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Old December 6th, 2007, 11:49 AM   #321
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Quote:
Originally Posted by elfabyanos View Post
No no no absolutely not. The APT, when in testing, was driven around a 40 mph corner at Dover at 90 mph, with the tilting mechamism locked in the wrong directin, to test it's stability, i.e. would it tip over. The engineers were not worried about the flange losing lateral traction with the railhead, just if it would tip over. It didn't, it was fine. The technical maximum of track and train are always much higher than limits imposed. That's mainly because the passengers don't wear seatbelts.
Oh boy.
What was the designed speed limit for that certain section where they conducted the test?
As a side note tilting mechanism only off set 5%~15% of the limit and are not designed to tip over.
Seatbelts has nothing to do with the speed limits imposed on track and I really want to know why you got that notion in the first place.

Please study again how rail with fixed axle wheel negotiates curve since it is 101 train technology.
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Old December 6th, 2007, 03:14 PM   #322
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http://en.wikipedia.org/wiki/Cant_deficiency

CD = gage_se / ( 1 + R^2 * g^2 / Vact^4)1/2 - super_el.


Where:
gage_se = guage - in this case 1511.03mm
R = Radius in m
g = 9.8 m/s^2
Vact = actual velocity
super_el = super elevation in mm
cd = cant deficincy measured in mm from the virticle axis at track level.

The minimum curve on LGV Est is 4000m so let's take that as R. (7 curves are only 3200m). Let's take a hypothetical, and assume there is no banking on this track, so super_el = 0, and let's assume the train is travelling at 300 kph (88.33 m/s^2)

The equation gives as a cant deficiency of 93.4mm, which is inside the 100mm max for an LGV (as per French policy on LGVs), and well within the 150+mm max in the USA and the rest of France's network. And that's with no super elevation.

At the minimum radii of 3200m which only exist a few times on the LGV est, wihout cant super elvation the cant deficiency is 115mm, just over French policy for LGVs, but well under the technically allowed max in France, and well under again the safe maximum. It is generally considered that the cant deficiency needs to approach the rail (so that on the curve the vector of lateral accelration points towards the outside rail) before there is any danger of the train losing contact or balance endangering the vehicle. Though this varies considerably with the way the load is contained within the vehicle, the cant deficiency to achieve this is about 750mm, or 6-7 times more than the calculation shows. And even then there could be super elevation up to 100mm, enabling even higher speeds on the LGV Est. So then, why on earth do the French build their lines so unecessarily straight?

BECAUSE ITS MORE CONFORTABLE.

Forget the nonsense about maglev going round corners better. Engineers don't even take conventional trains ANYWHERE NEAR their technical limit so just drop it.

Last edited by elfabyanos; December 6th, 2007 at 03:32 PM.
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Old December 7th, 2007, 04:20 AM   #323
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Originally Posted by Tri-ring View Post
No it wasn't since I saw the footage film when the record happened. It was full of equipemnts but they were lighter than an average human.
The 500Km mark was not made on a curve either.
Let me remind you: http://www.youtube.com/watch?v=jJfDWtbioEM

Obviously the people (and equipment) onboard this train and the corners it goes around at over 500km/h are figments of my imagination.

Quote:
Fixed axis wheels do not make turns by steering because the distance between rails are fixed there by even trying to steer the axis will cause derailment.
Turns are negotiated by the differential of circumference within the inner and outer rim of the wheel, sliding the contact point between the rail and wheel from one side to the other makes it possible to turn curves.
A larger wheel can negotiate curve better because it can develop larger differentials within circumference of inner and outer rim.
I know how a train wheel works, thanks.


The maglev "following a highway" claim is a myth. As you can see here, even pushed to the extreme, TGV is perfectly safe and stable on a regular track at 350mph / 570km/h.
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Old December 7th, 2007, 06:27 AM   #324
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Quote:
Originally Posted by elfabyanos View Post
http://en.wikipedia.org/wiki/Cant_deficiency

CD = gage_se / ( 1 + R^2 * g^2 / Vact^4)1/2 - super_el.


Where:
gage_se = guage - in this case 1511.03mm
R = Radius in m
g = 9.8 m/s^2
Vact = actual velocity
super_el = super elevation in mm
cd = cant deficincy measured in mm from the virticle axis at track level.

