In my experience cruise control is quite variable. I've driven a number of CC-equipped vehicles over the years and they're all great on the straight-and-level roads but get to a corner or a hill and a lot of them can't cope.
That's really baffling. Any Industrial Engineer worth their degree is going to know their way around tuning PID controllers. A half hour of effort, or some automated algorithms, should get easily manage constants good enough for a couple miles per hour. Half a day should get you a pretty good system. I do agree that some CC implementations are downright pathetic, and I just don't understand why they even bother. I had an underpowered Focus as a loner car once, and on an sharp uphill on-ramp near work, I would drop 10mph before the CC took over.
You're missing the point. The driver is going to be viewing that data anyway. Doesn't it make more sense to put that data in the driver's field of view, and at a focal length that makes it less disruptive to use? Maybe if people had their speed readily available in their field of view, they could more reliably maintain speed on the highway. Of course maybe if people just used their cruise control, that wouldn't be a problem either.
Turbine engines run at high power, but low torque. The need significant gearing to be useful for automotive operation, and even then, do not spool quickly enough to have acceptable acceleration. Turbines would work fine as a generator in an electric vehicle, but in a hybrid where the engine remains attached to the drive train, you have every bit the same problem.
Turbines are very compact, and due to their high combustion temperatures, can run on nearly anything. For thermal efficiency, turbines benefit greatly from scale, meaning a small turbine will not be. A small diesel generator is going to operate considerably more efficient than a small turbine. It's a tradeoff whether you have a small, light engine, or a more efficient one.
Roughly 220kPa. One Pascal is one Newton per meter squared, which by happy coincidence puts standard atmospheric conditions at roughly 100kPa. Compare this with the much more difficult to work with imperial value of 14.7psi.
Cape Canaveral is at roughly 28.5 degrees. The Chinese have satellite launch facilities at Jiuquan (39 deg), Taiyuan (38 deg), Xichang (28 deg), and Wenchang on their southern island at only 19.5 degrees. The equator is 40Mm around, so initial speed at the equator would be around 0.46km/s. At 19.5, you have 0.43km/s; 28 is 0.41km/s; 38 is.36km/s.
Now what does all this mean? Low Earth orbit is around 8km/s, plus another 2.5km/s in altitude. That means there's all of a whopping 1% difference in delta-V between an equatorial launch, and one from China's northern launch facilities. Now true, fuel budgets run on exponential functions, and a 1% increase in velocity results in a more than 1% increase in fuel and cost, but it's not going to be the determining factor whether a launch system succeeded or fails.
Orbital plane changes are a completely different matter. The shuttle only has storage room to carry with it enough fuel for a couple degrees difference in plane, but that's because you're traveling 8km/s. It's not like you're in a car or a plane, and can push off something while maintaining your momentum. It all has to be done with thrust, and you have to reduce velocity in one direction, and increase it in another. When you're going a mere 0.4km/s starting from the ground, you only have to add velocity to get where you want to go. That means it is actually more efficient to land and take off again if you want to transition between equatorial and polar orbits.
The laser is no more going to magically distinguish between civilian airliners and incoming hostile attack craft than the missiles used in that incident will.
Oh it absolutely is. A missile can be launched against an unknown blip on the radar, and seek to a kill on its own. A laser must be targeted at a specific weak point, and must remain on target for extended duration. The trial they did caused the outboard motors on the target ship to catch on fire. To take down an airliner, you would have to target the engine long enough for something to weaken and fail, or target the wing long enough to breach a fuel tank. You would need clear visual lock to do it, and you would be able to visually tell "That's an A300, not an F-14".
Some estimates put the outer reaches of the oort cloud, and thus the limits of bodies orbiting our solar system, at the better part of a light year from the sun. So with our little home being over a light year and a half across, the next solar system just four light years away would be a short trip down the block.
Just a minor point, but this was a ramjet, not a scramjet. While similar in basic operation, the scramjet has supersonic flow through the combustion chamber/heat exchanger, while a ramjet is subsonic. It would likely be very difficult to maintain supersonic flow through a heat exchanger. Beyond that, you simply can't get sufficient compression at Mach 3 for a scramjet to function.
By 'major naval vessels' you mean carriers, right? We have nuclear subs because diesel can't run without air. We used to have some nuclear cruisers, but they've all be decommissioned. The old boiler ships were all decommissioned by the early '90s too. The only fighting ships left of any size use gas turbines.
