OvermodNo -- this is a meaning that would be much more familiar to Tree than to US&S, I'm afraid...
Larry Resident Microferroequinologist (at least at my house) Everyone goes home; Safety begins with you My Opinion. Standard Disclaimers Apply. No Expiration Date Come ride the rails with me! There's one thing about humility - the moment you think you've got it, you've lost it...
Overmod I might add that, according to PWW, "most" of the vertical support turns out to be via extended contact patches on the treads, not in 'flange bearing' as it's normally construed. Since your actual second-sentence point was 'bearing the load as track rails do' (and not 'flangelike' guidance as you said it was) there is a certain amount of real semantic leeway here -- but I'd still be very careful conflating what intact tracks do in steering and guiding with the situation off the tracks entirely.
I might add that, according to PWW, "most" of the vertical support turns out to be via extended contact patches on the treads, not in 'flange bearing' as it's normally construed. Since your actual second-sentence point was 'bearing the load as track rails do' (and not 'flangelike' guidance as you said it was) there is a certain amount of real semantic leeway here -- but I'd still be very careful conflating what intact tracks do in steering and guiding with the situation off the tracks entirely.
Overmod Murphy Siding When I look at Google Maps, the end of our spur at work is 259 yards from my desk. If you knew how to get that number, why not do it for the area 'concerned'? Just measure off about 250 yards from where the Mercy was docked, and then measure to end-of-track...
Murphy Siding When I look at Google Maps, the end of our spur at work is 259 yards from my desk.
If you knew how to get that number, why not do it for the area 'concerned'? Just measure off about 250 yards from where the Mercy was docked, and then measure to end-of-track...
Thanks to Chris / CopCarSS for my avatar.
SD70DudeI'll have to make sure to get one that is insulated.
And very heavy in the seat -- the apparatus will likely to be kept honed by lower-level management, and probably strongly spring-loaded. (I would not put it past Progress Rail to use small gas charges, in which case you might need to repurpose suits for IED rather than AED 'defense', or perhaps have someone Scotchguard a flak suit...)
With machine-vision nerds in the picture, I'd be strongly worried about implicit code that senses proper posterior engagement in deployment. So be sure there is a layer outside the PPE (personal posterior ensurement) that has the correct conductivity to fool the embedded logic...
Overmod SD70Dude I wonder if that qualification will mean we will be expected to repair those seats ourselves when they inevitably break down..... How will you know? It's the periodic 92-day testing that is going to be the real pain in the... perhaps I need a better metaphor, as this is a little too close to ... maybe I need a better metaphor that doesn't involve painful proximity at all. An ominous point to ponder, perhaps: isn't the alerter system part of the critical safety equipment that has to be tested every time a crew takes a train? Better start googling manufacturers of dielectric underwear with a flesh-like surface layer...
SD70Dude I wonder if that qualification will mean we will be expected to repair those seats ourselves when they inevitably break down.....
How will you know?
It's the periodic 92-day testing that is going to be the real pain in the... perhaps I need a better metaphor, as this is a little too close to ... maybe I need a better metaphor that doesn't involve painful proximity at all.
An ominous point to ponder, perhaps: isn't the alerter system part of the critical safety equipment that has to be tested every time a crew takes a train? Better start googling manufacturers of dielectric underwear with a flesh-like surface layer...
I've been thinking of picking up a biohazard suit anyway, what with the current pandemic and all. I'll have to make sure to get one that is insulated.
Greetings from Alberta
-an Articulate Malcontent
Overmod Euclid The pavement also retained enough solid structure to suppor the load as track rails do. If I were you, I wouldn't use "track rails" in two very different senses in two succeeding sentences. You lost important information when you did that.
Euclid The pavement also retained enough solid structure to suppor the load as track rails do.
If I were you, I wouldn't use "track rails" in two very different senses in two succeeding sentences. You lost important information when you did that.
I used the term track rails in two very different senses because that is exactly what I intended to do. That is why I put quotation marks around the word rails in one sentence, and not in the other sentence. In the first sentence, I was referring to flanges pressing dents into the pavement that then provided the guidance normally provided by track rails.
In the second sentence, I was using the term track rails as it normally refers to the rails of a railroad track. In any case, my point had nothing to do with the ability of track rails to carry a load except for the ability to prevent the wheels from breaking up the pavement and defeating the guidence I was refering to.
I used the term guidance because I was referring to the guidance provided by the rails of a railroad track guiding the wheel flanges. My point was that with the flanges pressing linear dents into the asphalt, the wheel flanges were guided by those grooves.
You are reading a lot more information into what you assume I meant to say than what I actually meant to say. No information was lost in what I said and meant to say.
SD70DudeI wonder if that qualification will mean we will be expected to repair those seats ourselves when they inevitably break down.....
Overmod NDG Overmod "Microsleep detec-ted. Charging.... CLEAR!" You mean it reads Signals, Too?? No -- this is a meaning that would be much more familiar to Tree than to US&S, I'm afraid... There is a big difference between 'clear' in this sense and 'clear board', somewhat like the difference between 'taking your girlfriend out' and 'taking out your girlfriend'...
