going well, I have time to also wave to all the photographers along the right of way who I hope are generously supporting us with contributions so that we can continue to operate a locomotive that they can photograph!

This essay is not meant to be a comprehensive firing manual, but I hope it gives you some idea of how I approach the duties of a fireman on a steam locomotive. I would like to thank all of you who have helped us through your contributions and your support to continue to operate Milwaukee Road 261. We appreciate it very much. Together we can continue to pass on to the next generation a sense of what railroading was like when steam was king!

Firing Milwaukee Road 261