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Locomotive Niagara Class 4-8-4

Freight and Passenger Locomotive

Locomotive Niagara Class 4-8-4

The New York Central Railroad's speedway from New York to Chicago, was in steam days arguably the greatest passenger railway In the world, in terms of speeds run and tonnage moved. By the 1940s these speeds and loads were beginning to be as much as the famous Hudsons could cope with and the Central's chief of motive power, Paul Kiefer, decided to move on a step. He proposed a Niagara Class 4-8-4 with more than 30 percent greater adhesive weight and tractive effort than the 4-6-4, together with a fire grate 25 percent bigger. His aim was a locomotive which could develop 6,000hp in the cylinder for hour after hour and could do the New York-Chicago run day after day without respite.

Locomotive Niagara Class 4-8-4

The American Locomotive Company at Schenectady proposed what was to be the last really new design of passenger locomotive to be produced in the USA. It owed something to the Union Pacific's "800" class; dimensionally, the two designs were very close and, in addition, the design of the 14-wheel Centipede or 4-10-0 tender was certainly based on UP's. The NYC engines had something else unusual for North America, in common with the "800s"—a smooth and uncluttered appearance but with no false streamlining or air-smoothing.

TECHNICAL DATA
Origin: New York Central Railroad (NYC), USA.
Type: Express passenger steam locomotive.
Gauge: 4ft 8'/2in (1,435mm).
Propulsion: Coal fire with a grate area of 10sq ft (9.3m2) generating steam at 272psi (19.3kg/m2) in a fire-tube boiler, and supplying it via a superheater to two 25)4 * 32in (648 x 813mm) cylinders, driving the main wheels direct by means of connecting and coupling rods.
Weight: 274,000lb (124t) adhesive, 891,0001b (405t) total.
Axleload: 70,0001b (32t)
Overall length: 115ft 5y2in (35,192mm).
Tractive effort: 61,5701b (27,936kg).
Max speed: 80mph (128km/h).
Service entry: 1945.

Because the NYC structure gauge only allowed rolling stock to be 15ft 2in (4,623mm) high instead of 16ft 2in (4,928mm) as on the UP, the chimney had to be vestigial and the dome little but a manhole cover. There were other differences, such as Baker's valve gear instead of Walschaert's, but in general the adoption of standard American practice led to similarities. The foundation of the design was a cast steel integral locomotive frame-nothing else could have stood up to the punishment intended for' these engines. Also, as one might expect, all axles, coupling rods and connecting rods had roller bearings. Baker's valve gear has the advantage that it has no slides, so all its moving parts could, as in this case, be fitted with needle bearings. While speaking of the valves, an interesting detail was that the edges of the valve-ports were sharp on the steam side, but slightly rounded on the exhaust side. This eased the sharpness of the blast beats, thereby evening out the draught on the fire.

Although fundamentally of the same design as that fitted to the UP locos, the tender had some interesting differences. The fact that the NYC was one of the very few American railroads equipped with water troughs meant that less water could be carried, leaving more capacity for coal. This enabled the New York-Chicago run to be done with just one inter coaling, while an improved design of power-operated, pick-up scoop reduced delays by allowing water to be taken at 80mph (128km/h). Special extra venting avoided bursting the tenders (there had been cases!) when some 1,600cu ft (45m 3) of incompressible fluid entered the tank all in a few seconds. Incidentally, the overhang of the tank at the rear was to allow the engines to be turned on 100ft turntables by reducing the wheelbase.

Allocating the number 6000 to a locomotive whose target was that amount of horsepower as well as that number of miles run per week might seem to be tempting providence, but all was well. The prototype had the sub-class designation "Sla", while the 25 production models (Nos. 6001- 6025) were known as "Sib", and there was also a single poppet-valve version known as "Sic" (No. 5500). This greatest of steam locomotives got the class-name "Niagara" and when the word is uttered, no steam man worthy of the name ever thinks of a waterfall!. Both targets were achieved —6,700hp on test and an average of 26,000 miles run monthly. The original idea was that the prototype should be tested and then a production order confirmed, but before work had gone very far instructions were given for all 27 to be put in hand. This was reasonable because in fact the "Niagaras" were very much a standard, if slightly stretched, product of the industry, whereas what really needed attention was the ground organisation to enable the mileage target to be met. And this, of course, could not be tested until a fleet was available. By an ordinance of the City of New York, steam locomotives were not allowed inside city limits. Trains therefore left Grand Central Station behind third-rail electric locos for Harmon, 32 miles out in the suburbs. It was here, then, and at Chicago that the "Niagaras" were, in their great days, kept in first-class condition for what was without doubt one of the hardest services ever demanded of steam, or for that matter, of any motive power.

World records are not achieved without extreme efforts, but excellent organisation allowed quick and thorough servicing. The power production part of the locomotives had to be just-so to give such a remarkable performance out on the road, and to achieve this the fire was first dropped with the engine in steam. Then a gang of "hot men" in asbestos suits entered the firebox-the size of a room-and cleared tubes and flues, and did repairs to the brick arch and grate. Good water treatment ensured that no scale built up in the heating surface, preventing the heat reaching the water inside the boiler. On many railways steam locomotives were allocated one "shed day" each week for these things to be done, but running the 928 miles (1,493km) from Harmon to Chicago or vice versa each night, the "Niagaras" needed to do a week's work in one 24-hour period.

In those days there were 12 daily trains each way just between New York and Chicago-the "Chicagoan", the "Advance Commodore Vanderbilt", the "Commodore Vanderbilt", the "Advance Empire State Express", the "Empire Express", the "Lake Shore Limited", the "Mohawk", the "North Shore Limited", the "Pacemaker", the "Water Level", the "Wolverine" and, the greatest of all, the 16 hour "Twentieth Century Limited". Even the most fanatical steam enthusiast would admit that other factors have contributed, but nevertheless the Day of the "Niagaras" did mark a peak. The best time by diesel traction today on this route between New York and Chicago is 16hr 50min and there is only one train.

The "Niagaras" also demonstrated once again that modern well- maintained steam power could be more economical than diesel. Alas, in those days, coal supplies controlled by miners' leader John L. Lewis were less reliable than oil supplies; moreover, most of New York Central's steam power was neither modern nor well-maintained. So, having run more miles and hauled more tons in their short lives than most locomotives which run out their term to obsolescence, the "Niagaras" went to their long home. None has been preserved.

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