One of the articles I read today says that the Army has already got that going. They are already firing 'smart' projectiles from howitzers and other large guns, and I would think that the accelerations are equivalent.
Just idly thinking about this, solid state electronics can take a lot. When you drop your watch on a concrete floor it may experience 700 G deceleration on impact, at an arbitrary angle.
But it's a function of time. Since the projectile traverses the distance in, e.g., 1/5 the time, the gravitational drop (I forget the real term) will only be 1/5 as much.
There are several advantages to railguns for the Navy, in lethality, cost-per-round, how much ammo you can carry, and overall safety.
Lethality - the kinetic energy of a 'passive' round at these velocities is equivalent to or greater than an explosive round (though I would think it might not be all that useful in all circumstances - just flying through some softer materials instead of blowing them up). As the videos show, the 'kill' factor is substantial. The projectiles are also much less affected by gravitational drop and windage - I would think proportional to the velocity - so accuracy will be better. The higher velocity also allows for firing at much longer range - up to 200 miles vs. 30 for the latest 155mm round.
Cost-per-round - while not as cheap as lasers (the laser about to go through sea trials has a cost of about $1 per shot), these systems should have a cost-per-round an order of magnitude cheaper than the big artillery presently in use. (I just read that 155mm shells cost $50,000 each.) It's much easier, cheaper, and safer to build a solid chunk of tungsten or whatever than a huge shell, especially when the savings in transport and necessary safety systems and procedures is taken into account.
How much - the propellant takes up a lot of space, must be stored in special containment that takes up more space. All of that space can be used to store actual projectiles instead, possibly multiplying the number of rounds available by a factor of 5 to 10. Add to that the the higher kinetic energy allows a smaller projectile to be equally effective, which means you can increase the number even more.
Safety - this eliminates the problem of ammunition exploding either in the ship that will use it, or the supply ship. There are many instances of a single 'lucky' hit on a ship that happens to penetrate the ammunition magazines, whereupon that explosion rips the ship in half. The explosives used in ammunition are also toxic. Removing the propellant greatly increases the survival probability in the event of a hit, and eliminates the probability of an unfortunate accident sinking the ship. This also means the supply ships are safer and can deliver much more ammunition in one trip.
It is _possible_ to land reasonably safely in the ocean. It requires a lot of skill and luck. Basically the plan has to orient in the same direction as the swells, slow down to just above stall speed (still about 150 knots IIRC), take a nose high attitude to prevent cartwheeling, and basically 'land' as slowly as possible, preferably picking the moment of contact on a wave peak. This of course works much better when the water is flat, which it rarely is in the southern Indian Ocean and the Southern Ocean - read up on the "Roaring Forties". Even once you have 'landed', the high waves have enough force to start stressing the plane to the breaking point, and as soon as the doors open the waves are going to play hell with rafts and people trying to get out on them. It's not quite like boarding a raft in a hurricane, but it's close.
There was a sci fi story that went like that - but I think it was people from the future, who needed the bodies for some reason. So just before everyone died they pulled the real bodies and substituted fake 'meat' bodies that, after the plane burned etc., would be easily assumed to be real.
A friend of mine used to work for a company that built satellite receiving antennas, working on the software for the mounts. One of the things they would do is peruse the published satellite ephemera - I think each satellite's data was 80 points - and look for places where no satellites officially existed. Then they'd point their antenna there, and bingo! They found several military satellites that way.
A British airliner that disappeared a few miles from the airport back in 1951 was recently discovered. Its next-to-last messages (via Morse Code) were that it was close to landing. Its fate was unknown until 1998. And that was on land. The area to be searched, given the best possible scenario with present data, is IIRC 22,000 square miles, about the size of Rhode Island, Massachusetts, Connecticut, and New Hampshire combined - about 1/3 of New England or about the same as Latvia or Lithuania, or 2/3 of Scotland. This is a much harder problem than the Air France jet of a few years ago, where they knew within a small range where the plane was likely to be.
