Higher speed rail- 125mph will put GE at disadvantage

to get the answer to Andrew's question , we go back to 1976 , to a benchmark that held for maybe 20 - 25 years , the Brtish hst125 .
http://en.wikipedia.org/wiki/InterCity_125
While they calculated 4500 hp been enough , that was with liteweight british stock , and not the aircon and hep loads of today .
I think in the american context you would want 3000-4000 hp on each end to cater for a 6 -8 car train .
you can change the gearing , but you sacrifice acceleration .
The hst 125 sets were doing 100mph before they cleared the inner london station ring .

mtuandrew wrote:

David Benton wrote:125 mph with a diesel , only way to do that with a reasonable weight is to put a loco on each end .

Why not two locomotives at the front? For that matter, why two locomotives? A single 4200 hp locomotive should be able to reasonably haul at least four cars at 125 mph.

goodnightjohnwayne is correct - 125 mph with a diesel is no great feat, only a matter of changing the gear sets. In fact, railroads do it all the time, trading top speed for tractive effort. Assuming that there are no tracking problems with the trucks or other safety issues - of course Amtrak would go to Pueblo to recertify the class at higher speeds - I don't see why an existing P42 couldn't serve at higher speeds.

The ALP-45dp can do 125. Take out the panto power and there you go. Oh wait, that isn't GE's design. Sucks to be them.

Oh wait ,it only does 100 mph in diesel mode

Single Genesis locomotives already hit 110 mph on Empire Service trains, right?.

The EGE wrote:Locos at both ends eliminates the need to turn trains or use cab cars. I'd sure as hell rather have a locomotive than a cab car going through grade crossings - safer for passengers and crew alike.

I suppose EMUs and DMUs are out for going across railroad crossings too, even though they do that all the time?

Sure, they certainly do. But any line that adds electrification anymore is likely to be grade-separated as well (as electrification makes the most sense at higher speeds), and there's no commercial DMU in the US.

David Benton wrote:to get the answer to Andrew's question , we go back to 1976 , to a benchmark that held for maybe 20 - 25 years , the Brtish hst125 .
http://en.wikipedia.org/wiki/InterCity_125
While they calculated 4500 hp been enough , that was with liteweight british stock , and not the aircon and hep loads of today .
I think in the american context you would want 3000-4000 hp on each end to cater for a 6 -8 car train .
you can change the gearing , but you sacrifice acceleration .
The hst 125 sets were doing 100mph before they cleared the inner london station ring .

Lovely trains. I highly enjoyed my rides on them from Paddington to Penzance and points between, and I truly wish there was anything comparable on this side of the Atlantic.

You're probably right regarding the power requirements. A typical Amfleet is about half again as heavy (57 tons) as a Mark III coach (36 tons), and the typical HST125 sets have 7 or 8 cars. Amtrak could probably make do with one Genesis for a four car Amfleet train at 125 mph, but they'd probably opt for two for reliability's sake anyway. For that matter, I recall that posters said the Michigan trains were using a Genesis at each end once they got bumped to 110 mph - perhaps Tadman could confirm this?

Anyway. The speed itself doesn't seem to be the issue, rather that the original poster asserts that GE doesn't have a design safely certified for that speed. I assume that should 125 mph diesel service be seriously proposed, GE will rectify that issue.

mtuandrew wrote:For that matter, I recall that posters said the Michigan trains were using a Genesis at each end once they got bumped to 110 mph - perhaps Tadman could confirm this?

To operate a locomotive on the rear I think they would also need cables extending from the front unit to the rear unit. The passenger cars would need a receptacle. I'm not saying the Amtrak cars don't have it, I'm just wondering if they do?

Tommy Meehan wrote: To operate a locomotive on the rear I think they would also need cables extending from the front unit to the rear unit. The passenger cars would need a receptacle. I'm not saying the Amtrak cars don't have it, I'm just wondering if they do?

Some Amtrak passenger cars are equipped with the necessary cabling and sockets. I believe all the Amtrak California cars and some other stock.

JayBee wrote:

Tommy Meehan wrote: To operate a locomotive on the rear I think they would also need cables extending from the front unit to the rear unit. The passenger cars would need a receptacle. I'm not saying the Amtrak cars don't have it, I'm just wondering if they do?

Some Amtrak passenger cars are equipped with the necessary cabling and sockets. I believe all the Amtrak California cars and some other stock.