Because there is no such thing as a propellantless propulsion system? The closest you could get would be light, and the thrust you get some shining a laser out the back is negligible. All of our current 'electric drives' function by ionizing a light inert gas, or heating it to a plasma, before propelling it out the back using an electromagnetic or electrostatic field.
In response to one of the remarks in your other comment about the ability to turn the engine off, I doubt that would ever be done until the airplane was safely on the ground. Gas turbine lifetime is measured more in cycles than operational hours. The thermal expansion and contraction from being turned on and off causes more wear than a several hour flight. You would never want to turn the engine off on descent, and risk an extra cycle because of a foul up on the runway or bad weather causing you to loiter or divert.
Interesting concept. Gas turbines scale up beneficially, such that the larger single turbojet core you have, the higher the power density and higher thermal efficiency you get. In concept, there is really little different between a ducted fan and turbofan (or propeller vs. turboprop), besides what powers it. I could see this being beneficial to these smaller turboprop and 'regional' jets, where multiple engines are replaced with a single larger, more efficient turbine generator at the rear of the fuselage. Removal of all that weight out on the wing will significantly decrease the needed structure.
Once you get up to around a 727, power requirements are going to be too high for any single existing generator, and for anything international, you're certainly going to want multiple engines for reliability.
It's a 1.8GHz dual core Atom, paired with low end nVidia graphics. You can pick up a mini-itx board and case with the same specs for $250, and hide it and all the connecting wires behind the TV. Another $50 gets you a wireless bluetooth keyboard you can stuff on the side of the couch, and you have all the same functionality, only without the big clumsy keyboard on your coffee table and wires strung across the floor to your TV. There is literally no worth to this device besides a gimmick.
But you don't need extra power on take off. Even at cruise, big turbofans are still generally running at 80% or better of peak power output. Gas turbines like to run under full load. They're most efficient under full load. You're also looking at supplementing the output of an engine rated at maybe 30MW for a small airliner, to upwards of 70-80MW for a big GE90 on a 777. You're talking about an absolutely huge electric motor and battery to have any meaningful effect.
On large ships, they're used for two reasons. The use of an electric transmission allows them to place the generator and electric motor anywhere they wish. There is no mechanical drive shaft they have to worry about for placement. This makes the ship design more flexible, and the ship maintenance or replacement easier. Second, they are typically used as azimuth thrusters, where instead of a static propeller with a rudder, the propeller is mounted to a pod, and the whole thing can swivel 360 degrees. It means you don't have to contract extremely expensive harbor pilots and tugs when coming to short.
On jet engines, there are no big bulky transmissions, and the drive shaft is all of a couple feet long. The use of an electric drive would do nothing but serve to add huge amounts of weight. Add to the fact that you're looking at an electric motor on other order of 30-80MW to drive these engines, and a generator just as big.
Any clue how this 'hybrid turbo-electric engine' is supposed to work? Jet fuel is a good two orders of magnitude more dense than conventional batteries. Even taking account for projected advances in nanowire batteries, and the inefficiencies of gas turbine engines, you're still looking at kerosene containing several times the usable energy per unit mass than batteries. Weight is everything in aircraft, and fuel already accounts for the bulk of weight in airliners. The only thing I could see this useful for is for taxiing on the runway, powered by the APU in the back of the aircraft, rather than having those big engines needlessly idle for extended duration while waiting for takeoff clearance.
The point is that the well written GUI has to plan for any and every contingency that might happen. You can write a GUI that would allow you to accomplish everything you otherwise could on a CLI, but you're talking an order of magnitude longer development time. It's simply not profitable to do so. You either end up with a similarly priced product with a small subset of the capability, or a similarly capable product for considerable higher cost.
While I do see the GNU blend of 'top', various programs associated with the Linux kernel, and the 'Xorg' server that was not released until 2004, I don't see anything to distinguish from one blend of Linux to the next, unless are you making the incorrect assumption that all Linux is a blend of Ubuntu? I would be more impressed about that old ass computer that has been sitting in storage since the 80's had 2GB of memory.
In the book, they were just using a generic portable spotlight, rated at a couple million candle power, with a UV filter to prevent permanent damage. Of course that filter was for naught when the people you temporarily blind are pilots on final approach.
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In my experience cruise control is quite variable. I've driven a number of CC-equipped vehicles over the years and they're all great on the straight-and-level roads but get to a corner or a hill and a lot of them can't cope.
