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[responding to a post near top of thread to prevent the use of "forum sliding" tactics--refer to article in my signature if you are unaware of the tactic]

While the mainstream US media largely ignores NSA/US spying, other news has to take the place of those stories--something bigger and "better", so to speak.

Let's start with the train wreck in Lac Megantic--not a single story in mainstream media regarding SCADA systems used on most trains these days. Why not?

http://www.getransportation.com/rail/rail-products/locomotives/on-board-systems/train-controlscada.html [getransportation.com]

The owner of the rail company involved spews disinformation to distract from a valid concern--that trains can be remotely operated (including brakes!) by a system easily hacked. Who might have such a motivation?

Let's move on to the Asiana crash at SFO.

The following from the Economist has some interesting information about the controls of airliners. The most relevant information is discussed in the last section of the article.

http://www.economist.com/node/787987 [economist.com]

I shouldn't have to remind everyone that Boeing is inextricably involved with government operations--they build the best military aircraft out there, including drones. In both incidents, the operators of these vehicles were blamed before any reasonable amount of investigation could possibly have been completed. Why is that?

zimmerman innocent!! zimmerman guilty!! "Oh my God. Just when I thought this case couldn't get any more bizarre," Saudi Princess out on bail Holmes acquitted Holmes Confesses Stock Market recovers Stock market plunges Sarah Palin Pregnant Student Loans 45% Interest Offer Students Access to Morning-After Pill FREE XBOX SONY ELECTRONIC ARTS VALVE STEAM FREE DOWNLOAD reddit closing facebook shares /. china pork senate finance committee dollar plunges twinkle Twinkie Egypt Christians targeted cook a steak killed kittens gold cellphone UC Berkeley stolen marijuana Texas secedes! LDS LSD SD SC Abortion Fracking Skateboard lost Toronto Red Cross charges of adultery phone number

[responding to a post near top of thread to prevent the use of "forum sliding" tactics--refer to article in my signature if you are unaware of the tactic]

While the mainstream US media largely ignores NSA/US spying, other news has to take the place of those stories--something bigger and "better", so to speak.

Let's start with the train wreck in Lac Megantic--not a single story in mainstream media regarding SCADA systems used on most trains these days. Why not?

http://www.getransportation.com/rail/rail-products/locomotives/on-board-systems/train-controlscada.html

The owner of the rail company involved spews disinformation to distract from a valid concern--that trains can be remotely operated (including brakes!) by a system easily hacked. Who might have such a motivation?

Let's move on to the Asiana crash at SFO.

The following from the Economist has some interesting information about the controls of airliners. The most relevant information is discussed in the last section of the article.

http://www.economist.com/node/787987

I shouldn't have to remind everyone that Boeing is inextricably involved with government operations--they build the best military aircraft out there, including drones. In both incidents, the operators of these vehicles were blamed before any reasonable amount of investigation could possibly have been completed. Why is that?

And, just to keep the sheep happy, why the hell is Zimmerman being tried by a jury of only six of his "peers"? Every state-level criminal court I've heard of had thirteen, plus alternates.

... about where hybrids with power storage have gone, if anywhere?

General Electric is coming out with a diesel-electric with battery storage to recover some of the energy used in braking. Dynamic braking on diesel-electrics normally dumps the energy into (huge) resistors, and that can be put into batteries, if you want to carry all those batteries around. Whether this is a win depends on the way the loco is used. It's probably a win for switch engines,which stop and start frequently, and a lose for road locos on long runs, which don't.

Almost all high speed trains are pure electrics, drawing their power from centenaries. Newer ones put braking power back into the power line if possible. This involves a frequency conversion and some very large semiconductors.

The US has a freight rail system that is the envy of Europe. (Europe is ahead in passenger rail, but that loses money.) Intermodal traffic (containers) is way up over the last decade, and profitable. There's new rail construction going on, and rails and locomotives have been upgraded in recent years.

Modern large locomotives use what are essentially giant computer-controlled servomotors to drive the wheels, so that all the wheels on all the locomotives stay in sync and share the load equally, which means they can all be torqued up to just below where they start to slip. This means fewer locomotives per train, little or no wheel slip, and the ability to coordinate many locomotives spread throughout a train.

Last year, Union Pacific ran a train 3.5 miles long from Los Angeles to Denver. Average freight train length in the US is now 6500 feet and climbing. That replaces a lot of trucks. Since Los Angeles built a no-grade-crossing rail connection to the port there, far fewer trucks are moving to the port.

