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  • Brightline West (XpressWest, DesertXpress) Las Vegas - Victorville - Rancho Cucamanga - LA Proposal

  • This is a forum for all operations, both current and planned, of Brightline, formerly All Aboard Florida and Virgin Trains USA:
    Websites: Current Brightline
    Virgin USA
    Virgin UK
This is a forum for all operations, both current and planned, of Brightline, formerly All Aboard Florida and Virgin Trains USA:
Websites: Current Brightline
Virgin USA
Virgin UK

Moderator: CRail

 #608061  by Chafford1
 
Until recently, the DesertXpress project from Victorville to Las Vegas planned to use 125mph diesel trains (the UK Bombardier Meridian trains) for their project. However the website now talks about 150mph self-powered trains which will be a world first for commercial service at that speed - the official Guinness world record for a diesel train is 149mph!!

http://www.desertxpress.com/technology.php
Last edited by Jeff Smith on Mon Nov 05, 2018 4:30 pm, edited 3 times in total.
 #608200  by george matthews
 
I don't believe a diesel can do 150 mph. "Self-propelled" is an ambiguous expression. It suggests an electric motor in each carriage. Also that suggests either an electric train or a diesel-electric. The picture is just an advertiser's idealisation.

The background on some pages is clearly a Eurostar.
 #608332  by lpetrich
 
DesertXpress will utilize proven, off-the-shelf European steel wheel on rail high-speed trains, customized for the unique setting of the corridor.
The illustration in the Technology page shows a rather generic high-speed trainset with a pantograph and an overhead cable, though that pantograph and cable look like they are behind the train.

Since most European high-speed trains are electric, does this mean that the DesertXPress planners have shifted from diesel to electric?

There's also the question of FRA compliance. Perhaps the success of California's Proposition 1A has emboldened the DesertXPress planners to consider non-FRA-compliant transets, which is logical for a route that has no other trains on it.
Train interiors will be configured to maximize entertainment and passenger comfort.
Will it have what some airlines now have -- flat-panel displays on the backs of seats?
Each car will be self-propelled to provide the high power-to-weight ratio needed to follow the I-15 alignment and negotiate its relatively steep grades through two desert mountain passes.
So it must be either an EMU or a DMU trainset, and from the recent illustration, likely the former. Some high-speed-train designs are indeed EMU, like the Siemens ICE3 / Velaro, the TGV's successor, the AGV, and the Pendolino ETRs.
DesertXpress will operate at a top speed of 150 mph, making the 190-mile trip in about 1 hour and 20 minutes, like clock work, no matter what time of day, every day of the year.
Given the track record of high-speed trains, that's achievable as long as it has its own tracks.

The DesertXPress planners are still thinking of Victorville - Las Vegas, though they concede that they could connect to Palmdale or cross Cajon Pass to the Inland Empire and Los Angeles. Still no mention of bus connections at the Victorville end, however.
 #608519  by amtrakowitz
 
Hey, waitasec. 190 miles in 1 hour 20 minutes is an average speed of 142 miles per hour. If your top speed is going to be 150 mph, you're going to have to have acceleration like a bat out of Hades. :-D Even Shinkansen non-stop expresses need to run at 186 mph to get an average speed of around 142 mph, IINM.
george matthews wrote:I don't believe a diesel can do 150 mph
Why not? Enough horsepower (with power to weight ratio considerations) and the right gearing and there's no reason it can't. The Talgo XXI hit 152 mph during its tests.
 #608579  by Matt Johnson
 
I think the Turboliners are still for sale! ;) Seriously, does this group have any credibility? I've never heard of it. Anyone can put together a website. Getting actual funding is another matter.
 #608604  by george matthews
 
Matt Johnson wrote:I think the Turboliners are still for sale! ;) Seriously, does this group have any credibility? I've never heard of it. Anyone can put together a website. Getting actual funding is another matter.
I don't really understand why anyone would want to go to Las Vegas, but clearly people do. Nor do I think Las Vegas is a good thing as a huge waster of water and energy.
Turbotrains are also huge wasters of energy. The whole concept is dead. Cut them up or electrify them.
 #608788  by amtrakowitz
 
Turbotrains are also huge wasters of energy. The whole concept is dead. Cut them up
IINM, all the UAC Turbotrains are already cut up. I don't remember any of them being saved. Pity, too, because their ability to hit 170 mph would make the run faster and of course more economical (no stops).

