Just rig up a switch that will dump a couple capacitors into the recorder. Those used in really crazy stereo installations should work.
Obeying the law and get hit--cool, the recorder will show that. Driving at the speed of stupid and plow through a bus stop--flip the switch so there's a bit less evidence.
In all seriousness, though, it looks like things worked how they're supposed to this time--the guy got caught being criminally stupid, and is paying the price. Like above posters pointed out, though, the data could be misconstrued. Wheels spinning on a loose surface might look like you're going 100 mph.
I don't think these things are complicated enough to employ any kind of inertial rate sensors--accelerometers and gyros could tell you precisely what the vehicle was doing in three dimensions, but at great cost.
In the meantime, just keep that capacitor charged:)
People tend to blow this out of proportion. Lets say all these satellites are the size of a small economy car. Put 2000 Beetles on the surface of the earth. Not very close together, eh?
Okay, granted--a lot of those will want to congregate around the equator. But push them all out a few hundred miles. Factor in the fact that all satellites at a given orbit are going the exact same speed--Kepler's Laws and all.
Sure, it's an issue. The elliptical orbits cross the plane of the LEO and GEO orbits, and the body is going faster the closer to earth. I'd hate to see a guy floating around the ISS get hit by a Red bolt going 9km/sec.
But it's not some dense floating junkyard up there.
Yes, and GLONASS sucks. Maybe even 'sucked'--I'm not sure it's still operational in any useful capacity. As I recall (I'm going from memory here), the GLONASS constellation was optimized for high latitudes--probably a Molniya orbit, or something similar. Anyway, it's more work than just putting them in a half-sync orbit like the NAVSTAR constellation for GPS.
I know a guy that was with Space Command, working GPS since the early days. He met some Soviet Major (or something) at a conference once, years later. The guy related that his tank had both a GPS and a GLONASS reciever installed. His description of each?
"GPS--very very good. GLONASS--dogshit."
My biggest problems with GALILEO?
First, the levels of precision--the stuff they're givng their police and EMS are on par with what our military has under lock and key. Which sounds harder to steal? (This may not be an issue now--been a long time since I read that.)
Second (and more importantly), it's going to be expensive. As soon as the system is working, the EU is going to require anyone that wants to use GNSS for navigation to use GALILEO instead of GPS. Some requirement about 'safety' or somesuch. And they'll tax all the receivers. And charge for each approach (I'm told they charge you for about all they can in the European airspace system--approaches, wx reports...).
Just wait. I guarantee you it will happen. Anyone flying over Europe will have to buy a GALILEO receiver. I'd bet Collins and Trimble are already lining up dual-system receivers.
If it were that easy, you wouldn't hear mechanics and the producers of diagnostic machines/software complaining.
But it is that easy. I have the FSM for my truck. The same one the dealer techs use. Bought it straight from the manufacturer.
Granted, Chrysler is better in this respect than some others. Solution?
Don't buy a car from a manufacturer that tries to lock you in to their service department. It won't change anything in the long run (most people don't even know about this issue, after all), but it will save you some money.
My truck isn't ancient (it's a '99), and it's full of computers, but there's nothing on there I'd take it to the dealer for. A good mechanic or I can fix anything that breaks on the engine--probably better than the 'tech' at the stealer.
It's a 99 Dodge Ram (turbodiesel). I have the Haynes manual, and I'm pretty sure there's a code table in there. Honestly, I can't remember now--I also paid $90 for the factory service manual, and I _know_ it has the codes--it's what the techs at the dealer use, after all.
Besides, it's an OBD-II interface. While some of these are manufacturer-specific, I haven't had trouble finding the codes--here, for example.
Not always good enough to tell you exactly what to fix (P0216--injector pump timing fail isn't the most intuitive way to say your $2000 injection pump is shot), but the FSM really helps here.
What makes you think the dealer techs know anything about fixing your car? Many are lost if the computer doesn't tell them exactly what to fix. Chrysler, Honda, Toyota, Chevrolet--I've tried them all. A couple had a decent tech or two. Most would resort to parts changing in an effort to make the problem go away.