NDG Overmod "Microsleep detec-ted. Charging.... CLEAR!" You mean it reads Signals, Too??
Overmod "Microsleep detec-ted. Charging.... CLEAR!"
"Microsleep detec-ted. Charging....
CLEAR!"
You mean it reads Signals, Too??
No -- this is a meaning that would be much more familiar to Tree than to US&S, I'm afraid...
There is a big difference between 'clear' in this sense and 'clear board', somewhat like the difference between 'taking your girlfriend out' and 'taking out your girlfriend'...
Train crews have to be qualified in basic first aid. As part of that training we are shown how to properly use an AED, though they are not yet provided on locomotives.
I wonder if that qualification will mean we will be expected to repair those seats ourselves when they inevitably break down.....
York1My first thought was April Fools. But if it's a joke, they sure fooled the news people! https://www.mercurynews.com/2020/04/01/san-pedro-engineer-suspected-of-intentionally-derailing-train-near-usns-mercy/ https://abcnews.go.com/amp/US/engineer-allegedly-crash-train-usns-mercy-los-angeles/story?id=69926172
https://www.mercurynews.com/2020/04/01/san-pedro-engineer-suspected-of-intentionally-derailing-train-near-usns-mercy/
https://abcnews.go.com/amp/US/engineer-allegedly-crash-train-usns-mercy-los-angeles/story?id=69926172
Check out the 0:57 video and photos in the reports linked by York1 above (thanks!) - I think they'll answer most of your questions.
'Measuring' from a Google Maps satellite view, it looks to me like he got about 290' - call it 100+/- yards - mostly on pavement. Looks like what stopped him was a strip of dirt/ sand running at a diagonal - which weirdly enough, might have been a former trackbed! (Notice what appear to be rails/ remnants of a grade crossing of Regan St. directly ahead of the loco and in line with that strip.) It appears he dragged a well car with a single container along with him, which kept on going a little bit further and wound up alongside and parallel to the loco. Looks like it got stuck in the trackbed area, too - wonder if the container was empty? In the aerial view at this page (linked from the Mercury News article above) - https://www.dailybreeze.com/2020/03/31/train-derails-in-san-pedro-causing-leak-but-no-injuries-reported/ - or from a Google Maps satellite view, it shows a bumping post at the end of the track in the middle of the Knoll Drive loop - N 33.7502 W 118.2808 (without any middle reinforcing rails, not that they would have made a difference). From said Google Maps view, it looks like he went pretty much straight, maybe curving a little bit to the right. What's scary is that if you look on the western side of the trackbed where the loco wound up, there's what looks like a complex of big UG pipes and some valves - hope those aren't high pressure gas or petroleum of some kind, or there could have been a real disaster!
From having seen a lot of derailments in paved areas, the wheel-pavement dynamics depend a lot on the paving structure, and what's underneath it. As Overmod said, it depends on how far the wheel sinks into the pavement. But little weight is supported by the flanges - it's the tread that carries most of it. If the paving is reasonably thick and solid, you'd be surprised how little the wheel sinks in - once the wheel sinks in enough so that the full width of the tread is engaged and the contact area expands to about a foot long, it may not go any lower than that - say, 2'' - 3". But once it hits that soft spot, it'll sink up to the truck frame.
As to direction, a body in motion tends to stay in motion in the same direction. Here, as the front wheels of each truck leave the rails, the rear wheels are still constrained by the rails, so the front wheels won't wander much - they're also kept in alignment with the track direction by the center pin or suspension. After that, the same principle applies - "rinse and repeat", or like an arithmetical progression - the rear wheels running in the groove effectively steer the front wheels to go straight ahead.
Back to work now.
- PDN.
Overmod Personally, I'm holding out for single-man crew... with three-view inward-facing telescreen monitoring and steerable exawatt-sec pulsed laser enforcement. Taser prongs through the seat cushion to ensure prompt disablement upon detection of deleterious or deprecable control movements. Sometimes technology does have answers, even when Jove nods.
Personally, I'm holding out for single-man crew... with three-view inward-facing telescreen monitoring and steerable exawatt-sec pulsed laser enforcement. Taser prongs through the seat cushion to ensure prompt disablement upon detection of deleterious or deprecable control movements. Sometimes technology does have answers, even when Jove nods.
https://www.youtube.com/watch?v=g6PBtPYb9DE
Just missing the taser prongs.
I would opine that the dirt/gravel was his undoing. Had the area all been paved, he would have gotten much further. However, if there is curbing in the parking area he would soon have entered, that may have served to stop him, or deflect him if he hit it at a slight angle.
BaltACDYou can train a steer, but you can't steer a train.
Well, technically you can, just not from inside it while running from the cab.
As I recall, the Canadians were prepared to 'steer' their unit if needed, either by using boards to deflect the truck at the wheels or by banging laterally on the truck frame until it turned 'back'. People "steer" trucks all the time when doing re-railing, and that would include any 'correction' for misaligned levers in a steerable truck before starting the process of actual rerailing.