AAMOF, the RTL Turboliners might be ideal for this service. Victorville to LV, no stops? Perfect scenario for constant-speed running of the gas turbine :-D Why wait? NJT didn't want 'em for their ACES service, after all :-) plus on the DesertXpress you have dedicated ROW (less to zero FRA interference), compatibility with both low and high platforms (so you can build whatever kind of platform you want), ability to use Number 2 fuel oil (same as diesels burn), and so on and so forth...
 #609214  by lpetrich
 
As to acceleration performance, here is some mathematics:

For constant acceleration a over time t, the velocity is:
v = a*t

and the distance covered is
l = (1/2)*a*t^2

The distance and velocity are thus interrelated by
l = v^2/(2*a)

We can now find how much extra time is consumed by accelerating and breaking, as compared to traversing the distance at top speed.
t(top_speed) = l/v = v/(2*a)
t(accel) = v/a
t(accel) - t(top_speed) = v/(2*a)
The acceleration time itself.

As a reference, I will calculate the distance and time to accelerate to 100 km/hr at 1 g (9.81 m/s^2) acceleration. They are:
distance = 39.3 m
time = 2.83 s

From Passenger Equipment Safety Standards, the TGV lateral-acceleration limit is 0.12 g, and I will use that figure for the travel-direction acceleration.

Using this acceleration and the DesertXPress's cruising speed, 150 mph / 240 kmh, yields
distance = 1.89 km / 1.2 mi
time = 56.6 s

But from http://www.dsy.hu/thermo/pub13/p_bremond.htm]Infrared characterization on thermal gradients on disc brakes, I find a braking distance of 3500 m from a velocity of 300 km/hr; this corresponds to an acceleration of 0.1 g and a stopping time of 83.3 s.

So the DesertXPress will take 1 extra minute to accelerate and 1 extra minute to brake relative to its full-speed time.

-

I then looked for a benchmark of real-world high-speed-train performance. I chose Paris-Lyon TGV because it is nonstop and relatively long. Checking on RailEurope, the scheduled travel time between Paris's Gare de Lyon and Lyon's Saint-Exupery station is 1h 54m.

Using Google Maps to estimate the line's distance by planning a flat-road trip between those two stations, I find 486 km / 302 mi. Doing that for Google's canonical city centers, I find 466 km / 289 mi. The great-circle distance between the two stations is 403 km / 250 mi, which is about 1/6 shorter, because both the highway route and the TGV line (LGV) bend toward Dijon. According to Wikipedia's article LGV Sud-Est, it is 425 km / 264 mi long, halfway between the flat-road and the great-circle distances.

The Paris-Lyon TGV thus travels with an average speed of 224 kmh / 139 mph, which is about 75% of its maximum speed of 300 kmh / 186 mph.

By comparison, the projected Vic-LV travel time of 1h 20m over 190 mi yields an average speed of 142 mph, which is very close to the Paris-Lyon-TGV average speed.

So if the Vic-LV line has performance handicaps similar to the Paris-Lyon LGV's, then it will require trains with a maximum speed of 300 kmh / 186 mph.

This rules out even the fastest diesel trainsets now in service.
 #609357  by amtrakowitz
 
Hmm. Pretty good analysis, but you might want to compare the Shinkansen, since, in a technical sense, the DesertXpress is going to be more like it in terms of using its own right of way. The TGV runs on traditional rails for a certain portion of its journey, and the top speed on those is about 137 mph (220 km/h); also, I'm not sure if there's an acceleration differential between how the TGV runs under 1.5kV DC wires of the traditional railroad and the 25kV 50Hz of the LGV.
 #609381  by Chafford1
 
amtrakowitz wrote:
george matthews wrote:I don't believe a diesel can do 150 mph
Why not? Enough horsepower (with power to weight ratio considerations) and the right gearing and there's no reason it can't. The Talgo XXI hit 152 mph during its tests.
150mph in tests, maybe - the official Diesel world record is 149mph by the British HST = but not in commercial service where 125mph is the maximum for diesels.

The 150mph figure doesn't make sense - if electric, why so low on a dedicated high speed line, if diesel, too high.
 #609402  by amtrakowitz
 
Depends on what you mean by "make sense" and what the real gulf between top test speed and top operating speed could be. Remember how high the TGV's test speed was (357 mph) compared to the daily operating speeds.
 #609448  by lpetrich
 
I went to this online Shinkansen schedule, and I found a travel time of 2h 33m between Tokyo and Shin-Osaka stations. I selected the Tokyo-Osaka route (the Tokaido Shinkansen) because it is the first of the shinkansens to be built ("shinkansen" literally means "new trunk line").