The minimum curve on LGV Est is 4000m so let's take that as R. (7 curves are only 3200m). Let's take a hypothetical, and assume there is no banking on this track, so super_el = 0, and let's assume the train is travelling at 300 kph (88.33 m/s^2)

The equation gives as a cant deficiency of 93.4mm, which is inside the 100mm max for an LGV (as per French policy on LGVs), and well within the 150+mm max in the USA and the rest of France's network. And that's with no super elevation.

At the minimum radii of 3200m which only exist a few times on the LGV est, wihout cant super elvation the cant deficiency is 115mm, just over French policy for LGVs, but well under the technically allowed max in France, and well under again the safe maximum. It is generally considered that the cant deficiency needs to approach the rail (so that on the curve the vector of lateral accelration points towards the outside rail) before there is any danger of the train losing contact or balance endangering the vehicle. Though this varies considerably with the way the load is contained within the vehicle, the cant deficiency to achieve this is about 750mm, or 6-7 times more than the calculation shows. And even then there could be super elevation up to 100mm, enabling even higher speeds on the LGV Est. So then, why on earth do the French build their lines so unecessarily straight?

BECAUSE ITS MORE CONFORTABLE.

Forget the nonsense about maglev going round corners better. Engineers don't even take conventional trains ANYWHERE NEAR their technical limit so just drop it.
I was going through your posting concerning cant deficiency trying to understand what you wanted me to comprehend, in simple physics term cant deficiency is inertia generated through centripetal acceleration.
This means your are being pulled sideways away from the center of curve.
This can be compensated by superelevating the inner and outer rails by creating an right angle against the bank making a smoother ride.
This however does not desolve the additional load (force*weight) created by centripetal acceleration to the rails.

Here is an excerpt concerning the whole subject concerning derailment.

Quote:
The true derailment risk at high cant deficiency comes from the fact the vehicle attempts to push the track out from under itself. The safety issue is closely related to track buckling. High-speed trains may encounter speed restrictions during extremely hot weather. Greater track longitudinal forces due to temperature and greater net axle lateral forces due to cant deficiency increase the risk of track buckling.

The critical value is the net axle lateral load. In Europe, the limit is defined by the Prud’homme formula. Track lateral strength is defined by a constant term and a term linearly dependent on axle load. Relative to axle load, maximum track strength is obtained at low axle loads. Tilting vehicles intended for high cant deficiency thus have comparatively low axle loads, on the order of 15 tons to 20 tons maximum per axle. The current U.S. standard is solely proportional to axle load. However, current discussions and research findings will probably move the U.S. to adopt a limit similar in form to the Prud’homme formula.
Link for full text.

Here is a report concerning Prud’homme formula.

One side note, your figure was wrong concerning speed per second and I did not understand the equation since the unit was not formatted properly. Why is gauge represented in mm while other figures are represented in meter?
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Old December 7th, 2007, 01:36 PM   #325
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I have calculated the G force generated through centripetal acceleration for reference.
Lateral component (g)
speed 300 500
radius
2000 0.35 0.98
2500 0.28 0.78
3200 0.22 0.61
4000 0.18 0.49

Combined force(g)
speed 300 500
radius
2000 1.06 1.4
2500 1.04 1.27
3200 1.02 1.17
4000 1.02 1.11

Multiplying the weight of a cart becomes load.
Safety margin is usually 15~25% of maximum load.
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Old December 7th, 2007, 08:17 PM   #326
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Quote:
Originally Posted by Tri-ring View Post
I was going through your posting concerning cant deficiency trying to understand what you wanted me to comprehend, in simple physics term cant deficiency is inertia generated through centripetal acceleration.
This means your are being pulled sideways away from the center of curve.
This can be compensated by superelevating the inner and outer rails by creating an right angle against the bank making a smoother ride.
This however does not desolve the additional load (force*weight) created by centripetal acceleration to the rails.
Yes, you've followed up to there. What you're still not getting is that the limits imposed by the rail authorities regarding cant deficiency, or centripetal acceleration, is NOT governed by safety, but by comfort. The comfort maximum is a fraction of the safe maximum. A TGV will go down an LGV track at near enough the speed of sound before centripetal acceleration causes the train to derail. (Current suspension would probably cause the train to bounce off the track at that speed even on the straight anyway so it's irrelevent.)

Quote:
Here is an excerpt concerning the whole subject concerning derailment.



Link for full text.

Here is a report concerning Prud’homme formula.

