<quote><p>Please name one single ex-nazi engineer who was a war criminal.</p></quote>
<p>War criminal, as in committed crimes which classify them as a, "war criminal." Without fail, when they were absorbed by either the US or Russia, their records were expunged. In some cases, where they could not clear their record, they simply disappeared from the face of the earth - meaning received new identities.</p></quote>
Do you really believe this? What makes you think this could be true? Is there any proof, only a hint even, which could support this?
Or are you just reurgitating some old propaganda lies?
It is often conveniently forgotten that much of the first generation of transsonic US jet fighters benefitted hugely from research data obtained by the US from nazi-german aircraft manufacturers as well as the expertise of ex-nazi engineers some of whom were war criminals.
Please name one single ex-nazi engineer who was a war criminal. Only one will do - but I don't expect you will be able to do so. Be so kind and realize that you are also adhering to propaganda, even if it is not the Glenn Beck type.
I know very little about aviation design, other than the vacuum effect of wings. I'm curious why these solar powered electric planes are glider design rather than flying wing design? It would seem you could get more useful cargo space for batteries and significantly more lift surface.
for flying that high, you need to maximize the lift from your wings. Flying wings need to use some of the lift potential for pitch stability, so they will create less lift per wing area. The drag increment from a tail surface is comparably smaller than that of the bigger wing.
In more precise terms, you need to maximize the product of lift coefficient and the square of the Mach number. This product is typically 0.6 for a well designed straight wing and more like 0.4 for a swept flying wing.
In classical Latin, a double negative would be used for ephasizing a point. I would expect that Johnson, being trained in Latin, transferred this rule to English.
when all they do is replacing textbooks with PDFs of textbooks, there is no reason why pupils should advance more quickly. Even throw in all of Khan Academy (www.khanacademy.org/), and the ony difference is they will watch it on a tab instead of a PC - if they watch at all.
How about putting content in which could really enlighten you where dry and outdated paper books couldn't? Just an example: Look at Gapminder (www.gapminder.org/world/)!
But doing this for all topics would be a massive programming job...
What I do expect: After having sold iPads to all early adopters, the industry will now flog tablet computers to a wider audience, and the school market is a logical choice. So this experiment will be labeled as a success, regardless of the outcome.
as an engineer, the absolute goal of zero fatalities sounds misplaced. In the end, this means that any life has an infinite value, and no trade-off with economics is possible.
This is not a technology goal but a marketing catch-phrase. Of course, a Volvo built in 2020 will be involved in traffic fatalities, simply because humans are endlessly resourceful in finding new ways of getting killed, and car buyers will still look for the best value.
in five years, the next iteration of Windows will be an even closer copy of the Mac OS of a few years earlier than Windows 7 is now. Actually, getting MacBooks now will give those pupils the best preparation for the future!
Real world: Employer pays you for your work, and provides you with any work materials. School World: You pay the school in order to do work, and provide your own materials.
the Starship was far from what you claim - with its stall behavior it was highly unsafe and practically impossible to certify. Burt Rutan dazzled Beech with his 0.85 scale prototype and promised impossible performance for the full scale version, which never lived up to those promises.
And airplanes using carbonfiber were flying at least 10 years earlier (http://www.psu.edu/dept/aerospace/sailplane/origins.html). Get your facts straight.
So far, two thirds of efficiency improvement has been gained by the engine makers, not the airframe designers. If those planes are intended for 2035, I suspect that the guys at MIT extrapolated the current engine efficiency a quarter of a century into the future and had already half of the savings pocketed, without having to improve the airframe a bit. Attaching glider-like winks did the rest, easily.
the current booking systems sort the flights in order of flight time, fastest first. So buying and flying slower jets means that you end up not on page one, but way behind the competition. That's why the A 380 had to be designed for a cruise speed of Mach 0.85, quite a bit more than what would have been the optimum speed for efficiency.
acually, the current jets fly at optimum transport performance, meaning that they fly quite a bit faster than the speed at which the fuel consumption per distance traveled is minimal. The idea is that the plane will fly more trips per day, thus earning more money (and eating up more fuel per trip than necessary). On the whole, this is the most efficient use not of fuel, but of money.