I estimated its length using Google Maps and planning a Tokyo - Nagoya - Hikone - Osaka car trip as an approximation of its route. The resulting distance was 558 km / 346 mi. I also consulted the Wikipedia article on the Tokaido Line, which states 515.4 km / 320 mi, yielding 202 kmh / 126 mph or 67% of top speed.

To help understand why this train seems so slow, I checked an official schedule, which lists where each train stops. The closest to a Tokyo-Osaka express goes
Tokyo - Shinagawa - Shin-yokohama - Nagoya - Kyoto - Shin-osaka

though it skips several other stops. It stops for 2 minutes in Nagoya, I estimate 1 minute for each of the other intermediate stops, and 2 minutes each to account for acceleration and braking, thus adding 11 minutes. I estimate that a Tokyo-Osaka nonstop would take 2h 22m, bumping the average speed to 218 kmh / 135 mph or 73% of top speed. This is comparable to the Paris-Lyon TGV speed.

So the projected DesertXPress average speed is close to the average speeds of the Paris-Lyon and Tokyo-Osaka trains (142 vs. 139, 135 mph). So the DesertXPress will likely require a similar maximum speed of 300 kmh / 186 mph, which is about right for off-the-shelf high-speed trains.
 #609857  by lpetrich
 
To see what the DesertXPress is competing against, I used Google Maps to plan a trip between Victorville and Las Vegas.
Distance: 198 mi / 319 km - almost all of it on I-15
Time: 2h 59m
Speed: 66 mph / 107 kmh
Some people have accused Google Maps's programmers of assuming NASCAR drivers, but the calculated speed is a plausible best-case figure.

Greyhound's buses have a scheduled time of 3h 15m, subtracting out their layover at Barstow. That gives a speed of 61 mph / 98 kmh, not much worse than the car figure. Possible "Casino Express" buses likely have similar travel times. The DesertXPress trains will thus beat the cars and the buses by at least a factor of two.

-

I suspect that the DesertXPress Victorville station will need bus service to the rest the Los Angeles area, so as to get transit-dependent and transit-preferring people, and also people who are reluctant to drive all the way to Victorville.

To obtain a bus-performance reference, I will now try to estimate the performance of those Amtrak buses that take similar routes, in particular, the San Joaquin Bakersfield buses. These buses traverse mountainous terrain that is difficult for trains to cross without expensive construction, so they may be good analogs for Victorville - LA-area buses.

Bakersfield - Las Vegas: 5h 45m / 294 mi / 51 mph
Bakersfield - Victorville: 3h 5m / 147 mi / 48 mph
Bakersfield - Pasadena: 2h 5m / 114 mi / 55 mph
Bakersfield - Los Angeles: 2h 20m / 112 mi / 48 mph

To be a bit pessimistic, I will choose 48 mph. Now for some LA-area destinations, using Google Maps routing and no intermediate stops:
San Bernardino: 35 mi / 43m
Anaheim: 75 mi / 1h 34m
Los Angeles: 81 mi / 1h 41m

Even that may be rather optimistic, since the DXP buses may have several stops along the way to their farthest stops. So riding a DXP bus from somewhere in the LA area will likely take longer than the DXP train.


I will now attempt to estimate the cost of constructing the DesertXPress line. The Paris-Strasbourg line, LGV Est, will cost about EUR 4 billion for 400 km, making EUR 10 million/km or about $20 million/mile. A distance of 190 miles yields a cost of $3.8 billion. However, land will likely be much cheaper in the southern California-Nevada desert than in eastern France, which will likely reduce the cost somewhat. And the DXP team hopes to scrimp further by using the I-15 right-of-way as much as possible.


I now turn from the line to the trains themselves. It's hard for me to find numbers on the cost of a high-speed trainset, but using a rough guess of $1 million/railcar (derived from locomotive cost) and 10 railcars/transet, I find $10 million/trainset.

As to how many trainsets the DXP will need, that depends on how many it will run. If each train has a 10-minute layover, then it can make a round trip in 3 hours, going each way in 1h 30m. So if the DXP has 1 train/hour, then it will need 3 trains to cover the schedule. With an extra one as a spare, that makes 4 trains. With the above cost figure, I find $40 million total. Unless I grossly underestimated the cost of a typical high-speed trainset, this will be much less than the cost of the line.
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