Just about every Amfleet I and Horizon car have the necessary cabling and sockets, I'm not sure about Amfleet IIs. Every California Amtrak & Surfliner "Superliners" have them too, but only a few standard Superliners do (used on Heartland Flyer and occasionally on Michigan trains). I'm not sure if Amtrak plans to do so on all Superliners as they are being refurbished. My point is that all Amtrak cars can be.

electricron wrote:Just about every Amfleet I and Horizon car have the necessary cabling and sockets, I'm not sure about Amfleet IIs. Every California Amtrak & Surfliner "Superliners" have them too, but only a few standard Superliners do (used on Heartland Flyer and occasionally on Michigan trains).

Thanks, I wasn't aware of that. Yet on the Empire Corridor trains hit three digits with a single GE unit.

Heck I know an Empire Service locomotive engineer that used to get the old Amtrak FL-9s up to ninety or pretty close to it. He said it took a while and the ride wasn't too great, but they could do it.

Tommy Meehan wrote:

electricron wrote:Just about every Amfleet I and Horizon car have the necessary cabling and sockets, I'm not sure about Amfleet IIs. Every California Amtrak & Surfliner "Superliners" have them too, but only a few standard Superliners do (used on Heartland Flyer and occasionally on Michigan trains).

Thanks, I wasn't aware of that. Yet on the Empire Corridor trains hit three digits with a single GE unit.

Heck I know an Empire Service locomotive engineer that used to get the old Amtrak FL-9s up to ninety or pretty close to it. He said it took a while and the ride wasn't too great, but they could do it.

A single unit with less horsepower to boot! I'd guess that the almost 0% grade is what makes that possible, since the consists still need HEP.

Does any poster know whether the safety requirements for 125 mph locomotive operation are different than those for standard-speed operation? It seems clear to me that there isn't a technological barrier keeping GE, EMD/Progress, MPI, Bombardier, or any of the small builders from producing a 125 mph-capable diesel. After all, EMD and Alco were able to nearly reach that speed in the 1940s and 1950s, and the Turbotrain, Turboliner, and LRC topped it in the 1960s and 1970s. So, it seems that there must be a regulatory barrier instead.

The EGE wrote:Sure, they certainly do. But any line that adds electrification anymore is likely to be grade-separated as well (as electrification makes the most sense at higher speeds), and there's no commercial DMU in the US.

Why would it be "likely"?

Since we're talking 125 mph, neither electrification nor grade separation would be necessarily considered.

In the United States this day and age, any project that involves electrifying a intercity line is probably going to involve raising speeds at least to 150mph - the cost/benefit is probably not there for speeds achievable by diesels. At 150mph, you simply can't have grade crossings - they end up getting closed for too long, and the energies involved in a collision with even a small car may be enough to derail a train.

At 125mph, we're still in the range of (possible double-headed) diesels. I don't know about grade crossings at that speed.

amtrakowitz wrote:

The EGE wrote:Sure, they certainly do. But any line that adds electrification anymore is likely to be grade-separated as well (as electrification makes the most sense at higher speeds), and there's no commercial DMU in the US.

Why would it be "likely"?

Since we're talking 125 mph, neither electrification nor grade separation would be necessarily considered.

Grade separation at crossings would be necessary for all practical purposes because not one foolproof pre-approved at grade crossing safety device exists. The costs to make one and get it approved will probably be higher than building a grade separated crossing.

Much of the St. Louis to Chicago (Alton to Dwight) track refurbishment is already updated on Google Earth. You can take a bird's eye view of the entire route if you so desired. While it might be practical to grade separate most of the crossings within city and town limits, it certainly wouldn't be at most of the rural crossings. And the cheapest way to grade separate most of the city and town crossings will be to elevate the tracks over the streets, that action would certainly cause a rise in opposition from the locals. It'll be easier politically to grade separate the rural crossings.

Let's face reality, as long as the rail corridors are owned by the railroad companies making all their profits with freight operations, you're not going to get faster than 110 mph passenger trains on shared tracks. And I would suggest that the freight railroad companies would prefer a maximum of 90 mph. You're only going to see greater than 90 mph trains on tracks owned by government agencies, with the St.Louis to Chicago corridor being the sole exception. Therefore, buying new diesel locomotives capable of speeds over 110 mph is unnecessary.