Brightline Orlando extension

[jis]

And expensive electrification to actually operating at 160.

 

[Tlcooper44]

On a completely different thought wave...

The section between Cocoa and MCO .will be class 7 trackage with a max speed of 125 mph. Why didn't they go for true HSR and build to class 8? I know the real answer is money, but what are the physical challenges to jump to the next level of 160 mph operations?

In the places that can accommodate class 8, does it make sense to? Would it really effect journey time all that much, especially since the tracks aren’t electrified? Not sure diesels can achieve 160 to begin with.

 

[Qapla]

How long does it take for a train like this to accelerate to 160? On the trip from Cocoa to MCO, would there be any stops? Is that entire distance straight enough 160 operation the whole way?

Since it is only about 39± miles between Cocoa and MCO (according to the distance stated by looking online) the time savings would total about 4 minutes (according to the travel time calculator I used) if you could travel at maximum speed the entire distance (savings would be less if you stopped along the way or had to slow down from the 160 mph) - would it even be worth the added expense for that small distance ...

 

[west point]

Yes diesels could do 160. It would take higher gear ratios for traction motors and much more loco power.

 

[joelkfla]

Yes diesels could do 160. It would take higher gear ratios for traction motors and much more loco power.

But are they, or are you just speaking in theory? I thought 125 was the current operating limit.

 

[cirdan]

In the places that can accommodate class 8, does it make sense to? Would it really effect journey time all that much, especially since the tracks aren’t electrified? Not sure diesels can achieve 160 to begin with.

But how about just future-proofing? This can consist of choosing the alignment and curvatures in such a way as to allow higher speeds later. When you build, those things may marginally add to costs. When you want to fix them retroactively they cost much much more.

 

[cirdan]

In the places that can accommodate class 8, does it make sense to? Would it really effect journey time all that much, especially since the tracks aren’t electrified? Not sure diesels can achieve 160 to begin with.

I guess nothing is impossible, but it may be unviable.

The speed record for a diesel passenger train is AFAIK still the British HST which did mid-140mph speeds on various test runs, both as a prototype in the early 1970s and using standard sets on further test runs in the mid 1980s. And remember these were test runs, well prepared, planned and monitored. The same trains were limited to 125mph commercially.

I guess the technology has advanced since then. And maybe using underfloor distributed traction on a DMU (a bit like the diesel ICE) may allow better speeds. But it's still a huge leap to 160.

 

[user 1215]

Amtrak is literally spending millions to try and squeeze 5 MPH here and there along the NEC to save seconds. Granted, they are already electrified.

 

[jis]

Cocoa to Orlando between the end of the Cocoa Curve and Henzelman Blvd. will be pretty flat out 125mph. Increasing to 160mph will cost a very large sum of additional money and will gain maybe 4 minutes realistically. Given how difficult and torturous it was for them to get the funding for doing what they are doing, I don;t see how realistic even an attempt to get additional funds are at this point.

And I am curious, what is so special about 160mph in open new construction? NEC has that limit because of reduced track center distance which is very very expensive to fix. Why not 186 (300kph) or 200 (320kph)?

 

[Caesar La Rock]

There are some downs to electrifying as some have pointed out, but there is some positives. At least the whole system will be new compared to the NEC and there won't be the amount of restrictions that limits speed on the line. Plus it would make everyone happy with transportation going "Green", diesel fuel ain't getting cheaper people. With that said, why not shoot for speeds higher then 160? There is one issue with that idea, is 125mph the fastest the Venture cars can go or can they go much faster then that? I would imagine, newer trainsets capable of higher speeds would need to be ordered if Brightline ever went in that direction.

 

[joelkfla]

diesel fuel ain't getting cheaper people

As I understand it, a diesel-electric is really a self-contained mobile generator. Perhaps in 10 years, something better will come along that also doesn't require the expense and ugliness of catenary. Who would have thought 10 years ago that we'd now have fully battery powered buses and streetcars?

 

[jis]

. At least the whole system will be new compared to the NEC and there won't be the amount of restrictions that limits speed on the line.

A system running 24 trains a day will be compared to the NEC? Really? You do realize that currently a significant portion is also being built with single track, which can be expanded to two tracks in the future. And the higher speed portion is only th 35 or so miles from Cocoa to OIA. The speed between Miami and Cocoa will never rise above 110mph - because - grade crossings, figuratively speaking, hundreds of them.

 

[cirdan]

As I understand it, a diesel-electric is really a self-contained mobile generator. Perhaps in 10 years, something better will come along that also doesn't require the expense and ugliness of catenary. Who would have thought 10 years ago that we'd now have fully battery powered buses and streetcars?

maybe, who know?