That's really baffling. Any Industrial Engineer worth their degree is going to know their way around tuning PID controllers. A half hour of effort, or some automated algorithms, should get easily manage constants good enough for a couple miles per hour. Half a day should get you a pretty good system. I do agree that some CC implementations are downright pathetic, and I just don't understand why they even bother. I had an underpowered Focus as a loner car once, and on an sharp uphill on-ramp near work, I would drop 10mph before the CC took over.
You're missing the point. The driver is going to be viewing that data anyway. Doesn't it make more sense to put that data in the driver's field of view, and at a focal length that makes it less disruptive to use? Maybe if people had their speed readily available in their field of view, they could more reliably maintain speed on the highway. Of course maybe if people just used their cruise control, that wouldn't be a problem either.
I have an '03 Grand Prix and often wonder the same thing.
Turbine engines run at high power, but low torque. The need significant gearing to be useful for automotive operation, and even then, do not spool quickly enough to have acceptable acceleration. Turbines would work fine as a generator in an electric vehicle, but in a hybrid where the engine remains attached to the drive train, you have every bit the same problem.
Turbines are very compact, and due to their high combustion temperatures, can run on nearly anything. For thermal efficiency, turbines benefit greatly from scale, meaning a small turbine will not be. A small diesel generator is going to operate considerably more efficient than a small turbine. It's a tradeoff whether you have a small, light engine, or a more efficient one.
You're suffocating all those plants, you environmental terrorist!
Roughly 220kPa. One Pascal is one Newton per meter squared, which by happy coincidence puts standard atmospheric conditions at roughly 100kPa. Compare this with the much more difficult to work with imperial value of 14.7psi.
I have heard songs with the term 'clicks' before.
Even the most hidebound grumpy old granddad who would never utter the word "kilometer" will say "two-liter Coke".
Sure, but if you try to order a liter of cola at a fast food joint, you're going to get spit in your burger.
Cape Canaveral is at roughly 28.5 degrees. The Chinese have satellite launch facilities at Jiuquan (39 deg), Taiyuan (38 deg), Xichang (28 deg), and Wenchang on their southern island at only 19.5 degrees. The equator is 40Mm around, so initial speed at the equator would be around 0.46km/s. At 19.5, you have 0.43km/s; 28 is 0.41km/s; 38 is .36km/s.
Now what does all this mean? Low Earth orbit is around 8km/s, plus another 2.5km/s in altitude. That means there's all of a whopping 1% difference in delta-V between an equatorial launch, and one from China's northern launch facilities. Now true, fuel budgets run on exponential functions, and a 1% increase in velocity results in a more than 1% increase in fuel and cost, but it's not going to be the determining factor whether a launch system succeeded or fails.
Orbital plane changes are a completely different matter. The shuttle only has storage room to carry with it enough fuel for a couple degrees difference in plane, but that's because you're traveling 8km/s. It's not like you're in a car or a plane, and can push off something while maintaining your momentum. It all has to be done with thrust, and you have to reduce velocity in one direction, and increase it in another. When you're going a mere 0.4km/s starting from the ground, you only have to add velocity to get where you want to go. That means it is actually more efficient to land and take off again if you want to transition between equatorial and polar orbits.
In comics you do have some series that go against this like The Walking Dead or Powers, where death is final.
Don't you mean... where death just means you're going to come back to life and eat your friends?
so called "death" is just the beginning of new, glorious life
in the off-world colonies?
The laser is no more going to magically distinguish between civilian airliners and incoming hostile attack craft than the missiles used in that incident will.
Oh it absolutely is. A missile can be launched against an unknown blip on the radar, and seek to a kill on its own. A laser must be targeted at a specific weak point, and must remain on target for extended duration. The trial they did caused the outboard motors on the target ship to catch on fire. To take down an airliner, you would have to target the engine long enough for something to weaken and fail, or target the wing long enough to breach a fuel tank. You would need clear visual lock to do it, and you would be able to visually tell "That's an A300, not an F-14".
Some estimates put the outer reaches of the oort cloud, and thus the limits of bodies orbiting our solar system, at the better part of a light year from the sun. So with our little home being over a light year and a half across, the next solar system just four light years away would be a short trip down the block.
Just a minor point, but this was a ramjet, not a scramjet. While similar in basic operation, the scramjet has supersonic flow through the combustion chamber/heat exchanger, while a ramjet is subsonic. It would likely be very difficult to maintain supersonic flow through a heat exchanger. Beyond that, you simply can't get sufficient compression at Mach 3 for a scramjet to function.
