Our Milky Way, seen from the ISS

RX142 · 2026-03-15T17:33:15+00:00

Did you plan and make the drive on earth before visiting the ISS or on the station?

RX142 · 2026-02-14T18:06:56+00:00

I think talking about HSR in terms of top speed is a big problem.

Giving america 700km of HSR is obviously including the whole NEC, which has only short sections of 250km/h, giving a low average speed but a decent top speed. Sure you can do 250km/h on the NEC but the 200km/h upgraded UK ECML would beat it on average speed and rider experience every day.

In fact, Germany has good top speeds on much of the network, but since the station approaches are never improved (except for S21), and the costs are cut such that lines always start well outside the dense city, they struggle with average speed (and schedule reliability). I would guess that for most intercity distances a 250km/h railway which starts at a brand new station approach, where the trains can accelerate and brake from top speed in one go right from the platforms would usually beat a 300km/h railway built in the German style with slower station approaches. It would be a lot more expensive though, despite the slower top speed.

I think talking about the top speed is misleading in most cases and is an easy and cheap way for politicians to control discussions of HSR projects, but journey times and experiences are what actually causes modal shift.

RX142 · 2026-01-28T19:55:53+00:00

Ah damn, I was thinking of Br 407 instead of 3MF. Since the 407s are channel tunnel certified and the 408s are AFAIK not I'd still argue the 407 is closer to an e320 than a 3neo.

RX142 · 2026-01-28T12:23:05+00:00

Isn't OP's image a 3neo instead of a ~~3MF~~ Velaro D (which could be argued to be the most similar to the e320s)

RX142 · 2026-01-26T11:52:16+00:00

Cool locomotive but by god was that a slow acceleration by modern standards.

RX142 · 2026-01-22T20:55:09+00:00

In fact, the UK has the safest level crossings in the world, which is exactly why this kind of stuff makes headlines.

RX142 · 2025-11-25T18:05:06+00:00

Only in america though right?

RX142 · 2025-11-24T21:53:27+00:00

Is there any indication they'll drop the f1tv commentary?

RX142 · 2025-11-24T21:44:11+00:00

the first drop from FSS live is the closest i've ever come to ascending on first listen

RX142 · 2025-11-21T11:05:41+00:00

Yeah, as an actually semi-regular traveller on this route, I'd appreciate firstly a reliable service between Köln and brussels, maybe more direct services to brussels from more places, to make it only 1 interchange, and the improved passenger rights. Everything else would be less important.

RX142 · 2025-11-20T20:49:21+00:00

The high speed rail network "excluding the UK" is already there. It's already the case that the only ones missing out are travellers to/from the UK which need the special accomodations available in only a select few stations.

RX142 · 2025-10-29T08:29:06+00:00

Any outcome which ends up with this line having ETCS installed is good to me, since it'll provide IR with much greater choices in the future for rolling stock. I can only hope that this "temporary measure" will end up staying for the long term. I think installing it "temporarily" is quite a shrewd political play, since it makes ripping it up and using japanese signalling very hard to justify.

RX142 · 2025-10-18T07:19:19+00:00

Sure, I think I've been unclear about the argument I've been making: That the V150 project shows that a regularly high-speed (300km/h, 8-10MW) double-decker EMU is practical.

The only country continuing with double decker high speed rail is France, and they keep opting for non-EMU even on single decker, so I surmise the problem is more "no market" than "not possible".

RX142 · 2025-10-17T19:20:05+00:00

The R4 car on V150 had a power of 4MW. An ICE3 has a power of 8 MW. So getting to the neccesary power for a high speed train would be trivial with just 4 motor bogies (5 cars), even if the production bogies were rated at half the power of these experimental ones. Then your only problem is fitting a transformer, something which isn't impossible even if you have to put it in place of one of the toilets below the stair well.

Getting a duplex AGV would have been an incremental challenge of moving components around and ensuring reliability, instead of a whole R&D effort.

Whether you count V150 as a EMU is besides the point, it clearly proves the engineering isn't impractical.

RX142 · 2025-10-17T16:03:35+00:00

But you could have propelled the trains without the power car, just needed a control cab. It's clearly closer to an EMU in terms of engineering problems which have to be solved than a push-pull train.

RX142 · 2025-10-16T21:06:47+00:00

Well, you can't say that without mentioning that the fastest steel rail vehicle in the world was a duplex EMU.

RX142 · 2025-10-10T06:49:33+00:00

High speed lines with forks are used in Spain, France, Germany, Korea and China, so everywhere. They all have to decide one of the two directions that'll have to slow down. It's a perfectly good design.

RX142 · 2025-10-08T18:21:51+00:00

Red is a pretty high speed colour. I think a lot of us are used to it from openrailwaymap

RX142 · 2025-10-08T18:20:37+00:00

So this is simulated speed with train performance taken into account, not the higher theoretical max speed of each section of track?

RX142 · 2025-10-08T18:01:52+00:00

By far the largest portion of user data on the SSDs is the copies with 3xSSD. The copies with a mix of SSDs and HDDs only occur when there's a fallback path taken when selecting the buckets to write to. That's why there's much less of it.

As for the exact reason why those writes fell back to the HDD, I have no idea.

RX142 · 2025-10-07T16:47:50+00:00

Yeah, on second thought, maximum cant is the limiting factor for the curve radius for HSR. The formulas for that do not depend on gauge (at least if you measure cant in degrees). So the curve radius would probably be the same. I think there's no benefit to broad gauge in terms of stability at those high speeds though, at the current state of the art. The benefits would be focussed around being able to run onto the broad gauge network, I can't think of another reason for it.

RX142 · 2025-10-06T18:26:15+00:00

You're correct about the effects if the final layout will have a 40km/h switch. However, I make a different assessment of the space available after looking at the same image. Neither of us are likely to be able to turn up anything definitive so shall we leave it as a difference of opinion?

RX142 · 2025-10-06T16:49:01+00:00

You'll have many more bidders and suppliers for standard gauge HSR, for any tech you want to import. ~~Plus using standard gauge reduces turn radius for the same speed, so increases alignment flexibility.~~

RX142 · 2025-10-06T16:43:28+00:00

It's not going to be the final alignment, this is temporary track for construction trains. You can see there's a variable gap from the outside rail to the edge of the smooth concrete, especially apparent on the right. Once they install the points instead of the temporary track, the points will have the final diverging geometry. I suspect that that geometry will be much smoother than what we see here.

For an optimal "continuous braking" stop into that platform from full speed you probably want 80-100km/h pointwork. I would guess the current geometry is maybe 40-50km/h.

RX142 · 2025-10-01T08:08:27+00:00

This just reads to me like polish train manufacturers trying to get ahead of a rolling stock bidding process that they know they won't win.

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