|£35,156 ($70.312)||112 km/h (70 mph)||207 t||6,600 hp (4,924 kW)|
|Running Costs / year||Designed||Lifespan||Capacity|
|£2,361 ($4.722)||1972||22 years||N/A|
The Centennial was an actual engine type, custom-built for the Union Pacific Railroad. Their name comes from the celebration of the 100th birthday of the Golden Spike.
The real life Centennials were designed to drive freight trains on the same line as Big Boy. Since Union Pacific started getting them in 1969, they got the name class 6900 as well as their manufactory name DDA40X. As if the locomotive didn't have enough names, an unofficial nickname is Big Boy 2 (not to be confused with the 2nd shipment of the real Big Boys, that also got called Big Boy 2 because of minor design changes) These engines are the largest diesel locomotive ever built with a weight of 270 tons (which was too much for TTD to handle, so it got lighter in the game). They consisted of a single frame (longest single frame engine ever built?) and was an amazingly 30 meters from coupler to coupler. Internally the engine is actually two locomotives, each with one V-16 diesel engine, which powers one bogie. This was not an uncommon design in the 1960s (or earlier for that matter), which made it possible to continue on one engine even though the other one is broken (another famous locomotive using this idea is the English Deltic). The locomotive had two bogies, each with 4 powered axles.
While this huge design gave the locomotive great power, it came at a price. The 4 axle bogies were hard on the track, specially in curves, where they pushed the rails to the sides, efficiently making the gauge wider (this is a common problem with steam locomotives as well). Since the leading bogie is always the hardest on the track (the next one gets pulled in the direction of the track by the first one), another smaller engine was often used in front of Centennials. The two diesel engines also meant that if one of them got problems, the whole engine had to be sent in for repairs (while two locomotives with one engine each can keep one in service while the other one is broken)
When technology around 1980 solved some of the problems regarding controlling multiple locomotives from one cab, the whole idea of having two engines on one frame to avoid using those systems died, and the Centennials were retired. Today only one of the 47 Centennials remain in service.