Beyond that, even if were smooth, I’d never ride it. I’m too claustrophobic.
24 thoughts on “The Hyperloop”
humans can only handle about 0.2g’s (or about 2 m/s^2) of acceleration in the up-and-down or side-to-side directions.
Hyperloop certainly has problems, but this is a gross exaggeration.
Many people experience 1g along the Y axis (“side to side”) every night, because they sleep on their sides.
The real problem is not the magnitude of g forces, but the variability and frequency. That’s what will make people sick.
Variability and frequency and unexpectedness, with no windows. I’d never be able to handle it. I can get car sick if I’m not driving, unless I’m looking out the window.
I think they’ll need synthetic windows (video screens) to provide visual cues.
I don’t think I’d want to look out the window at things closely flying by at 800 MPH.
No need to. With synthetic vision, they could just as easily give you the illusion of being at 60,000 feet. Or on Mars. (This is Elon we’re talking about, so probably Mars. 🙂
But that wouldn’t line up with the sensations. It would be as bad as not having a window, from a motion-sickness standpoint.
Why not? The g-forces depend on your flight path, not your altitude. There’s no reason you couldn’t be making the same maneuvers at 60,000 feet. Or you could go in the opposite direction and be flying through savage Pellucidar. 🙂
I’m all for alternative forms of accessible, efficient transportation, particularly if it means not having to endure the horrendous experience of modern airports and airport security.
Please raise your hand if you think that, in a society that includes the Patriot/FREEDOM Act and TSA, a transportation alternative like the Hyperloop wouldn’t be subject to the same sort of frisking procedures that are prevalent in our air travel, especially at the speeds being proposed.
*looks around*
Thought so.
Which brings up two points:
1) How has the paranoia of terrorism left the Acela free from major TSA hassles?
2) If there isn’t enough of a threat to Acela and other forms of long-distance mass-transportation, why do we still put up with having the TSA at the airport? Is it because planes can be taken off-course if hijacked but a train cannot? The loss of life for the passengers is still a risk, as is the loss of use of the train/tracks for an extended period of time after an investigation. Why do plane travelers still receive such harsh treatment?
It’s because a hijacked aircraft is a WMD.
That’s defining WMD way, way down. A well-placed truck bomb could kill thousands; are trucks WMDs too?
If a Hyperloop is ever deployed the decision to require or not require TSA screening would be made for reasons other than a simple cost/benefit calculation, just like the post-9/11 decision to intensively screen airline passengers. A terrorist incident on a Hyperloop would greatly increase the odds of a screening requirement, whether or not screening would have prevented the incident, and whether or not it is likely to prevent future incidents. Humans aren’t good at responding to remote-but-spectacular risks (see also Rand’s work on space safety). We want safety, but more than that we want the feeling that we’re doing something to make us safer, even if it isn’t.
A well-placed truck bomb could kill thousands; are trucks WMDs too?
Truck bombs are. Crashing a fully fueled airliner is more destructive than a truck bomb.
Wow, that law defines WMD down even further. If “any weapon that is designed or intended to cause death or serious bodily injury through the release, dissemination, or impact of toxic or poisonous chemicals, or their precursors” is a WMD, then a syringe of cyanide is a WMD. The M in WMD seems to have vanished entirely.
Yes, I agree, actually. Not sure how US code aligns with international definitions.
1) How has the paranoia of terrorism left the Acela free from major TSA hassles?
Trains have to stray on the tracks or they won’t go very far. While airplanes can be directed basically anywhere. Also electric trains damage would be mostly the kinetic impact, the airplanes are loaded with fuel which is totally different.
Huh; I hadn’t even thought of people getting nauseated, mostly because I hadn’t read a description that good before (or I didn’t read it well if I did roam my eyes over one).
How did the Concorde overcome the problem?
Why would a Concorde have that problem? It’s not a matter of speed, it’s a matter of varying accelerations.
Sloppy of me not to have thought that one through; airplanes don’t have to change course as sharply as trains.
change that “mostly” to “maybe,” eh.
I get motion sick in a car on a twisty road, but I have never been affected while riding a motorcycle. The difference is that on a bike, all the accelerations are down, without Y-axis accelerations. Similarly, an airplane in smooth air can turn without upsetting the passengers by banking, and here again the accelerations are all body-centric down. You do want to limit the eyeballs-up accelerations though. So the jitter motions are handled by careful civil engineering in pylon placement, and the longer wavelength motions by banking the turns. ….. until the next earthquake or vandal attack.
Unless you’re riding on the back, the other difference on the bike is that you’re in control. For example, aerobatics as a pilot are a different experience than as a passenger.
Did the author even read the paper Elon wrote?
The paper described the proposed path and discussed that the top speed at any particular point is limited by the curve radius and the max g force felt by the passengers and that that force will be “down” due to the banking of the vehicle in each curve. The higher frequency “noise” (variations in tube curvature, dynamic vehicle motions) may be more of a problem . I think the sharpest curve was actually the “pull up” to start climbing the Grapevine at the south end of the San Joaquin Valley.
Thankfully, not all forms of transportation need to be comfortable to everyone. Some people ride motorbikes and fly Cessnas, others would never get in either. If a Hyperloop is every built, probably at government expense, and it lives up to the promises (big if!) there will be plenty of people willing to use it.
I’ve commented before that Hyperloop makes more sense as a high speed package transport service, say between FedEx hubs. Packages can fit in smaller vehicles, withstand more brutal acceleration, and don’t have to be provided with air. The last consideration means the tube can be filled with low pressure water vapor, which has a higher sound speed than air.
humans can only handle about 0.2g’s (or about 2 m/s^2) of acceleration in the up-and-down or side-to-side directions.