A single radar installation can still be fooled, but once a chain of them is networked, detection is rather simple. When the F-117 appeared, algorithms were not capable of making sense of it's unusual radar returns, but today they are much harder to fool.
...(arguably the only software they make is variations of OS X for all their hardware devices).
you seem to forget their iApps, Quicktime, Xcode, the productivity apps like Keynote or the many pro apps for things like movie cutting and picture editing. While Apple's objective may be to boost their hardware sales, the software is a huge part of the company.
iTunes and Quicktime are most likely even running on your PC.
airhouses or air-inflated tents are quite useful as a quick and cheap hall to cover a tennis court or a swimming pool. So the basic idea works, but I wonder what the effects of upscaling will be. If the thing is just supported by internal overpressure, this could be varied to cover snow loads or the lifting power of the warm air inside. But I severely doubt that the 90% savings in the heating bill can be achieved, and the heat loss due to the necessary ventilation (come on - did anyone expect all the residents to get electric cars just for this? And electric heating?) will be noticeable. I guess the best is to try out the idea in incremental steps. Please don't start with Houston - even a 7000 soul village will be too big for the first test.
Isn't the point of protection to absorb the impact? That's why bubble-wrap is squishy. If this instantly turns solid, wouldn't that mean that the g-forces, the energy of the impact is not absorbed by it and is thus transferred to the item inside?
I would guess the point is the load distribution on the laptop. The unprotected laptop will see a spike of load on one point which will easily exceed the strength of it's shell. When enclosed by a solid material, the load will act on a much larger area, and the maximum load will be proportionally lower. The g forces will stay the same, though.
Does anyone know if traffic accident rates have gone up in recent years?
I haven't heard that they have. But if talking on a cell phone, or texting, while driving is really as dangerous as it seems, I would have expected accident rates to rise significantly.
I don't need some statistics - for me it is enough to be able to spot drivers on the phone reliably from their inept driving from 100m (330 ft, for you Americans) afar. That they have a higher likelihood of being involved in an accident is obvious.
I guarantee the first time there is an accident between a manned aircraft and an unmanned aircraft, it will 100% be the fault of the pilot of the manned aircraft but the media will go nuts over "OMG an unmanned aircraft STRUCK a manned aircraft today!!111"
You are on the right track, but got diverted by some hysteria.
Right now, the pilot is eventually responsible, even for technical mishaps (remember, he needs to check the a/c before flight, for a reason!).
If the UAV autopilot screws up, who will be responsible? The programmer who wrote the code? The operator who watched the events unfold? The owner? The ground control guy? Every one of them will refuse to be held responsible, and the whole mess needs to be cleared up before any meaningful civilian UAV operations will begin.
To get back to your hysteria: In the end it will be the lawyers who will most profit from civilian UAV operations!
Have the drone pull a 400G turn until there isn't a threat anymore. Worst case scenario, trigger an explosive to blow it out of the sky.
Who ever rated this nonsense "Insightful"?
The laws of physics don't change just because there is no pilot in the plane to observe them. Higher performance (= climb and turn rate) come at a price. You CAN design an UAV for higher performance, but then it needs big wings and a large engine. Before it can pull 400g, it needs to create lift 400 times it's weight force. And withstand the stresses involved. With current materials and technology, 400g is a pipe dream.
Huh? Why would unmanned craft have slower climb/turn rates than manned craft? Presumably they would be greater, since there are no squishy bags of meat on board that get uncomfortable while pulling a G or ten. Anyone know?
The laws of physics don't change just because there is no pilot in the plane to observe them. Higher performance (= climb and turn rate) come at a price. You CAN design an UAV for higher performance, but then it needs big wings and a large engine.
The UAVs mentioned in the article are meant to stay aloft for long periods of time, longer than a pilot would allow them to. This means they are oversized motor-gliders with a small, efficient engine. And those indeed have lower flight performance than even your average Cessna.
I don't see the problem in this. As long as you give the aircraft a simple AI (planes practically fly themselves anyway), and a pre-set route, they should be fairly predictable. A simple in-the-air navigation system for collision avoidance and you're set.