One side note, your figure was wrong concerning speed per second and I did not understand the equation since the unit was not formatted properly. Why is gauge represented in mm while other figures are represented in meter?
Tell me about it - I got it from Wikipedia and it took me half an hour to decipher it. Formatted better it's

CD = (gage_se / ( 1 + (R^2 * g^2) / Vact^4)1/2) - super_el

But like 33Hz I know exactly how a conventional wheel / rail system works. Any current train that adheres to UK rail certification standards could quite easily throw any standing passengers over and/or splatting against the window before it would destabilize.
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Old December 8th, 2007, 12:47 AM   #327
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Quote:
Originally Posted by elfabyanos View Post
Yes, you've followed up to there. What you're still not getting is that the limits imposed by the rail authorities regarding cant deficiency, or centripetal acceleration, is NOT governed by safety, but by comfort. The comfort maximum is a fraction of the safe maximum. A TGV will go down an LGV track at near enough the speed of sound before centripetal acceleration causes the train to derail. (Current suspension would probably cause the train to bounce off the track at that speed even on the straight anyway so it's irrelevent.)

Tell me about it - I got it from Wikipedia and it took me half an hour to decipher it. Formatted better it's

CD = (gage_se / ( 1 + (R^2 * g^2) / Vact^4)1/2) - super_el

But like 33Hz I know exactly how a conventional wheel / rail system works. Any current train that adheres to UK rail certification standards could quite easily throw any standing passengers over and/or splatting against the window before it would destabilize.
I see want you're saying but your are missing two factors as written within the link I provided.
One, cant deficiency addresses the possibility of derailment concerning the differencial of attack angle in the front axle and rear axle of the cart.

Second and major factor is that force generated through centripetal acceleration is the major factor to derailment and as you can see within the cant deficiency equation it does not address mass or weight of the train so it's irrelevent to what I am talking about.

One question concerning the equation, where did the trigonometric value disappear ?
Since centripetal acceleration is a lateral component independent from the vertical component(g), I don't understand why g is included within the equation without a trigonmatric value.
Am I missing something?
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Old December 8th, 2007, 02:29 AM   #328
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reroute track in-land in CT to hartford --> PVD-->Boston. More rural there. Highspeed all the way!! Track could parallel interstate between danbury and Hartford, comming into NYC via the westchester line (metro north). No other way to upgrade CT track due to coastal towns and nimbies.
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Old December 8th, 2007, 02:33 AM   #329
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Indeed the first TGV line had made an ROI of 15% after its first decade.

In terms of ridership, a TGV line can handle a train every 3 minutes (and some are at capacity). With typical a maximum of 1200 passengers per train, then over a 16 hour day, the line would carry 768000 passengers if used fully.

There is a load of useful stuff on this here: http://answers.google.com/answers/threadview?id=595477
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Old December 8th, 2007, 02:34 AM   #330
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reroute track in-land in CT to hartford --> PVD-->Boston. More rural there. Highspeed all the way!! Track could parallel interstate between danbury and Hartford, comming into NYC via the westchester line (metro north). No other way to upgrade CT track due to coastal towns and nimbies.
Tunnels?
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Old December 8th, 2007, 02:46 AM   #331
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too expensive.

Two proposals

1) Track follows I-684 to danbury, waterbury, hartfrd, providence, boston.

2) Follow Merrit PKWAY to New Haven..then Hartford, PVD, Boston.

Lots of open forest land along the route, low density. Cheaper to build a true HSR - shorter time even though longer route.
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Old December 8th, 2007, 06:09 AM   #332
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Which illustrates why "true HSR" would have hemorrhaged cash in Florida -- the HSR "Vision Plan" called for one train each way PER HOUR. Spending billions of dollars to build a HSR line from scratch, just so you can run one train per hour, is absolute madness. There is no sane justification for building a brand new HSR line just to run one train per hour on it. It also illustrates why 110mph ISR "baby steps" make more sense in most parts of America right now. Most people agree that the demand is there for one train per hour. Maybe even two, during peak travel periods. But even in the NEC, you'd be hard-pressed to fill a full-length HSR train leaving Grand Central Station every 3-6 minutes, even at 5pm. I don't even think New York and DC's subways run every 3 minutes... so the theoretical carrying capacity of a HSR line is largely moot.

