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Comment Re:40 years already been 20%-38% of electricity (Score 1) 280

So, you are saying that government is the problem? I can agree with that.

If coal was regulated like nuclear then we'd be shutting down every coal plant based upon radiation leakage to the environment alone. The level of radiation in Grand Central terminal in NYC is higher than would be allowed in any nuclear power plant control room. Does anyone consider that train station a radiation hazard?

The regulations that nuclear power needs to meet to get a permit in the USA is insanity upon insanity. The rules are arbitrary and based on bad science. If we get some sane rules then we'd get nuclear power going again. Nuclear power is safe, inexpensive (government regulations aside), plentiful, reliable, and as "green" as wind or solar.

Anyone that claims we can have "green" energy but does not include nuclear power is insane, ignorant, or perhaps both. These people will claim that "any day now" solar power will be cheaper than coal, we can store up our wind and solar power in big batteries, and "smart grids" will connect it all. What do we do until this technology comes? I say we use nuclear power. It does everything that people claim wind and solar will do some day but we've seen nuclear do this already for 40 years.

Unfortunately we'd need to see one new gigawatt scale nuclear power plant go online in the USA every month to meet the demands of retired coal and nuclear plants. It's likely we'd have to exceed that to meet growth demands in the future. The way nuclear power plants are approved now simply cannot match that rate. We need to fix the rules on licensing nuclear power or bad things will happen in the coming decades. What are those "bad things"? Regional brownouts and blackouts, prices skyrocketing, perhaps a deadly failure in a power plant that has been forced to limp along well beyond its designed life span.

I do believe that if we do see prices get high enough, blackouts start to occur, that it will be resolved quickly. People will forget about Fukushima and Three Mile Island when the power goes out in the middle of winter. At that point I expect that we'll do like we did in the 1950s and be able to bring a nuclear power plant on line, from ground breaking to producing power, in 24 months.

It takes 10 years to build a nuclear power plant right now only because we deemed it so. When we no longer deem it necessary to create such delays then things can move quickly.

Comment Re:Well there's your problem (Score 1) 106

In what situation would you find a need to push this car? We're talking about a very rare situation, even rarer than a mechanical parking brake getting frozen while engaged.

I kind of see your point but why would anyone need to push an electric car? What would the destination be? Maybe someone might need to disengage the brakes for a tow but any tow truck I've seen would have the ability to provide 12 volt power with sufficient current and duration to do so. It's also not all that uncommon for a "tow truck" to actually be a flatbed capable of getting all wheels off the ground.

I'm not saying what you propose is impossible, only that it is such an exceedingly rare situation that I do not believe it to be a reasonable case against electric brakes. If we're going there then I can name all kinds of ways mechanical brakes can fail and leave people in a worse situation.

Comment Re:Sounds like a market opportunity to me (Score 1) 224

"Nobody wants a tablet with iPad 2 vintage components in it. "

If that were true then Apple would not feel any motivation to specify that they be destroyed. If Apple did not see them as potentially valuable to competitors then they'd do nothing since it would avoid any friction from potential recycling contractors and also avoid any possibility of bad press if this contractual obligation got out. My guess is that there were many people at Apple that did this math but perhaps did not anticipate all the factors properly because we are talking about it now.

Comment Sounds like a market opportunity to me (Score 1) 224

As much as people are upset about this there is a very logical solution to this, get in the recycling business. I imagine that a lot of people out there can't just get in the recycling business themselves but they have the choice on how they recycle their aged and/or broken electronics. You don't have to send your old MacBook to Apple, find a recycler that will not simply shred it into confetti. A question comes to mind, how did we get ourselves in this interesting situation?

Here's a problem that I see. The government decided that to make sure old electronics did not end up in landfills they forced the manufacturers to accept old devices and have them "recycled". There are many forms of recycling, as made clear in the article, but the government did not specify the form of this recycling and/or did not prevent the manufacturers to place conditions on third party recyclers they hired out.

Seems to me that if we want to see this practice stop then we should remove the requirement that manufacturers recycle their old devices. The problem is the government got involved. Without government getting involved in this the producers of these electronics would not be in a position to shred their competition.

I see more and more examples as time goes on where Ronald Reagan got it right. Government is quite often not the solution, it is the problem.

Comment Re:Well there's your problem (Score 1) 106

With an electric car the risk is not only low it is nearly non-existent.

To activate the brakes the car has to have had enough charge to propel itself. There is perhaps a very small chance that the car could lose power in the exact moment where it was unable to engage the brake before power to the system was lost. Once the battery is discharged though that car is not moving under its own power, electric parking brakes or not. If it has enough power to move then it has enough power to engage/disengage the brakes.

Every car that is allowed on public roads is required to have two independent braking systems. In the case of a failure of the parking brake to activate there is another system. Loss of power likely also means loss of power brakes but that diminishes braking power based on pressure applied to the pedal, not complete loss.