IMHO the whole point of electric trains is that you save on weight, so no heavy generator set or battery packs to lug around, so all that power translates directly into acceleration. Thus the power source needs to be externalized. I believe battery streetcars are used mostly for architectural reasons when putting up catenaries might mean unacceptably disfiguring historic or beautiful locations. I don't think they are actually cheaper than electrification, except maybe in some special cases. This can still evolve of course. But I think there is also still potential to bring down the costs of electrification as many systems are over-designed. This may have to do with legacy systems versus all new systems that can be planned from scratch and use a small number of highly standardized parts and don't need to be reverse compatible to something from the 1930s.

 

[NES28]

125 mph is the practical limit for diesel operation, worldwide. Electrification is required to go faster.

 

[Tlcooper44]

For Florida and the transportation situation there, I don’t think it’s necesary for the train to operate any faster in order for it to compete well against other forms of travel. 4 minutes is not enough time to justify millions.

It’s a working theory of mine, but I don’t think there are too many cases around the world where true HSR is required to get the benefits “fast, frequent, and reliable trains.”

 

[Caesar La Rock]

A system running 24 trains a day will be compared to the NEC? Really? You do realize that currently a significant portion is also being built with single track, which can be expanded to two tracks in the future. And the higher speed portion is only th 35 or so miles from Cocoa to OIA. The speed between Miami and Cocoa will never rise above 110mph - because - grade crossings, figuratively speaking, hundreds of them.

You do realize my post was a what if situation where Brightline did electrify its route from Miami to Orlando. That's why I made the comparison between Brightline's route to the NEC, because there wouldn't be as many obstacles preventing Brightline trains from reaching and maintaining the max speed of the route. As for that higher speed section, I'm clearly aware of that by the videos I've been watching of the construction the past few months and what's been documented, so far. Also knew about the grade crossings between Miami and Cocoa, but once again a what if scenario vs. what's already planned out now. Also in response to the negatives and positives of electrification.

 

[jis]

You do realize my post was a what if situation where Brightline did electrify its route from Miami to Orlando. That's why I made the comparison between Brightline's route to the NEC, because there wouldn't be as many obstacles preventing Brightline trains from reaching and maintaining the max speed of the route. As for that higher speed section, I'm clearly aware of that by the videos I've been watching of the construction the past few months and what's been documented, so far. Also knew about the grade crossings between Miami and Cocoa, but once again a what if scenario vs. what's already planned out now.

No I missed that. Thanks for clarifying.

Still I don't believe Brightline will ever get the traffic the combined Amtrak and Commuter traffic has on the NEC.

And the dream of a hypothetical no grade crossing on the FECR segment at best will probably at least as much money as fixing up the NEC. And all you get is 8-12 minutes out of it. Is it worth it? But yeah good thing to dream about from a distance And Brightline has to figure out how to recoup all that from marginal revenue for 8-12 mins.

Frankly if between Florida and the Feds that kind of money and requisite political will becomes available it would be much better spent on a new West Coast Line from Tampa to Fort Myers with extension to the North through the Village to Ocala and Gainesville onto JAX

 

[Qapla]

Frankly of between Florida and the Feds that kind o0f available it would be much better spent on a new West Coast Line from Tampa to Fort Myers with extension to the North through the Village to Ocala and Gainesville onto JAX

 

[George Harris]

Saying all this from the perspective of a Civil Engineer that has spent most of his working life on railway projects from streetcar to high speed:
1. There is nothing inherent in a diesel that prevents speeds above 125 mph. As noted, a diesel is primarily an electric locomotive carrying around its own source of electricity.
2. Weight on powered axles is significant not just in starting, but as speed increases, adhesion decreases. That a major reason that EMU setups are the norm in very high speed operations. Once you have passed the adhesion limits additional power does absolutely nothing for you. Think operation in heavy rains in Florida.
3. Unnecessary weight is more significant in acceleration and braking than in constant speed running, so with long distances between stops a diesel-electric is not that great a penalty.
4. Design for higher speed than initial operating speed, or even than what you think to be your highest speed ever. Overdesign particularly for curve radii, spiral lengths, and vertical curve lengths. Designing for the curve superelevation you need for the fastest ever speed does not mean you have to build it with that much superelevation to begin with. Superelevation can be increased relatively easily if the curve radii and spiral lengths allow for it.
5. Multiple grade crossing issues can be solved by changing the railroad's track elevation. In the case of Florida, the logical thing would be to elevate the line. This solves several other issues, as well, such as trespassers, utility crossings, restrictions in cross right of way movement, etc. (By the way, anyone suggesting tunneling or lowering the railroad to allow the streets to remain at their current elevation, does not live in the real world as it is in south Florida.)

At this point, the speed of 300 to 350 km/hr (186 to 220 mph) seems to be approaching the practical limit for several aspects of railroad operation, including the decreasing adhesion with grade curve meeting the increasing power, which equals increasing adhesion required to balance aerodynamic resistance.