Hyperloop certainly has problems, but this is a gross exaggeration.
Many people experience 1g along the Y axis (“side to side”) every night, because they sleep on their sides.
The real problem is not the magnitude of g forces, but the variability and frequency. That’s what will make people sick.
Variability and frequency and unexpectedness, with no windows. I’d never be able to handle it. I can get car sick if I’m not driving, unless I’m looking out the window.
I think they’ll need synthetic windows (video screens) to provide visual cues.
I don’t think I’d want to look out the window at things closely flying by at 800 MPH.
No need to. With synthetic vision, they could just as easily give you the illusion of being at 60,000 feet. Or on Mars. (This is Elon we’re talking about, so probably Mars. 🙂
But that wouldn’t line up with the sensations. It would be as bad as not having a window, from a motion-sickness standpoint.
Why not? The g-forces depend on your flight path, not your altitude. There’s no reason you couldn’t be making the same maneuvers at 60,000 feet. Or you could go in the opposite direction and be flying through savage Pellucidar. 🙂
I’m all for alternative forms of accessible, efficient transportation, particularly if it means not having to endure the horrendous experience of modern airports and airport security.
Please raise your hand if you think that, in a society that includes the Patriot/FREEDOM Act and TSA, a transportation alternative like the Hyperloop wouldn’t be subject to the same sort of frisking procedures that are prevalent in our air travel, especially at the speeds being proposed.
*looks around*
Thought so.
Which brings up two points:
1) How has the paranoia of terrorism left the Acela free from major TSA hassles?
2) If there isn’t enough of a threat to Acela and other forms of long-distance mass-transportation, why do we still put up with having the TSA at the airport? Is it because planes can be taken off-course if hijacked but a train cannot? The loss of life for the passengers is still a risk, as is the loss of use of the train/tracks for an extended period of time after an investigation. Why do plane travelers still receive such harsh treatment?
It’s because a hijacked aircraft is a WMD.
That’s defining WMD way, way down. A well-placed truck bomb could kill thousands; are trucks WMDs too?
If a Hyperloop is ever deployed the decision to require or not require TSA screening would be made for reasons other than a simple cost/benefit calculation, just like the post-9/11 decision to intensively screen airline passengers. A terrorist incident on a Hyperloop would greatly increase the odds of a screening requirement, whether or not screening would have prevented the incident, and whether or not it is likely to prevent future incidents. Humans aren’t good at responding to remote-but-spectacular risks (see also Rand’s work on space safety). We want safety, but more than that we want the feeling that we’re doing something to make us safer, even if it isn’t.
A well-placed truck bomb could kill thousands; are trucks WMDs too?
Truck bombs are. Crashing a fully fueled airliner is more destructive than a truck bomb.
Wow, that law defines WMD down even further. If “any weapon that is designed or intended to cause death or serious bodily injury through the release, dissemination, or impact of toxic or poisonous chemicals, or their precursors” is a WMD, then a syringe of cyanide is a WMD. The M in WMD seems to have vanished entirely.
Yes, I agree, actually. Not sure how US code aligns with international definitions.
1) How has the paranoia of terrorism left the Acela free from major TSA hassles?
Trains have to stray on the tracks or they won’t go very far. While airplanes can be directed basically anywhere. Also electric trains damage would be mostly the kinetic impact, the airplanes are loaded with fuel which is totally different.
Huh; I hadn’t even thought of people getting nauseated, mostly because I hadn’t read a description that good before (or I didn’t read it well if I did roam my eyes over one).
How did the Concorde overcome the problem?
Why would a Concorde have that problem? It’s not a matter of speed, it’s a matter of varying accelerations.
Sloppy of me not to have thought that one through; airplanes don’t have to change course as sharply as trains.
change that “mostly” to “maybe,” eh.
I get motion sick in a car on a twisty road, but I have never been affected while riding a motorcycle. The difference is that on a bike, all the accelerations are down, without Y-axis accelerations. Similarly, an airplane in smooth air can turn without upsetting the passengers by banking, and here again the accelerations are all body-centric down. You do want to limit the eyeballs-up accelerations though. So the jitter motions are handled by careful civil engineering in pylon placement, and the longer wavelength motions by banking the turns. ….. until the next earthquake or vandal attack.
Unless you’re riding on the back, the other difference on the bike is that you’re in control. For example, aerobatics as a pilot are a different experience than as a passenger.
Did the author even read the paper Elon wrote?
The paper described the proposed path and discussed that the top speed at any particular point is limited by the curve radius and the max g force felt by the passengers and that that force will be “down” due to the banking of the vehicle in each curve. The higher frequency “noise” (variations in tube curvature, dynamic vehicle motions) may be more of a problem . I think the sharpest curve was actually the “pull up” to start climbing the Grapevine at the south end of the San Joaquin Valley.
Thankfully, not all forms of transportation need to be comfortable to everyone. Some people ride motorbikes and fly Cessnas, others would never get in either. If a Hyperloop is every built, probably at government expense, and it lives up to the promises (big if!) there will be plenty of people willing to use it.
I’ve commented before that Hyperloop makes more sense as a high speed package transport service, say between FedEx hubs. Packages can fit in smaller vehicles, withstand more brutal acceleration, and don’t have to be provided with air. The last consideration means the tube can be filled with low pressure water vapor, which has a higher sound speed than air.
Sort of like a very high-tech pneumatic system.