Example trains used for calculation
Working with the results of the last page, the following high-performance loco is identified to be a realistic setup, within the restrictions of FRA regulation:
- 80 tons, or very few tons more.
- 9 or 10 inches unbalanced superelevation allowed for tight curvature.
- 3500 - 3800 hp.
The Spanish 354 still needed to use 2 motors in 1984. Today, 3500 - 3800 hp are easily delivered out of one high performance diesel. There are at least 6 options available:
|power @ speed||mass (dry)||www data sheet
|Cummins QSK78-L||3500 hp (2610 kW) @ 1900 rpm||9.9 tons (8950 kg)||no
|MTU 20V 4000 R42||3621 hp (2700 kW) @ 1800 rpm||9.3 tons (8430 kg)||yes
|Detroit Diesel 20V 4000 R42||similar||data||no
|Pielstick 16 PA4 V 200 VG||3540 hp (2640 kW) @ 1500 rpm||11.0 tons (10000 kg)||yes
|MAN B&W Paxman VP185 18V||3753 hp (2800 kW) @ 1500 rpm||11.2 tons (10160 kg)||yes
|MAN B&W Paxman VP185 18V||4157 hp (3100 kW) @ 1800 rpm||11.2 tons (10160 kg)||yes
The European Talgo locos achieve their low weight with hydraulic transmissions. Weight of the currently developed hydraulic transmission "Voith LS 640 reU2 + KB 360", which allows up to 5029 hp, will be 7.7 tons. The dynamic brake is integrated, and included into the weight figure. At the moment, this is the most realistic option for a lightweight high performance loco. Given the progress in AC technology, electric transmission might be an option in near future.
While hundreds of 125 mph push-pull intercity trains are used every day in other countries, the author expects regulatory problems in the USA. For this reason, it is suggested to use end cars for hotel power generation. This has been the standard setup of older Talgos in Europe. Since the FRA dislikes lightweight cab cars with passengers, a power car with cab is suggested for trains with one loco, replacing the lightweight cab car offered in Europe by Talgo. All the loco power can be used for traction in such a setup, and freight locos can be used as emergency power.
Two example Talgo trains will be created on this page, and travel time calculations for the Shasta Route will be based on their performance. For the reader, this allows to check, wether assumptions of the author are realistic. Assumptions are decisive for the results of such calculations. Only one difference will be made between day- and nighttrains: For unbalanced superelevation, a maximum of 7 inches is assumed while traveling deep in the night. Talgo has already delivered all types of both luxury and basic overnight cars, so there is no reason to assume a different train type.
The following table will define a half length push-pull set with one loco and a cab car, plus a full length push-pull set with one loco at each end. Listed are maximum configurations within the power-to-weight limits.