I don't think it's possible for the pilot to shut off the flight recorders, at least without climbing all over the airplane. They are independently powered and situated at the back of the plane. They may only be accessible from outside the plane - I don't know this for sure.
To add to that, that area of ocean has about the worst conditions for ships, planes or helos. The "Roaring Forties" is not named that for nothing. A typical 'nice' day there will have 30 to 60 knot winds and 20 foot seas, plus a lot of fog, clouds and rain, air temps in the 0C to 10C range, and sea temps of 0C. Of course, if that's too balmy, there's always the Furious Fifties and Screaming Sixties. The Indian Ocean gradually becomes the Southern Ocean, which is the only ocean that has no barriers to its west-to-east current to slow it down, and the air above it is the same. The speeds are also multiplied because this is the air current that is balancing the east-to-west flow at the Equator, and also the rising air over the Equator sinks back down around the 30th parallel. But the circumeferential of the Earth at that latitude is about 1/2 that at the Equator, so the air travels twice as fast.
Think of Jupiter, and the tremendous winds generated there and the different bands going different ways - if there were no land masses the winds on Earth would look similar.
Then there's the depth and underwater terrain - the depth ranges from 3000 to 23000 feet (Mt. Everest is 29000) and is reportedly very rugged with canyons etc. It's one of the least explored parts of the global ocean, because of the conditions.
Most of the electronics in the cockpit - radios especially - are decades-old technology. This is in part because of the overlapping and 'rigorous' FAA and FCC standards. If a single component - a resistor, whatever - is changed, the entire unit has to go through certification all over again, by both agencies. This costs perhaps $10 million, and the total sales of that model radio may be 10,000 units, which means the amortized cost of certification is on the order of $1000 per radio. That is direct cost in advance of manufacturing. Back when I was flying, CB radios that cost under $100 had better reception and better voice quality than $3000 aircraft radios.
It is widely stated that Quartz "uses PDF" internally (notably by Apple in Quartz's early developer documentation[5]), often by people making comparisons with the Display PostScript technology used in NeXTSTEP and OPENSTEP (of which Mac OS X is a descendant). Quartz's internal imaging model correlates well with the PDF object graph, making it easy to output PDF to multiple devices.[6]
WRT to OSX, there is history. Back in the days of NeXT, Jobs & co. decided to use Display Postscript for a variety of reasons. A few of the reasons: X back then was huge, ungainly and a total beast to work with using the limited memory and cycles available (The NeXTstation used a 25MHz 68000); their team were not ever going to be able to morph X into an object-oriented platform, which NeXT definitely was; Display Postscript was Adobe's new Hotness; the NeXT folks could write drivers for DP that worked with the Texas Instruments signal processor (TM-9900? I forget), which was truly amazingly fast at screen manipulation; and the X architecture didn't fit well with either Display Postscript or the TM-9900.
In 2001 I had a NeXTstation that I added some memory and a bigger disk to. The machine was by then more than 10 years old. For normal workstation duties, it was faster than my brand new desktop machine due entirely to the display architecture. But compiling almost anything on that 25MHz CPU was an overnight task - I had one compile that ran three days.
... has been going on for almost as long as coinage itself. One of the advantages of paper money (in addition to weight, lower manufacturing cost, etc.) is that it can be harder to forge. Any shmuck with a press can create coins that are hard to distinguish from the real thing. On a larger scale, one of the big problems today with gold is people hollowing out gold bars and filling them with tungsten, or starting with tungsten and wrapping a small amount of gold. These are indistinguishable from the real thing, for the non-expert and even for experts without the necessary equipment (and suspicion).