Europe still has a lot of little 2-axle freight cars. Those disappeared from US trackage some time before World War Two, replaced by the standard big four-axle cars still used today. The bigger cars are also stronger, with a consistent minimum coupler strength, which means longer trains are possible.

Mixing high speed passenger trains and freight on the same track cuts severely into freight capacity. Each passenger train uses up the track time of six freights.

The OP isn't entirely incorrect. GE for one is designing locomotives with more sophisticated power systems to increase fuel efficiency. Namely, they are incorporating regenerative braking and a battery system;

http://www.getransportation.com/rail/rail-products/locomotives/hybrid-locomotive.html

One of the real reasons behind this is that the gear train to connect a gas turbine to a propeller is a huge pain. Turbine shaft speeds are around 20,000 RPM, and this has to be stepped down to 200 RPM or so for the propeller. There's a clutch and reversing gear, too. Often the gearbox is bigger than the engine.

Reverse with a turbine is a headache. Some marine diesels are built so they can run in either direction, but that's not an option with a turbine. So there's either a really big gearshift, or a second powerplant for reverse operation.

Thus, there's ongoing interest in going to electric transmission, like a locomotive. It's not a new idea; an electric transmission was tried on a ship before WWII. But it works much better with modern power semiconductors. Locomotives do this now. Modern locomotives use AC to DC to variable frequency polyphase AC conversion to drive the motors. This takes large switching power supplies, using very large semiconductors. It's a solved problem; GE locomotives have been doing this for ten years now, and their competitors now have comparable technology. Moving the technology to ships is an obvious move at this point.

There's also a Navy effort to develop a permanent magnet motor (!) big enough for shipboard propulsion. This gets rid of the field coils and increases efficiency. I'm not sure how that's coming along.

This is routine progress being made in heavy machinery. The combination of electronics and really big gears and motors can do things neither can do alone.

http://www.getransportation.com/na/en/hybrid.html

The energy dissipated in braking a 207-ton locomotive over the course of a year is enough to power 160 households for that year. The hybrid locomotive will capture that energy and use it to produce more horsepower and reduce emissions and fuel use.

It's actually pretty cool. The "battery" is made up of several thousand pound molten salt cells, which can deliver over 2,000 horsepower in under a second.

The advantages seem obvious to me

• Diesel engine runs at an efficient speed when needed
• You lose the transmission/drivetrain complexity
• You get gobs of low end torque
• 4 motors = AWD = you could do funky traction control stuff with four independant motors
• You get regenerative braking built in.
• We've got 50+ years of experience building them for very high demand applications. We know they can handle abuse.

But they're not pure hybrids. The energy from the regenerative braking systems on diesel-electric locomotives is simply run through a big-ass electric heater grid and radiated away, not recaptured and stored in batteries.

But GE is working on a "pure" hybrid: https://www.getransportation.com/general/locomotiv es/hybrid/hybrid_default.asp locomotive...

Cars and big trucks are impressive, until you see a 200-car consist being hauled across wyoming at 75mph, keeping up with traffic on I-80.

How about a deisel-electric engine that delivers 4500 horsepower? I'm sure it doesn't get anywhere near close to 50 mpg, though...

I don't think Union Pacific builds their own equipment anymore. But maybe General Electric or Electro-Motive / GM EMD could provide build the ship.

Hmm, I can't seem to find the "Add To Shopping Cart" button on either of those websites. Internet shopping revolution my foot!

• Batteries have relatively low energy density (compared to gasoline). Gasoline stores about 36 kWh energy / gallon, or about 12 kWh/kg mass. Your best lithium ion batteries are currently around 150 Wh/kg.
• Batteries tend to have a relatively lower power density. They're happiest if they're discharged over the course of an hour or more. Push the current higher than that, and they tend to heat up, turning some of their stored energy into heat, which means less electrical energy actually comes out of the battery. Lookup Peukert numbers if you want more info on that.
• The amount of battery mass you have to add to get a decent range makes for a very heavy vehicle.

So there.

The lower temperature and reduced solar wind definately help the sounds carry further. It's also worth noting that train engines and their massive weight on tracks produce intense low frequency sounds that are nondirectional by nature.

Train engines are 16 to 18 cylinders, 10-15 liters per cylinder and usually run at around 1000 RPM.

Some locomotive engine specifications:
* GE Transportation Systems
* GM's Electro-Motive Division