My first response to reading about electrically activated brakes was much like yours. After thinking it through though I don't see this as any more problematic than any mechanical system.

Comment Third party? (Score 1) 106

"Tesla estimates that about 2 percent of the vehicles recalled contain the improperly manufactured gear. It should be noted that the parking brake assembly is from a third-party supplier, as well."

If this is from a third party then it seems probable that this assembly was offered to other car makers. Have other car makes used this assembly? This is a voluntary recall from Tesla so it is possible that this is left unresolved by anyone with a car made by someone other than Tesla and has electrically activated parking brakes.

I'm sure Tesla will get some bad press from the recall but I imagine that this is much less damaging to their reputation than news reports of Tesla vehicles being unable to move due to parking brakes locking up on drivers.

Comment Re:Well there's your problem (Score 1) 106

My truck has an automatic transmission and yet I use the parking brake quite regularly. Do I still fit in your two "buckets" of people?

Someone might ask why I bother with the parking brake if I have an automatic transmission. Where I live there are quite a few hills and if I park on a hill and fail to engage the parking brake this puts pressure on the transmission such that it can take an "uncomfortable" amount of force to shift out of park. What do I mean by "uncomfortable"? I mean in that it's enough force that I have to wonder if I could damage and/or wear some part prematurely. I also don't like the idea of the possibility that there is considerable and constant force on the transmission while it is parked, and if there is a failure in the transmission my truck could roll down a hill and damage itself, something else, or SOMEONE else. With the transmission in park, and the parking brake engaged, I'm quite certain that my truck will not roll downhill excepting some highly unlikely event.

I also make an effort to point the steering wheel in a way that if my truck should roll down the hill it will do so in a way to minimize damage. This usually means pointing the front wheels towards the curb so that if my truck rolls downhill it will hit the curb first.

Some might call me paranoid but I think this is just good practice. It takes only a split second to engage and disengage the brake and I've been doing this for so long I don't even think about it, it's reflex.

Comment Re:Alternate hypothesis (Score 1) 173

Many popular music artists will freely admit they are not musicians. Lionel Ritchie admitted in an interview on how he could barely play the piano. In music videos he'd be shown playing the same chord over and over as the camera zoomed in on his face and then he'd start to sing, and someone else would play the piano from there. I saw a TMBG concert and Flansburgh made a joke that he didn't really know how to play guitar, and ever since then when I see him perform I can't help but notice how little he actually plays. Jim Morrison considered himself a poet, not a musician. I could go on.

Point is that to be a successful person in the music business does not mean one must know how to play a musical instrument. I'm not saying I'm any expert on this but I got a few peaks behind the curtain, literally and figuratively, over the years. Music is not my profession, I just ran into a lot of people that did things behind the scenes. My brother was a stage hand in a college town, I've taken music lessons from professionals, I got to talk to a lot of musicians, and I like to read history. There are many aspects to selling music, and having a pretty face and knowing how to dance certainly helps.

If your experience with music is from Super Bowl half-time shows and performances from awards ceremonies then I can see why you'd think that concerts are just backtracks and dancing. If you go to a real concert you will see the people perform in real time, and often not a lot of dancing.

People that don't have any real ability and rely on backing tracks may find success but it will be fleeting, just ask Milli Vanilli. Music fanatics will spot a fake pretty quick. Milli Vanilli got away with their ruse for only two years and only with considerable effort. I believe a lot of people learned from that and that is a trick that can lead to financial ruin.

I believe the music business is pretty honest with it's consumers. They might exaggerate someone's ability with a guitar when they sing but they don't call that person the guitar player, they call them the singer. If you are going to concerts and are disappointed that all you get is a dance routine set to the band's latest album then stop going to those concerts. It's not that hard to find real musicians in any city in the USA. I've lived in small towns in the Midwest most of my life and if I want to see a "real" concert then I can on a regular basis.

Comment Re:Astronavigation and knots (Score 1) 86

That is a very likely story behind the use of the word "knot" as a measure of speed. How a "knot" became defined as a minute of latitude per hour is another matter.

I suspect the use of knots in a rope to measure speed was one thing, and the measure of speed by minutes of latitude per hour was another thing, which converged in meaning over time. I don't know the answer and it's possible no one does.

Comment Re:So what's the range of the full size prototype? (Score 1) 86

Might we someday end up with batteries that are as energy dense (volume and weight) -- certainly that is the hope, just not necessarily reality as yet.

I'm pretty sure that will never happen. That is assuming one defines a battery as we understand it currently, a device that stores electric energy directly as a reversible chemical process. What some people call "batteries" are really just capacitors or fuel cells that have a form/fit/function similar to a battery, and even then I'm not sure we'd see anything better.

Jet-A is an incredibly dense energy source that is a liquid at temperatures and pressures that we will commonly run into. This means it can be stored in something as inexpensive, durable, and lightweight as a steel tub or plastic bottle. It has other nice properties such as it's ability to lubricate and preserve metal parts, and that it's relatively difficult to ignite in case of an open flame.