IANA bitcoin holder, but having looked into the original Nakamoto paper (which is short and much better than any of the derivatives), and discussed this with people who know, the bitcoin methodology or protocol or whatever is with us to stay, and will be used for a lot of things beyond just digital money. The same methodology will be essential for things like secure confirmed transactions between entities far distant from each other (like space stations, moon colonies, etc. - this happens to be one of my interests); it will be used for 'digital contracts' with its internal scripting system, and perhaps even for guaranteed unique digital identity; and it has the powerful feature that it doesn't depend on any external agency - governments or whatever. So bitcoin itself is having growing pains, and it may or may not survive and grow, but don't believe that the methodology won't be an essential part of many future activities.
That doesn't work. You don't have orbital velocity at that elevation. You essentially have 0 velocity relative to the Earth, until gravity starts to pull you down. So you'd still have to have some large amount of thrust to get you moving at 7-9km/s horizontally. Now you _could_ go to say, 2x LEO and start falling while you accelerate. But that's still a lot of fuel etc.
I'll just note that the X-window system was designed and built for systems much more powerful than the ones it was built on. The designers knew the capabilities would be available 'soon'. That's not a great example but indicative. Doing thought experiments of this kind is not stupid, just hopeful. Leonardo Da Vinci designed a simple airplane that was proved to be workable in the last decade or two. Da Vinci couldn't have built it because there were no motors to drive it at that time.
This provides a perfect excuse for an experiment / prank I've always wanted to do - hang a roll of toilet paper out of a plane and let it spin out and fall. Today's version would be to take a balloon to the top of the atmosphere and drop a ribbon to the ground, then let the top go. Make it out of something fish can eat, and do it over the ocean, so it doesn't pollute too much and you don't have to worry overmuch about wrapping it around someone's house 50 miles away.
Slashdot Mirror
Just call it Poop, since it is found outside Uranus. :P
One of the articles I read today says that the Army has already got that going. They are already firing 'smart' projectiles from howitzers and other large guns, and I would think that the accelerations are equivalent.
Just idly thinking about this, solid state electronics can take a lot. When you drop your watch on a concrete floor it may experience 700 G deceleration on impact, at an arbitrary angle.
But it's a function of time. Since the projectile traverses the distance in, e.g., 1/5 the time, the gravitational drop (I forget the real term) will only be 1/5 as much.
I've seen numbers up to 200 miles, vs. typically 30-40 miles for conventional rounds.
There's some video of one of these penetrating a 12 inch thick armor plate. IIRC it was still supersonic coming out the back side.
I'll add that I just read that 155mm rounds cost $50,000 each. So it's even cheaper than conventional artillery.
There are several advantages to railguns for the Navy, in lethality, cost-per-round, how much ammo you can carry, and overall safety.
Lethality - the kinetic energy of a 'passive' round at these velocities is equivalent to or greater than an explosive round (though I would think it might not be all that useful in all circumstances - just flying through some softer materials instead of blowing them up). As the videos show, the 'kill' factor is substantial. The projectiles are also much less affected by gravitational drop and windage - I would think proportional to the velocity - so accuracy will be better. The higher velocity also allows for firing at much longer range - up to 200 miles vs. 30 for the latest 155mm round.
Cost-per-round - while not as cheap as lasers (the laser about to go through sea trials has a cost of about $1 per shot), these systems should have a cost-per-round an order of magnitude cheaper than the big artillery presently in use. (I just read that 155mm shells cost $50,000 each.) It's much easier, cheaper, and safer to build a solid chunk of tungsten or whatever than a huge shell, especially when the savings in transport and necessary safety systems and procedures is taken into account.
How much - the propellant takes up a lot of space, must be stored in special containment that takes up more space. All of that space can be used to store actual projectiles instead, possibly multiplying the number of rounds available by a factor of 5 to 10. Add to that the the higher kinetic energy allows a smaller projectile to be equally effective, which means you can increase the number even more.
Safety - this eliminates the problem of ammunition exploding either in the ship that will use it, or the supply ship. There are many instances of a single 'lucky' hit on a ship that happens to penetrate the ammunition magazines, whereupon that explosion rips the ship in half. The explosives used in ammunition are also toxic. Removing the propellant greatly increases the survival probability in the event of a hit, and eliminates the probability of an unfortunate accident sinking the ship. This also means the supply ships are safer and can deliver much more ammunition in one trip.