You're right - as long as all systems work as intended. Please look up how often some part of an airliner fails and multiply by the number of systems ( system = sensors, actuators, you name it). That is where the human pilot comes in. He can correct for the flaw and get the plane down safely. Now consider that your UAV needs to know exacly what to do with any number and combination of systems failures conceivable. Do you want to write that code (and be responsible when it screws up) ?
First, your code has to interpret what happens correctly. Next, it needs to have a strategy what to change to compensate. And then it must be able to continue the flight with reduced functionality. Granted, humans get part of this chain wrong occasionally. But your code will need quite a bit of work and testing before it can match the capability of a pilot.
There are UAV control systems which simply assume what state all systems are in and decide by comparing how well each assumption matches with perceived reality. There are ways of compensating for failures - but this approach scales badly with increasing complexity. Autonomous UAVs will happen, but AFAIK we are not there yet.
Why we need full size UAVs when radio control UAVs can accomplish anything you'd sanely want accomplish without a human at the controls is beyond me.
The full size UAV must be part even of a remotelly piloted one. There must be a failure mode if the radio connection is lost. In military airspace, you either land on a chute or crash in that case. This is not an option in civilian airspace, where people on the ground might be hit. The probability of that to happen must be demonstrated to be below 10^-9 per hour of operation.
Now, be honest. How many of us had our first computer experience with MS-DOS or Windows 3.1? Would the Internet have blossomed into the vast information network it is today without the aid of easy-to-use software from Microsoft? How about Grandma who wants to set up a webcam so she can chat with her grandchildren?
I can answer each and every one of your questions with: Apple did it for me. Replace Bill Gates in your first sentence with Steve Jobs, and you have my agreement. If you want to find a place for Bill Gates, then please add up all his contributions. You will notice that he did bring forward very litte, but held back a lot of possible progress. He *definitely* is in a different class than Linus or ESR.
Slashdot Mirror
<quote><p>Please name one single ex-nazi engineer who was a war criminal.</p></quote>
<p>War criminal, as in committed crimes which classify them as a, "war criminal." Without fail, when they were absorbed by either the US or Russia, their records were expunged. In some cases, where they could not clear their record, they simply disappeared from the face of the earth - meaning received new identities.</p></quote>
Do you really believe this? What makes you think this could be true? Is there any proof, only a hint even, which could support this?
Or are you just reurgitating some old propaganda lies?
Which one is more plausible?
It is often conveniently forgotten that much of the first generation of transsonic US jet fighters benefitted hugely from research data obtained by the US from nazi-german aircraft manufacturers as well as the expertise of ex-nazi engineers some of whom were war criminals.
Please name one single ex-nazi engineer who was a war criminal. Only one will do - but I don't expect you will be able to do so. Be so kind and realize that you are also adhering to propaganda, even if it is not the Glenn Beck type.
I know very little about aviation design, other than the vacuum effect of wings. I'm curious why these solar powered electric planes are glider design rather than flying wing design? It would seem you could get more useful cargo space for batteries and significantly more lift surface.
for flying that high, you need to maximize the lift from your wings. Flying wings need to use some of the lift potential for pitch stability, so they will create less lift per wing area. The drag increment from a tail surface is comparably smaller than that of the bigger wing.
In more precise terms, you need to maximize the product of lift coefficient and the square of the Mach number. This product is typically 0.6 for a well designed straight wing and more like 0.4 for a swept flying wing.
And now you are making things up.
In classical Latin, a double negative would be used for ephasizing a point. I would expect that Johnson, being trained in Latin, transferred this rule to English.
when all they do is replacing textbooks with PDFs of textbooks, there is no reason why pupils should advance more quickly. Even throw in all of Khan Academy (www.khanacademy.org/), and the ony difference is they will watch it on a tab instead of a PC - if they watch at all.
How about putting content in which could really enlighten you where dry and outdated paper books couldn't? Just an example: Look at Gapminder (www.gapminder.org/world/)!
But doing this for all topics would be a massive programming job ...
