HSR and grades

Thought a visual representation would be apropos. This would be the Rhein-Main high-speed line in Germany — built alongside the Autobahn to minimize impact on the environment.

The road and rail line are very foreshortened from the picture's view direction. It would be more reasonable to have a side view of it.

Which German high-speed-rail line is this? One of them, the Cologne-Frankfurt line, has a maximum grade of 4%, which is high by railroad standards.

lpetrich wrote:Which German high-speed-rail line is this?

The original poster indicated that it is the Köln Rhein-Main NBS.

the hey to been able to have steep grades would be light weight of the trainsets .
on the original tgv lines , they actually had to slow the trains as they reached the crest of steep grades to avoid them taking off .

David Benton wrote:the key to being able to have steep grades would be light weight of the trainsets .
on the original tgv lines , they actually had to slow the trains as they reached the crest of steep grades to avoid them taking off .

Light weight is necessary for high speed. The Americans are going to have to face this and solve the problem. Their current trains are far too heavy, and must use much more energy than European trains.

It is also necessary for other trains. There are many short lines that could be successful if they had light weight European designs, which can never be a success with dinosaurs.

Light weight is necessary for high speed

No, it really is not. Recall that the ICE 1 was almost as heavy as the Acela Express in terms of individual cars, the latter not being a high-speed train per se anyhow (but the former was built to operate at 175 mph, which it has done for several years).

Also, the lighter ICE 3 and ICE-T have been taken out of service due to wheel problems. (Besides, the 16-car ICE 3 trains were using quite a lot of energy in and of themselves; on top of that, the voltage and frequency of Germany's rail electrification is stepped down from commercial.)

What's necessary for high speed is building of infrastructure for support of such operations. So far, the USA has built nothing. The picture in the original post is exemplary of what Germany has.

PullmanCo wrote:

No, it really is not. Recall that the ICE 1 was almost as heavy as the Acela Express in terms of individual cars, the latter not being a high-speed train per se anyhow (but the former was built to operate at 175 mph, which it has done for several years).

Yes, it is. The ICE is nowhere near as heavy as the Acela, it's 849 tons for a 12 car train vs 566 for a 6 car Acela. The individual cars aren't as heavy either - 120,000 lbs max on the ICE vs 125,000 and up on the Acela. The Acela's powercars are also far far heavier, roughtly 100 tons vs 75 or so for the ICE.

The ICE is also much heavier than the TGV. It's not that the Germans don't understand light weight - some of their DMUs have curve speeds that make the Acela's attempts at rounding curves look like a bad joke, but axle loading is so critical that the cars must be weighed en-route. But light axle loading is required for high curve speeds (which is why the Talgo exists), and has the bonus of greatly cutting track wear (which on most euro HS lines isn't any higher than a conventional line).

You'll also note that the next generation HSTs all feature reduced axle loadings and lighter weight, at considerable R&D cost.

Also, the lighter ICE 3 and ICE-T have been taken out of service due to wheel problems. (Besides, the 16-car ICE 3 trains were using quite a lot of energy in and of themselves; on top of that, the voltage and frequency of Germany's rail electrification is stepped down from commercial.)

And the Acela's been sidelined a few times due to cracks and suspension issues, etc. Germany has such an extensive 16 2/3rd Hz system that they have a number of dedicated generation stations (I believe one nuclear, even), and a large distribution network at high voltage. Every rail system in the world steps their voltage down from transmission levels because electricity is transmitted at 100,000+ volts and catenary voltages are at most 50kv, and generally 30kv and less.

What's necessary for high speed is building of infrastructure for support of such operations. So far, the USA has built nothing. The picture in the original post is exemplary of what Germany has.

Conventional track in Germany is maintained to a higher standard than the '150mph' segments in the US are.

But nonetheless, you simply need light weight to go fast. RR engineers at JR, SNCF, SJ, SF, DB, SBB, etc all agree on this - it's only the FRA/Amtrak, who's 'high speed' experience consists of running a single electric line (the NEC) at conventional speeds (100-125mph), that disagrees. There are probably single trains in SNCF's TGV fleet that have more time at 125+ than all the Acelas combined...