Jet-A is really hard to beat as a fuel.

Comment Re:So what's the range of the full size prototype? (Score 3, Interesting) 86

The batteries would be a wash if you removed one of the engines and less fuel might offset a heavier generator.

That does not seem likely to me. We design aircraft with multiple engines because it provides redundancy and convenience. Two engines are nice because they can derive power from a shared energy pool, the fuel tanks. With a single engine and a battery pack the loss of the engine means losing access to that pool of energy that is the fuel.

Then there is the issue of charging up that battery. Given proper infrastructure the battery could be charged from grid power. In the case of remote locations, or emergencies, the grid power cannot be relied upon. In which case the electricity would come from diesel generators and the like. In that case the batteries would be charged from a generator as part of the ground crew tools, have to be charged from the engine on board using fuel while idle on the ground, or whatever. The energy would still come from the fuel but with the additional losses of charging and discharging the battery.

If a battery-turbine "hybrid" plane did suffer a failure of either power plant, the turbine or battery, then parts for both would have to be kept on hand. With a two engine craft a power plant failure would typically mean replacing the engine with one that can fit in either spot. It's the low replacement part count that keeps aircraft like the A-10 in the air. The A-10 has very few parts that are unique to left or right. There is no "left wing" or "right wing" there's just "wing".

A friend of mine worked as ground crew servicing F-16 jets, which has one main engine. A twin engine craft can use power from one engine to restart the other, but a single engine craft does not have that option. There is a battery on board of the aircraft but that is only for navigation and communication. If the engine is in need of restart in the air, or with a lack of proper ground equipment while on the ground, there is a small powerful engine on the plane that can start the main engine. I recall that it runs on hydrazine but I'm not sure about that. Even so there is only enough fuel for the auxiliary engine to attempt two or three engine starts.

The point is that even with an electric drive system the poor energy density of batteries do not make sense to drive the engines. Electric passenger commuter cars can get away with using battery storage because ranges are short and charging stations are easy to find. Not having to get airborne, or stay afloat, helps considerably too.

Comment Astronavigation and knots (Score 1) 86

I'm not a professional map reader by any means but I did some work on electronic navigation systems and I like to read about history, because of this I read up on how navigation is done now and how it was done before.

I suspect that measuring speed in knots came in common use once people understood astronavigation. Common trade routes were primarily along longitudinal lines, such as along the American coasts and from Europe to Africa. Knowing your speed in knots would have a lot of meaning in that case. By knowing your latitude at a given time in the past and comparing that to your current latitude then speed can be approximated. Knowing the time is also fairly trivial even before modern time pieces so long as one did not deviate far from a given longitude.

When it comes to radio navigation the units used there would lead one to use kph to indicate speed. Radio wavelengths are commonly measured in meters. Angular measurements would be in degrees and minutes still but that does not mean it translates well to the degrees and minutes used to indicate latitude and longitude on a map. Distances and directions still would though.

When it comes to critical navigation failures on land, sea, or air it is not uncommon to fall back to astronavigation. However this does not necessarily mean one would also fall back to using knots in measuring speed. Kilometers, minutes of arc, and such are still very useful and would translate well to a map laid out in kilometers.

Knots may fall out of common use in time but it's got a lot of inertia behind it. A lot of that inertia will come from trade routes still being largely oriented north-south.

Comment Re:You dumbfuck (Score 3, Interesting) 86

A knot is defined as one minute of geographic latitude in one hour, or a close approximation of it.

My understanding is that this is an accepted means of indicating speed is because it makes for easy translation of speed and distance on common maps. Certainly tradition plays a part but this part it plays is because of how people kept time and measured distance. Since we still use minutes of latitude and hours in tracking distance and time we still use the knot to translate between them.

When traveling at greater heights and distances then other units become more convenient, like mach number and kph. Even then the conversion to knots is almost inevitable since the world is laid out in minutes of arc on most any map you'll find.

Comment Re:So what's the range of the full size prototype? (Score 1) 86

As this is a tilt rotor aircraft I would think that a more appropriate analogy would be with the V-22 and aircraft like it. Or even with other VTOL aircraft, such as the V-8 (Harrier derived craft) or F-35B (lift fan variant).

What we've had before were two classes of aircraft, helicopters and airplanes. Helicopters could take off and land on small areas but were slow and fuel hungry. Airplanes used much less fuel per mile traveled and/or mass carried but at the cost of needing a large take off and landing area.

Tilt rotor craft allowed one to create an aircraft that had speed, small take-off/landing area, and fuel efficiency, but at a cost of complexity and reliability. The V-22 is a very well liked aircraft but it has high maintenance costs from its complex gearboxes. If this experiment is successful then the cost penalty for VTOL airplanes can become very very small. It's not likely to make traditional helicopters and airplanes obsolete but it will replace many of them in many cases.

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