What I do expect: After having sold iPads to all early adopters, the industry will now flog tablet computers to a wider audience, and the school market is a logical choice. So this experiment will be labeled as a success, regardless of the outcome.
as an engineer, the absolute goal of zero fatalities sounds misplaced. In the end, this means that any life has an infinite value, and no trade-off with economics is possible.
This is not a technology goal but a marketing catch-phrase. Of course, a Volvo built in 2020 will be involved in traffic fatalities, simply because humans are endlessly resourceful in finding new ways of getting killed, and car buyers will still look for the best value.
in five years, the next iteration of Windows will be an even closer copy of the Mac OS of a few years earlier than Windows 7 is now. Actually, getting MacBooks now will give those pupils the best preparation for the future!
Real world: Employer pays you for your work, and provides you with any work materials.
School World: You pay the school in order to do work, and provide your own materials.
non scolae, sed vitae discimus.
the Starship was far from what you claim - with its stall behavior it was highly unsafe and practically impossible to certify. Burt Rutan dazzled Beech with his 0.85 scale prototype and promised impossible performance for the full scale version, which never lived up to those promises.
And airplanes using carbonfiber were flying at least 10 years earlier (http://www.psu.edu/dept/aerospace/sailplane/origins.html). Get your facts straight.
So far, two thirds of efficiency improvement has been gained by the engine makers, not the airframe designers. If those planes are intended for 2035, I suspect that the guys at MIT extrapolated the current engine efficiency a quarter of a century into the future and had already half of the savings pocketed, without having to improve the airframe a bit. Attaching glider-like winks did the rest, easily.
the current booking systems sort the flights in order of flight time, fastest first. So buying and flying slower jets means that you end up not on page one, but way behind the competition. That's why the A 380 had to be designed for a cruise speed of Mach 0.85, quite a bit more than what would have been the optimum speed for efficiency.
acually, the current jets fly at optimum transport performance, meaning that they fly quite a bit faster than the speed at which the fuel consumption per distance traveled is minimal. The idea is that the plane will fly more trips per day, thus earning more money (and eating up more fuel per trip than necessary). On the whole, this is the most efficient use not of fuel, but of money.
A single radar installation can still be fooled, but once a chain of them is networked, detection is rather simple. When the F-117 appeared, algorithms were not capable of making sense of it's unusual radar returns, but today they are much harder to fool.
Do you really think Dr. Shi will tell everyone what he really thinks? He says what needs to be said to come back and not get into trouble.
He is clever enough to have figured that out. You, on the other hand ...
...(arguably the only software they make is variations of OS X for all their hardware devices).
you seem to forget their iApps, Quicktime, Xcode, the productivity apps like Keynote or the many pro apps for things like movie cutting and picture editing. While Apple's objective may be to boost their hardware sales, the software is a huge part of the company.
iTunes and Quicktime are most likely even running on your PC.
you nicely underscored the point with your typos. Many more than necessary, but impossible to predict and not following any pattern.
airhouses or air-inflated tents are quite useful as a quick and cheap hall to cover a tennis court or a swimming pool. So the basic idea works, but I wonder what the effects of upscaling will be. If the thing is just supported by internal overpressure, this could be varied to cover snow loads or the lifting power of the warm air inside. But I severely doubt that the 90% savings in the heating bill can be achieved, and the heat loss due to the necessary ventilation (come on - did anyone expect all the residents to get electric cars just for this? And electric heating?) will be noticeable.
I guess the best is to try out the idea in incremental steps. Please don't start with Houston - even a 7000 soul village will be too big for the first test.
Isn't the point of protection to absorb the impact? That's why bubble-wrap is squishy. If this instantly turns solid, wouldn't that mean that the g-forces, the energy of the impact is not absorbed by it and is thus transferred to the item inside?
I would guess the point is the load distribution on the laptop. The unprotected laptop will see a spike of load on one point which will easily exceed the strength of it's shell. When enclosed by a solid material, the load will act on a much larger area, and the maximum load will be proportionally lower. The g forces will stay the same, though.
Does anyone know if traffic accident rates have gone up in recent years?
I haven't heard that they have. But if talking on a cell phone, or texting, while driving is really as dangerous as it seems, I would have expected accident rates to rise significantly.