With service that infrequent, you could LITERALLY run 180mph trains on a single track, with double-tracked stations, and passing trains would barely even notice each other's presence if the schedulers and dispatchers were "on the ball" and timed them to both arrive at some station along the way within a minute or two of each other. It's also a major reason why grade crossings aren't a huge problem for 110mph trains... if you only have one per hour, the gates are only going down twice per hour at any given road crossing, and the whole thing (from first flashing light to rising gate after the train blows past in 5 or 6 seconds) will probably take less time than most of the red lights in Orlando.
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Old December 8th, 2007, 06:19 AM   #333
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Whats the current progress on the 110mph train in Florida -- it seems all talk no action. I don't see why a tilting train couldn't work in Florida - would brand new tracks be needed for a tiltin train at 125mph? Or just upgrades to existing tracks? The Jet train would be a good step foward
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Old December 8th, 2007, 01:34 PM   #334
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Quote:
Originally Posted by miamicanes View Post
Which illustrates why "true HSR" would have hemorrhaged cash in Florida -- the HSR "Vision Plan" called for one train each way PER HOUR. Spending billions of dollars to build a HSR line from scratch, just so you can run one train per hour, is absolute madness. There is no sane justification for building a brand new HSR line just to run one train per hour on it. It also illustrates why 110mph ISR "baby steps" make more sense in most parts of America right now. Most people agree that the demand is there for one train per hour. Maybe even two, during peak travel periods. But even in the NEC, you'd be hard-pressed to fill a full-length HSR train leaving Grand Central Station every 3-6 minutes, even at 5pm. I don't even think New York and DC's subways run every 3 minutes... so the theoretical carrying capacity of a HSR line is largely moot.
Firstly, this is an extreme illustration of what a line can carry - not what it needs to break even. Secondly, the service pattern doesn't need to be A to B - the HSR lines in Europe are the backbone used by services starting from and going to a multitude of destinations at each end.



Quote:
With service that infrequent, you could LITERALLY run 180mph trains on a single track, with double-tracked stations, and passing trains would barely even notice each other's presence if the schedulers and dispatchers were "on the ball" and timed them to both arrive at some station along the way within a minute or two of each other.
This is exactly what is being proposed for lines in several developing world countries

Quote:
It's also a major reason why grade crossings aren't a huge problem for 110mph trains... if you only have one per hour, the gates are only going down twice per hour at any given road crossing, and the whole thing (from first flashing light to rising gate after the train blows past in 5 or 6 seconds) will probably take less time than most of the red lights in Orlando.
That's may be, but it doesn't seem to stop people running the lights in many other states where the frequencies are just as low.
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Old December 8th, 2007, 03:50 PM   #335
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Quote:
Originally Posted by Tri-ring View Post
One, cant deficiency addresses the possibility of derailment concerning the differencial of attack angle in the front axle and rear axle of the cart.
Cant deficiency doesn't address this. Cant deficiency applies to any cornering movement, including cars, planes and maglev - none of which can possibly derail. It is normally measured in degrees, though for a fixed curve and fixed gauge railway track it can happily be given as a distance from the centre of the track.

Quote:
Second and major factor is that force generated through centripetal acceleration is the major factor to derailment and as you can see within the cant deficiency equation it does not address mass or weight of the train so it's irrelevent to what I am talking about.
As above, cant deficiency isn't about this. Mass won't affect the value of cant deificiency - the centripetal acceleration is dictated by the velocity and the track curvature. The Prud'homme formula is about track movement, progressively over long periods of time, causing safety problem. If the track was built on a 5 metre deep block of steel that absolutely wouldnt move under any circumstances, this analysis would not help us to understand the speed at which the train could be predicted to derail from a curve on it.

Quote:
One question concerning the equation, where did the trigonometric value disappear ?
Since centripetal acceleration is a lateral component independent from the vertical component(g), I don't understand why g is included within the equation without a trigonmatric value.
Am I missing something?
I don't see why a trigonometric function would be required - centripetal acceleration is uniform around a constant radius curve.
Gravity is a compenent of the resulting vector. A proportion of the acceleration due to gravity will be deflected by the track inwards, varying with the angle of the the track's banking. Since this again is a constant independent of speed or position on the curve or radius of the curve I see no reason for a kind of trigonometric function.

In order to model how a train may derail due to high cant defiency we would need to know the mass of the train, the center of gravity, virticle and lateral wheel/rail reaction vectors and a pretty good knowledge of the suspension system which would introduce a few things aswell. We would find out that in most circumstances the train would effectively topple over, leaning over to the point where the wheel is at quite an angle to the track, and can slide over it. Cant deficincy would increase as this point is reached, but the the height and mass of the vehicle are the determining factors - a 100 ton 1 meter high vehicle would have far less trouble than a 5 ton 20 meter high one - yet they wold both experience the same cant deificency at the same speed.