By 'major naval vessels' you mean carriers, right? We have nuclear subs because diesel can't run without air. We used to have some nuclear cruisers, but they've all be decommissioned. The old boiler ships were all decommissioned by the early '90s too. The only fighting ships left of any size use gas turbines.
Because there is no such thing as a propellantless propulsion system? The closest you could get would be light, and the thrust you get some shining a laser out the back is negligible. All of our current 'electric drives' function by ionizing a light inert gas, or heating it to a plasma, before propelling it out the back using an electromagnetic or electrostatic field.
In response to one of the remarks in your other comment about the ability to turn the engine off, I doubt that would ever be done until the airplane was safely on the ground. Gas turbine lifetime is measured more in cycles than operational hours. The thermal expansion and contraction from being turned on and off causes more wear than a several hour flight. You would never want to turn the engine off on descent, and risk an extra cycle because of a foul up on the runway or bad weather causing you to loiter or divert.
Interesting concept. Gas turbines scale up beneficially, such that the larger single turbojet core you have, the higher the power density and higher thermal efficiency you get. In concept, there is really little different between a ducted fan and turbofan (or propeller vs. turboprop), besides what powers it. I could see this being beneficial to these smaller turboprop and 'regional' jets, where multiple engines are replaced with a single larger, more efficient turbine generator at the rear of the fuselage. Removal of all that weight out on the wing will significantly decrease the needed structure.
Once you get up to around a 727, power requirements are going to be too high for any single existing generator, and for anything international, you're certainly going to want multiple engines for reliability.
It's a 1.8GHz dual core Atom, paired with low end nVidia graphics. You can pick up a mini-itx board and case with the same specs for $250, and hide it and all the connecting wires behind the TV. Another $50 gets you a wireless bluetooth keyboard you can stuff on the side of the couch, and you have all the same functionality, only without the big clumsy keyboard on your coffee table and wires strung across the floor to your TV. There is literally no worth to this device besides a gimmick.
But you don't need extra power on take off. Even at cruise, big turbofans are still generally running at 80% or better of peak power output. Gas turbines like to run under full load. They're most efficient under full load. You're also looking at supplementing the output of an engine rated at maybe 30MW for a small airliner, to upwards of 70-80MW for a big GE90 on a 777. You're talking about an absolutely huge electric motor and battery to have any meaningful effect.
On large ships, they're used for two reasons. The use of an electric transmission allows them to place the generator and electric motor anywhere they wish. There is no mechanical drive shaft they have to worry about for placement. This makes the ship design more flexible, and the ship maintenance or replacement easier. Second, they are typically used as azimuth thrusters, where instead of a static propeller with a rudder, the propeller is mounted to a pod, and the whole thing can swivel 360 degrees. It means you don't have to contract extremely expensive harbor pilots and tugs when coming to short.
On jet engines, there are no big bulky transmissions, and the drive shaft is all of a couple feet long. The use of an electric drive would do nothing but serve to add huge amounts of weight. Add to the fact that you're looking at an electric motor on other order of 30-80MW to drive these engines, and a generator just as big.
Any clue how this 'hybrid turbo-electric engine' is supposed to work? Jet fuel is a good two orders of magnitude more dense than conventional batteries. Even taking account for projected advances in nanowire batteries, and the inefficiencies of gas turbine engines, you're still looking at kerosene containing several times the usable energy per unit mass than batteries. Weight is everything in aircraft, and fuel already accounts for the bulk of weight in airliners. The only thing I could see this useful for is for taxiing on the runway, powered by the APU in the back of the aircraft, rather than having those big engines needlessly idle for extended duration while waiting for takeoff clearance.
The point is that the well written GUI has to plan for any and every contingency that might happen. You can write a GUI that would allow you to accomplish everything you otherwise could on a CLI, but you're talking an order of magnitude longer development time. It's simply not profitable to do so. You either end up with a similarly priced product with a small subset of the capability, or a similarly capable product for considerable higher cost.
While I do see the GNU blend of 'top', various programs associated with the Linux kernel, and the 'Xorg' server that was not released until 2004, I don't see anything to distinguish from one blend of Linux to the next, unless are you making the incorrect assumption that all Linux is a blend of Ubuntu? I would be more impressed about that old ass computer that has been sitting in storage since the 80's had 2GB of memory.
In the book, they were just using a generic portable spotlight, rated at a couple million candle power, with a UV filter to prevent permanent damage. Of course that filter was for naught when the people you temporarily blind are pilots on final approach.