It is _possible_ to land reasonably safely in the ocean. It requires a lot of skill and luck. Basically the plan has to orient in the same direction as the swells, slow down to just above stall speed (still about 150 knots IIRC), take a nose high attitude to prevent cartwheeling, and basically 'land' as slowly as possible, preferably picking the moment of contact on a wave peak. This of course works much better when the water is flat, which it rarely is in the southern Indian Ocean and the Southern Ocean - read up on the "Roaring Forties". Even once you have 'landed', the high waves have enough force to start stressing the plane to the breaking point, and as soon as the doors open the waves are going to play hell with rafts and people trying to get out on them. It's not quite like boarding a raft in a hurricane, but it's close.
Especially in the Southern Ocean. That is not flat water.
There was a sci fi story that went like that - but I think it was people from the future, who needed the bodies for some reason. So just before everyone died they pulled the real bodies and substituted fake 'meat' bodies that, after the plane burned etc., would be easily assumed to be real.
A friend of mine used to work for a company that built satellite receiving antennas, working on the software for the mounts. One of the things they would do is peruse the published satellite ephemera - I think each satellite's data was 80 points - and look for places where no satellites officially existed. Then they'd point their antenna there, and bingo! They found several military satellites that way.
So THAT's what happened. Your minions hijacked the plane and flew it to your secret submarine airbase, which rises to the surface when needed!
A British airliner that disappeared a few miles from the airport back in 1951 was recently discovered. Its next-to-last messages (via Morse Code) were that it was close to landing. Its fate was unknown until 1998. And that was on land. The area to be searched, given the best possible scenario with present data, is IIRC 22,000 square miles, about the size of Rhode Island, Massachusetts, Connecticut, and New Hampshire combined - about 1/3 of New England or about the same as Latvia or Lithuania, or 2/3 of Scotland. This is a much harder problem than the Air France jet of a few years ago, where they knew within a small range where the plane was likely to be.
I don't think it's possible for the pilot to shut off the flight recorders, at least without climbing all over the airplane. They are independently powered and situated at the back of the plane. They may only be accessible from outside the plane - I don't know this for sure.
To add to that, that area of ocean has about the worst conditions for ships, planes or helos. The "Roaring Forties" is not named that for nothing. A typical 'nice' day there will have 30 to 60 knot winds and 20 foot seas, plus a lot of fog, clouds and rain, air temps in the 0C to 10C range, and sea temps of 0C. Of course, if that's too balmy, there's always the Furious Fifties and Screaming Sixties. The Indian Ocean gradually becomes the Southern Ocean, which is the only ocean that has no barriers to its west-to-east current to slow it down, and the air above it is the same. The speeds are also multiplied because this is the air current that is balancing the east-to-west flow at the Equator, and also the rising air over the Equator sinks back down around the 30th parallel. But the circumeferential of the Earth at that latitude is about 1/2 that at the Equator, so the air travels twice as fast.
Think of Jupiter, and the tremendous winds generated there and the different bands going different ways - if there were no land masses the winds on Earth would look similar.
Then there's the depth and underwater terrain - the depth ranges from 3000 to 23000 feet (Mt. Everest is 29000) and is reportedly very rugged with canyons etc. It's one of the least explored parts of the global ocean, because of the conditions.
Most of the electronics in the cockpit - radios especially - are decades-old technology. This is in part because of the overlapping and 'rigorous' FAA and FCC standards. If a single component - a resistor, whatever - is changed, the entire unit has to go through certification all over again, by both agencies. This costs perhaps $10 million, and the total sales of that model radio may be 10,000 units, which means the amortized cost of certification is on the order of $1000 per radio. That is direct cost in advance of manufacturing. Back when I was flying, CB radios that cost under $100 had better reception and better voice quality than $3000 aircraft radios.