I don't need some statistics - for me it is enough to be able to spot drivers on the phone reliably from their inept driving from 100m (330 ft, for you Americans) afar. That they have a higher likelihood of being involved in an accident is obvious.
I guarantee the first time there is an accident between a manned aircraft and an unmanned aircraft, it will 100% be the fault of the pilot of the manned aircraft but the media will go nuts over "OMG an unmanned aircraft STRUCK a manned aircraft today!!111"
You are on the right track, but got diverted by some hysteria.
Right now, the pilot is eventually responsible, even for technical mishaps (remember, he needs to check the a/c before flight, for a reason!).
If the UAV autopilot screws up, who will be responsible? The programmer who wrote the code? The operator who watched the events unfold? The owner? The ground control guy? Every one of them will refuse to be held responsible, and the whole mess needs to be cleared up before any meaningful civilian UAV operations will begin.
To get back to your hysteria: In the end it will be the lawyers who will most profit from civilian UAV operations!
Have the drone pull a 400G turn until there isn't a threat anymore. Worst case scenario, trigger an explosive to blow it out of the sky.
Who ever rated this nonsense "Insightful"?
The laws of physics don't change just because there is no pilot in the plane to observe them. Higher performance (= climb and turn rate) come at a price. You CAN design an UAV for higher performance, but then it needs big wings and a large engine.
Before it can pull 400g, it needs to create lift 400 times it's weight force. And withstand the stresses involved. With current materials and technology, 400g is a pipe dream.
Huh? Why would unmanned craft have slower climb/turn rates than manned craft? Presumably they would be greater, since there are no squishy bags of meat on board that get uncomfortable while pulling a G or ten.
Anyone know?
The laws of physics don't change just because there is no pilot in the plane to observe them. Higher performance (= climb and turn rate) come at a price. You CAN design an UAV for higher performance, but then it needs big wings and a large engine.
The UAVs mentioned in the article are meant to stay aloft for long periods of time, longer than a pilot would allow them to. This means they are oversized motor-gliders with a small, efficient engine. And those indeed have lower flight performance than even your average Cessna.
I don't see the problem in this. As long as you give the aircraft a simple AI (planes practically fly themselves anyway), and a pre-set route, they should be fairly predictable. A simple in-the-air navigation system for collision avoidance and you're set.
You're right - as long as all systems work as intended. Please look up how often some part of an airliner fails and multiply by the number of systems ( system = sensors, actuators, you name it). That is where the human pilot comes in. He can correct for the flaw and get the plane down safely. Now consider that your UAV needs to know exacly what to do with any number and combination of systems failures conceivable. Do you want to write that code (and be responsible when it screws up) ?
First, your code has to interpret what happens correctly. Next, it needs to have a strategy what to change to compensate. And then it must be able to continue the flight with reduced functionality. Granted, humans get part of this chain wrong occasionally. But your code will need quite a bit of work and testing before it can match the capability of a pilot.
There are UAV control systems which simply assume what state all systems are in and decide by comparing how well each assumption matches with perceived reality. There are ways of compensating for failures - but this approach scales badly with increasing complexity. Autonomous UAVs will happen, but AFAIK we are not there yet.
Why we need full size UAVs when radio control UAVs can accomplish anything you'd sanely want accomplish without a human at the controls is beyond me.
The full size UAV must be part even of a remotelly piloted one. There must be a failure mode if the radio connection is lost. In military airspace, you either land on a chute or crash in that case. This is not an option in civilian airspace, where people on the ground might be hit. The probability of that to happen must be demonstrated to be below 10^-9 per hour of operation.
Now, be honest. How many of us had our first computer experience with MS-DOS or Windows 3.1? Would the Internet have blossomed into the vast information network it is today without the aid of easy-to-use software from Microsoft? How about Grandma who wants to set up a webcam so she can chat with her grandchildren?
I can answer each and every one of your questions with: Apple did it for me. Replace Bill Gates in your first sentence with Steve Jobs, and you have my agreement.
If you want to find a place for Bill Gates, then please add up all his contributions. You will notice that he did bring forward very litte, but held back a lot of possible progress. He *definitely* is in a different class than Linus or ESR.