If a small repair shop can stay in business against a mega-dealer, odds are they may know what they're doing. Not always, but a 'five-star' or 'super-mega-best-service' award from corporate doesn't mean jack, either.
When manufacturers are cutting the underhood light to save money (I guess it adds up over a few 100,000 vehicles), putting in a display large enough to be useable is not something they want to do. And instruments have been getting more simplistic over the years because that's how consumers want it . Women in particular (not being sexist here--actual survey results) are made uneasy by a large bank of controls. How many vehicles these days have only a speedometer, fuel gauge, an oil pressure light, coolant temp light, and a check engine light? Me, I added gauges (fuel pressure, because the factory pump is weak, and it's a $4000 job to replace the injection pump when it burns up; and no diesel truck should be without EGT and boost). I'd be happy if it looked like an airplane cockpit, but the common consumer says it's overwhelming, so they go simple.
Even translating into English, most people wouldn't want this display. After all, a message that pops up saying something like FAULT--P0216: INJECTION PUMP TIMING FAILURE is not going to be intuitive to most, and sounds scary. Plus, you need more room on the EEPROM to store a code table--numerical codes are much more efficient.
If your really want to know what code is latched, pay $50 and buy a code scanner and look it up in the $10 Haynes manual.
I agree! It used to be that the average mom & pop or even home enthusiast could purchase the "decoding" machines or the books that translated the engine light codes. Those days ended around 1992, I believe.
Not so--many cars still have this feature. My truck, for example--turn the key on-off-on-off-on within 8 seconds, read the codes off the odometer display. Look up those codes in a $10 Haynes manual. Can't find one of those? Buy the manual from the factory. More expensive, but should be under $100, and will tell you how to fix everything else on your car, too.
Go to Autozone. Request codes scanned (free, most places). Write down code. Buy Haynes/Chilton service manual ($10). Look up code in table. Replace offending part/troubleshoot offending system per table.
Even a factory service manual (mine was $90 and is thick as a few phone books) and a code scanner ($70--$200, or make your own--OBD-II is a simple protocol, mostly) won't set you back that much, and are handy to have anyway.
Like the other posters, I'm leery of this air-water intercooler. I was about to denounce the poster of confusing his radiator with an intercooler, but I suppose there could be a factory-equipped air-water intercooled vehicle out there. Don't know what it would be, but it's possible...
Good advice. There may be better, however. Many vehicles, especially those with a cult following (VW, many flavors of 4x4s and large trucks) have user groups on the internet. The TDR has saved me plenty of money on my Ram. Common problems, sources for parts, sneaky dealer tricks--all there. And the ability to ask a question, and get an answer within an hour from a dozen guys that have been there before is well worth the $35/yr I pay (the quarterly magazine is nice, too). Even without the $35, people can peruse the forums if they're cheap.
Also, as an above poster noted, Autozone will scan your codes for free. The teenagers behind the counter usually won't know what it means or how to fix it, but you can take that code, Google for it, consult your friendly local user's group for it, or read it straight from the factory service manual--I paid $90 for mine, straight from Chrysler, and it's the same one the techs use.
Maybe there are car companies that intentionally obfuscate this stuff, but I've never had a vehicle throw a code and not be able to figure out what it meant.
911 isn't very useful in true emergency situations if your location can't even be traced. If you're being burglared (sp?), you don't have time to tell them your address. You call 911, say, "There's a burglar in my home, HELP!", and run and hide. You don't wanna be caught by the burglar on the phone trying to give them directions to your house.
Actually, that can be a dangerous thing to do. The ANI/ALI system in an E-911 center will bring up your phone number, name, and address on the screen if you call, and even show where you are on a map, complete with little icons for the nearest fire hydrants, little police cars, ambulances, and fire trucks driving around (I've seen it a few times--it's pretty neat). But it doesn't do all this magically--it gets all its records from the phone company. Anyone ever had a billing problem with the phone company?
There have been several incidents in my old County where the info pulled up was not correct--either it reflected the previous person to have that number, or a minor typographical error (Johnson Road instead of Johnson Street can be problematic when they're twelve miles apart).