You're such a sentimentalist. :)
I haven't kept up, but it sez here::
It is widely stated that Quartz "uses PDF" internally (notably by Apple in Quartz's early developer documentation[5]), often by people making comparisons with the Display PostScript technology used in NeXTSTEP and OPENSTEP (of which Mac OS X is a descendant). Quartz's internal imaging model correlates well with the PDF object graph, making it easy to output PDF to multiple devices.[6]
WRT to OSX, there is history. Back in the days of NeXT, Jobs & co. decided to use Display Postscript for a variety of reasons. A few of the reasons: X back then was huge, ungainly and a total beast to work with using the limited memory and cycles available (The NeXTstation used a 25MHz 68000); their team were not ever going to be able to morph X into an object-oriented platform, which NeXT definitely was; Display Postscript was Adobe's new Hotness; the NeXT folks could write drivers for DP that worked with the Texas Instruments signal processor (TM-9900? I forget), which was truly amazingly fast at screen manipulation; and the X architecture didn't fit well with either Display Postscript or the TM-9900.
In 2001 I had a NeXTstation that I added some memory and a bigger disk to. The machine was by then more than 10 years old. For normal workstation duties, it was faster than my brand new desktop machine due entirely to the display architecture. But compiling almost anything on that 25MHz CPU was an overnight task - I had one compile that ran three days.
... has been going on for almost as long as coinage itself. One of the advantages of paper money (in addition to weight, lower manufacturing cost, etc.) is that it can be harder to forge. Any shmuck with a press can create coins that are hard to distinguish from the real thing. On a larger scale, one of the big problems today with gold is people hollowing out gold bars and filling them with tungsten, or starting with tungsten and wrapping a small amount of gold. These are indistinguishable from the real thing, for the non-expert and even for experts without the necessary equipment (and suspicion).
IANA bitcoin holder, but having looked into the original Nakamoto paper (which is short and much better than any of the derivatives), and discussed this with people who know, the bitcoin methodology or protocol or whatever is with us to stay, and will be used for a lot of things beyond just digital money. The same methodology will be essential for things like secure confirmed transactions between entities far distant from each other (like space stations, moon colonies, etc. - this happens to be one of my interests); it will be used for 'digital contracts' with its internal scripting system, and perhaps even for guaranteed unique digital identity; and it has the powerful feature that it doesn't depend on any external agency - governments or whatever. So bitcoin itself is having growing pains, and it may or may not survive and grow, but don't believe that the methodology won't be an essential part of many future activities.
Amusing - according to Wikipedia, egg albumin is used as a binder. Oops, not so vegan after all!
Hence butts.
Yes, metals are bad. Water (source of hydrogen = protons) is the best shield, or so say Those Who Know Such Things.
That doesn't work. You don't have orbital velocity at that elevation. You essentially have 0 velocity relative to the Earth, until gravity starts to pull you down. So you'd still have to have some large amount of thrust to get you moving at 7-9km/s horizontally. Now you _could_ go to say, 2x LEO and start falling while you accelerate. But that's still a lot of fuel etc.
I'll just note that the X-window system was designed and built for systems much more powerful than the ones it was built on. The designers knew the capabilities would be available 'soon'. That's not a great example but indicative. Doing thought experiments of this kind is not stupid, just hopeful. Leonardo Da Vinci designed a simple airplane that was proved to be workable in the last decade or two. Da Vinci couldn't have built it because there were no motors to drive it at that time.
This provides a perfect excuse for an experiment / prank I've always wanted to do - hang a roll of toilet paper out of a plane and let it spin out and fall. Today's version would be to take a balloon to the top of the atmosphere and drop a ribbon to the ground, then let the top go. Make it out of something fish can eat, and do it over the ocean, so it doesn't pollute too much and you don't have to worry overmuch about wrapping it around someone's house 50 miles away.