It might also be possible for someone intending to undertake this kind of 'terrorism' to make something to limit truck pivot, or even to rig up some kind of cable system to pull the truck frame in yaw -- the running side resistance to turning the leading axle of a Flexicoil C truck in this situation probably being comparatively little, and the angle of 'steering' correction perhaps slight over time. Let's hope the motivated remain relatively ignorant of this sort of thing...
You can train a steer, but you can't steer a train.
Never too old to have a happy childhood!
EuclidThe pavement also retained enough solid structure to suppor the load as track rails do.
For comparison, go back and look at the stories here about the Canadian use of a diesel-electric of reasonably comparable size as an emergency generator -- it was run on its own wheels a fair distance on asphalt, not cement, paving without materially impeding its ability to run. The substantial damage to actual paving, and probably subgrade, would have been great, but the relatively large wheel diameter compared to the extent of flange and tread 'penetration' would assure reasonably good motion 'on the level' -- you could even calculate the effective resistance for rolling 'up and out' of the compressed groove just as you can for the deformation of pneumatic tires (see for example the interesting discussion for the original Audi Quattro that at speeds above around 50mph the all-wheel drive was more efficient than 'pushing' the steer tires, for related reasons)
But this is not the same thing as 'supporting the load as track rails do' except for the brief exception, and then only incidentally and technically, of flange-bearing frogs and crossovers. When running on track, the contact patch for weight-bearing is supposed to be limited to a portion of the coned tread, with some involvement of the flange fillet on curves. Very little of the flange force would go into weight-bearing, even as a resultant through the suspension.
When running off-pavement, a substantial amount of the load is in flange-bearing; only when the flanges have cut fully into the substrate will the tread progressively come into contact; one can expect that the effective "contact patch" will be an equilibrium between the deformed subgrade's shape and the portion of flange and wheel contacting it, and if the locomotive has the power (low speed or high!) to roll itself out of that depression (the forward end, of course, distorting and flattening itself, rather than making a 'lip' that the engine has to overcome like the cuts made via excessive wheelspin) it can and will continue to move.
Meanwhile, modern power with 'centerless' trucks has inherent centering in the secondary suspension -- it would be interesting for Dave Goding, who is now participating in an active thread elsewhere here, to comment on precisely what the effect of trying this stunt with an HTCR truck under power might be, as I suspect the relatively-unguided kinetics of the lever steering to be metastable when not guided by wheel-rail interaction. The rebuilt locomotive might well have active restoring force in its yaw damping -- this would likely not be difficult to research from the rebuilder's records. In any case the practical force causing the truck to yaw would be related to the lateral area in penetration ... which would seem to me to be remarkably small, except when negotiating an angled change of resistance (as, for example, when going from a paved parking lot onto dirt at some skew angle, or encountering a curb or drainage ditch at an angle).
The video in any case may show if there was progressive yaw of the trucks, and the extent of any 'curving' especially if the engine were being driven at any point by the momentum of the consist (including any remaining on the rails and hence with higher effective inertia to be transferred)...
I conclude that the wheels running on the road pavement broke into it enough to create a form of gooves that acted like track "rails" for guidance. The pavement also retained enough solid structure to suppor the load as track rails do. If it were not for the cut/crushed grooves made in the hard pavement, the trucks would not have had any guidance, and thus would have pivoted and sent the direction of the travel into chaos.
I don't know how fast he was going, but cutting grooves would have produced a lot of friction. Probably, he had the engine applying power at the time. They say they have a video of this. It would be interesting to see that.
OvermodTaser prongs through the seat cushion to ensure prompt disablement upon detection of deleterious or deprecable control movements.
I know a few guys that would probably be into that.
It's been fun. But it isn't much fun anymore. Signing off for now.
The opinions expressed here represent my own and not those of my employer, any other railroad, company, or person.t fun any
Murphy SidingWhen I look at Google Maps, the end of our spur at work is 259 yards from my desk.
With apologies to Patrick Henry- I've been reading this wrong. The train didn't go 250 yards past the derail. It stopped 250 yards short of its intended target. Does anyone know how far it traveled after it left the tracks? When I look at Google Maps, the end of our spur at work is 259 yards from my desk. How much speed do you think this guy built up before his trip into the parking lot?
tree68What happens when they're in it together?
Faster targeting slew and a higher rep rate/duty cycle.
Electroliner 1935 Now could this be a cause to insist on a two man locomotive crew requirement to prevent rogue operation?
Now could this be a cause to insist on a two man locomotive crew requirement to prevent rogue operation?
What happens when they're in it together?
tree68And, like most legends, there may be a sliver of truth involved.
From what I read, they did in fact devise a covert plan to suspend the constitution (under certain conditions).
Isn't that enough? The reality that the government thought enough of that plan to keep it a secret is somewhat of a red flag to me.
Murphy SidingAdmit it. You have an Area 51 T-shirt and commemorative hat, don't you?
I have contempt for sheeple....make of that as you wish.
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