Trains in service in the uk that use tilt technology have a cant defiency of over 10 degrees over many curves. Thats because the cant defiency experieced by the passengers is reduced to under 4 degrees by the vehicle body tilting 5 degrees. But this doesn't alter the physics between the track and train.
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Old December 8th, 2007, 05:27 PM   #336
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Quote:
Originally Posted by elfabyanos View Post
Cant deficiency doesn't address this. Cant deficiency applies to any cornering movement, including cars, planes and maglev - none of which can possibly derail. It is normally measured in degrees, though for a fixed curve and fixed gauge railway track it can happily be given as a distance from the centre of the track.
You should read links which are provided.

Quote:
Wheelset angles of attack decrease with increased cant deficiency. The diagram at the top right of Figure 7 shows the usual curving orientation of a truck at balance speed. The leading axle takes an angle of attack and the trailing axle takes a near-radial position. The bottom right diagram shows the curving orientation at high cant deficiency. In this condition, the leading axle moves into a radial position (the angle of attack decreases) while the trailing axle goes to an over radial position. This has important consequences in terms of derailment safety.
This is the point I was talking about in the first place.

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Originally Posted by elfabyanos View Post
I don't see why a trigonometric function would be required - centripetal acceleration is uniform around a constant radius curve.
Gravity is a compenent of the resulting vector. A proportion of the acceleration due to gravity will be deflected by the track inwards, varying with the angle of the the track's banking. Since this again is a constant independent of speed or position on the curve or radius of the curve I see no reason for a kind of trigonometric function.
Gravity is a vertical component, which has no influence to lateral centripetal acceleration. Gravity is not a resulting vector, inertia is. Inertia is represented as m/t^2 (acceleration). I did not understand why gravity is included within this equation to obtain a figure that is suppose to be independent from effect of gravity in the first place.
Trigonometric function is needed to combine lateral component, centripetal acceleration with vertical component, gravity to gain combined force in order to compensate superelevation.


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Originally Posted by elfabyanos View Post
In order to model how a train may derail due to high cant defiency we would need to know the mass of the train, the center of gravity, virticle and lateral wheel/rail reaction vectors and a pretty good knowledge of the suspension system which would introduce a few things aswell. We would find out that in most circumstances the train would effectively topple over, leaning over to the point where the wheel is at quite an angle to the track, and can slide over it. Cant deficincy would increase as this point is reached, but the the height and mass of the vehicle are the determining factors - a 100 ton 1 meter high vehicle would have far less trouble than a 5 ton 20 meter high one - yet they wold both experience the same cant deificency at the same speed.
Actually your missing an important factor which is lateral load limit of the rail. Other factor would be heat deformation rate of rail.
Again read the link I have provided.
Simply put heavy load(regardless of height and/or center of gravity) at high speed at steep curves destroys rails resulting to derailment.
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Old December 8th, 2007, 07:03 PM   #337
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Whats the current progress on the 110mph train in Florida -- it seems all talk no action.
At the moment, FDOT's preoccupied with getting CSX's freight operations relocated from the JAX-Orlando segment to the JAX-Auburndale segment (that runs through Ocala) to clear the way for FDOT's purchase of the CSX tracks for Orlando's commuter rail, which will also be used by future intercity trains. They have to get that done first, because the tracks through Orlando will be expensive to buy (comparatively speaking... it's still a drop in the bucket compared to the cost of trying to ram a brand new rail corridor through the area), and by officially justifying it as a "commuter rail" project, they can get the federal government to pay a big chunk of its purchase and improvement costs.

Basically, FDOT's strategy is to make sure that their plan is so financially bulletproof, not even Wendell Cox will be able to find an opportunity for it to lose money. The upside is that it means that their eventual success is nearly assured (the legislature won't vote against it if it won't lose money). The downside is that it's going to take about a decade to make it happen, because they have to take advantage of every possible opportunity to get the federal government to buy corridors for them since that's going to be their largest single cost. They already own WPB to Miami. They'll own Kissimmee to DeLand fairly soon. From that point, DeLand to Jacksonville will be cheap (since it'll be almost completely devoid of commercial value). So will Auburndale to West Palm Beach (it costs CSX more money to maintain it than they actually make from all their operations on it). That leaves Tampa to Kissimmee as the only expensive segment left. If push came to shove, they could launch phase 1 with only Miami to Orlando service (Miami-Orlando would probably take in enough passenger revenue to pay its own costs, even without Miami-Tampa and Tampa-Orlando), and use its objective success to sell the Tampa segment to the legislature a year or two later (since its total cost would be a fraction of the original Miami-Orlando segment's costs, and would more or less double the service's ridership by adding Miami-Tampa and Tampa-Orlando).