One thing you don't have to worry about on a high speed railway, which is also a non-existent issue in Florida anyway, is downgrade runaways on a 220 mph railroad. When you design for comfort at 220 mph, aerodynamic resistance will keep the train speed below the probably derailing speed. Of course you could probably manage it if you applied power to the max while going downgrade, but that is the same mindset that causes people to fly planes into buildings, and with an electrified railway, that can be stopped by simply shutting down the catenary for that part of the line.,

 

[cirdan]

It’s a working theory of mine, but I don’t think there are too many cases around the world where true HSR is required to get the benefits “fast, frequent, and reliable trains.”

I think it depends on who the train is competing against and also the distance covered.

If you're competing mainly against buses and people driving their own cars, 125mph is mostly fine. It's still not necessarily faster than driving of course because you need to factor the time to get to the station plus the inconvenience of a scheduled service versus being able to drive when it suits you.

Thus I believe that as important as the speed itself is, locating the stations wisely and in a way that maximizes accessibility for as many people as possible. I think many of the newer HSR lines in Europe made errors in this respect, with some stations located in rather pointless locations and much of the speed advantage of the train being negated in getting there in the first place.

On commuter-oriented services, much lowers speeds can still be competitive because commuters typically travel at peak times when roads are congested and driving takes a long time.

In addition you need to factor in the value of the time. So on a train you can do some work on the laptop or just relax or read the news or look out of the window, which is typically a higher quality use of time than being concentrated on the traffic around you.

When it comes to competing against airlines, speed is important. Flying may be faster from point to point but when you factor in time needed for checking in and security and other such things, trains may be able to steal an advantage on shorter haul routes. And this does not even require 125mph running. British Rail was already seriously hurting domestic flights between London and Manchester as early as the 1970s, and at this time the trains had 100mph top speed. Not yet 125mph. But this was done using a frequent service using comfortable modern trains.

But when it comes to slightly longer distances, you need to go faster than that to compete against airlines. Prior to the opening of the AVE, Barcelona to Madrid was aver 5 hours (from memory). And although the Talgo trains used at the time were comfortable, the airlines had the lion's share of the market. It took HSR taking journey times down to 2 hours and 30 minutes to reverse that trend.

 

[toddinde]

For Florida and the transportation situation there, I don’t think it’s necesary for the train to operate any faster in order for it to compete well against other forms of travel. 4 minutes is not enough time to justify millions.

It’s a working theory of mine, but I don’t think there are too many cases around the world where true HSR is required to get the benefits “fast, frequent, and reliable trains.”

I completely agree. Train speeds don’t only come from the top end. You can squeeze more time savings from taking 30 mph track and making it 50, and 59 mph track and making it 79 where that can be done. You also correctly point out that speed isn’t really that important. High speed rail has disadvantages too. If it bypasses lots of stops, you lose time going from the terminal to your destination. A conventional speed train making suburban stops may actually save time over a limited stop, high speed train. Reliable, speedy, conventional trains with adequate frequencies, and pleasant onboard amenities will pack more bang for the buck in most corridors.

 

[jis]

I completely agree. Train speeds don’t only come from the top end. You can squeeze more time savings from taking 30 mph track and making it 50, and 59 mph track and making it 79 where that can be done. You also correctly point out that speed isn’t really that important. High speed rail has disadvantages too. If it bypasses lots of stops, you lose time going from the terminal to your destination. A conventional speed train making suburban stops may actually save time over a limited stop, high speed train. Reliable, speedy, conventional trains with adequate frequencies, and pleasant onboard amenities will pack more bang for the buck in most corridors.

I agree wholly. If more money becomes available I would use it for serving additional corridors even if it takes building new trackage on new ROW, instead of trying to jack up speeds beyond 125mph. What we need to have first is to serve more unserved places first.

I believe in Florida Brightline is really trying to be more in the "conventional train with adequate frequencies and pleasant onboard amenities" rather than trying to win speed awards. Brightline West is a different matter altogether. Of course because this is the USA people don't think of 125mph trains as "conventional trains", due to the backwardness inherent in the local experience.

 

[cirdan]

Amtrak is literally spending millions to try and squeeze 5 MPH here and there along the NEC to save seconds. Granted, they are already electrified.

In railroad terms, millions are small change. Big projects such as HSR cost billions.

 

[user 1215]

And expensive electrification to actually operating at 160.

JetTrain

 

[user 1215]

And the dream of a hypothetical no grade crossing on the FECR segment at best will probably at least as much money as fixing up the NEC. And all you get is 8-12 minutes out of it. Is it worth it? But yeah good thing to dream about from a distance And Brightline has to figure out how to recoup all that from marginal revenue for 8-12 mins.

Even if you could get rid of all the grade crossings (my first thought is elevated track from Miami to Cocoa), you will never get rid of all the draw bridges.