In other words, you aren't going to see FDOT boldly calling for the state to indiscriminately throw money at them and "build the future." They're going to show up at the capitol building quietly, business plan in hand, accountants in tow, and sell them on an incremental plan with minimal financial risk to the state that's likely to be popular with voters and tourists alike. And re-emphasize a few hundred times that it'll be cheap, and won't require perpetual subsidies. It won't make the HSR firebrands happy, but it will get us frequent, fast, and reliable rail service in a few years -- probably long before ANYONE in America successfully launches "true" HSR for revenue service.

Quote:
That's may be, but it doesn't seem to stop people running the lights in many other states where the frequencies are just as low.
Which is why FDOT built concrete barricades in the median at crossings in Fort Lauderdale... so people can't try to drive around the lowered gates. They also modified the traffic lights where there's a light "just beyond" a crossing, so that there are now two lights... the one "before" the tracks turns red a few seconds before the one "after" the tracks, to minimize the likelihood of a daydreaming driver getting stuck on the tracks by gridlocked traffic. And when a train IS approaching, the traffic lights "before" the tracks turn red when the gates go down, but the lights "after" them stay green for an extended period of time to clear the area between the tracks and second light. Remember... Americans who'll ignore a train signal are still conditioned from birth to regard a red traffic light as sacred. Even at 4am, in the middle of the Everglades, with no other cars in sight, Americans will still sit at a red traffic light for 2 minutes waiting for it to turn green.

Last edited by miamicanes; December 8th, 2007 at 07:16 PM.
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Old December 8th, 2007, 07:33 PM   #338
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Quote:
Originally Posted by Tri-ring View Post
You should read links which are provided.
This is the point I was talking about in the first place.
The discussion is centering around the possibility of maglev going round a tighter corner than conventional rail. The links you are providing discuss how a train might derail, and what the loads are. But this is much like discussing how a jumbo jet's wings might fare if the pilot started doing dive-bomb manouvres - it wouldn't have much relevence to normal in-service performance statistics, because a pilot wouldn't be allowed to push the plane that far as it wouldn't make for a very confortable ride.

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Gravity is a vertical component, which has no influence to lateral centripetal acceleration. Gravity is not a resulting vector, inertia is. Inertia is represented as m/t^2 (acceleration). I did not understand why gravity is included within this equation to obtain a figure that is suppose to be independent from effect of gravity in the first place.
Trigonometric function is needed to combine lateral component, centripetal acceleration with vertical component, gravity to gain combined force in order to compensate superelevation.
No gravity doesn't have any effect on the centripetal acceleration. That's not what I said. Unless gravity is acting on a body that is resting on a completely flat surface, it is responsible for a lateral force on the body due to the slope deflecting the effect of gravity. If a ball rolls down a hill is gravity not responsible for the sideways element of the balls motion, aswell as it's virticle descent?

I don't quite understand the issue with the equation - if you would notate how you think it should appear instead it may help.

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Actually your missing an important factor which is lateral load limit of the rail. Other factor would be heat deformation rate of rail.
Again read the link I have provided.
Simply put heavy load(regardless of height and/or center of gravity) at high speed at steep curves destroys rails resulting to derailment.
I did read the link but I found it irrelevent to discussion. Technical failure happens at speeds way above the maximum speeds permitted by what is effectively a 'comfort' policy the rail regulators. As people are the same people whether they be in a maglev or a conventional train I see no reason why it would be permissable to fling people round corners more in one mode of transport than another. I must stress again that trains can go round corners a lot faster than they are allowed, and this restriction is not a safety-critical one. It obviously would have implications for maintenance which must be the consideration for the lower tolerances on the LGVs, in addition to the comfort.
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Old December 8th, 2007, 08:10 PM   #339
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ridiculous - disgusting that it takes 10 years to implement slow rail in the biggest economy in the world -- What a long, drawn out process you described. Its ludicrous. Sounds like something a third world nation would be doing.
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Old December 9th, 2007, 10:13 AM   #340
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Just think of it as old-money frugality, vs nouveau-riche extravagance. Third-world countries feel like they have to prove to others that they're worthy of respect. America yawns, then acts amused when everyone else pretends to be sleepy and ready to go to bed just so they can be like us, too.
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