This is why they'll always ask you for your address when you call--they're making sure. And don't just say, "Yeah, sure, just send me the damn ambulance!" when they ask/try to confirm--if the ambulance goes the wrong way, Grandma might not survive her heart attack (ask me how I know).
So getting back to the parent poster, if you're pressed for time, tell them your address first, then the problem if you have time. If you don't, they'll figure out you're in trouble anyway, and know for sure where to send the cops.
Despite such technical hurdles, space-based arms are legal. The Outer Space Treaty of 1967 only bans nuclear weapons and other weapons of mass destruction from orbit.
There's a good reason for that, too. Read up on Starfish Prime. Dealt with upper-atmospheric testing early in the US nuclear weapons program. Bad scifi in movies has made us all aware of the EMP effect, and this is where they figured it out over 50 years ago.
Basically, any low-orbit nuclear detonation throws out a strong electromagnetic pulse. This knocks out other satellites, communications systems, power grids... It did some damage way back then, and they didn't have near the communications infrastructure. It would be madness today, at least for an industrialized nation--it hurts you just as bad as the other guy.
Also managed to super-energize the Van Allen belts for a while--some said a decade or two.
Hypergolic fuels are rocket fuels that ignite spontaneously when mixed. The most commonly used combination (IIRC) is hydrazine (which is H2NNH2) and (I believe) inhibited red fuming nitric acid.
They're handy for manuvering thrusters and smaller rocket motors (liquid hydrogen/oxygen still being the choice for liquid-fueled heavy-lifters), because you don't need any kind of igniter--just squirt some of each in the combustion chamber, and it ignites on its own.
This aloud a jet of hot gas from the burning booster rocket to escape. THAT caused the large tank to explode.
Actually, I believe the jet of escaping gas impinged on the lower explosive bolt assembly where the SRB is connected to the ET. When this failed, the SRB pivoted on the upper mount assembly, leading to loss of structural integrity of the tank and subsequent loss of the vehicle.
What? Fuel? Who says you need to use liquid fuels? Try solids that can be lit and relit in space. The fuel cores could be sent on shuttles without as much worry about volatility than liquids. There is one way to stop a burn in space--stop the oxidizer (you're in vacuum, figure it out).
Hmm. I'm not sure it's that easy. I'm pretty sure that solid-fuel rockets have the oxidizer mixed in with the fuel and are fully self contained. The SRBs on the Shuttle, for instance, have nothing pumping an oxidizer in.
There are (in my experiences) two types of propulsion engineers--those who love solid fuels, and those who hate them.
On the positive side, it keeps you from messing with those nasty hypergolic fuels like hydrazine.
On the negative side, once you light it, there's no easy way to stop it until it's out of fuel--it's like a big highway flare. IIRC, if the shuttle needs to abort early in the launch sequence, the only thing to do is to jettison the SRBs and let them go flying merrily on their way (to be destroyed later by range safety).
Liquid fuels can be throttled or shut off. A solid booster's thrust can only be controlled by how the fuel is poured in the casing (star patterns and whatnot give high initial thrust, then back off), and not easily shut down.
One interesting insight: after the Challenger explosion it became obvious that we would never refuel a rocket with volatile fuel at a space station because the threat to the station would be so great.
Everyone who saw Challenger's loss--remember what it looked like? Try here if not. No huge fireball (for the size of the vehicle, anyway) like you'd expect from truly 'volatile' fuels. There was a good amount of fire, but I believe most of the fuels were converted to steam. Even the fuel in the solid rocket boosters (ammonium perchlorate and aluminum) isn't what I'd call 'volatile'--it's designed to burn steadily. The hydrazine used for the OMS engines (and RCS thrusters, IIRC) is another issue--hypergolic fuels are quite dangerous (remember those old WWII videos of German V-2 rockets falling over and exploding?), but there's not all that much of them.
At any rate, the cause of Challenger's loss was the destruction of the external tank's structural integrity, which allowed the liquid hydrogen (and oxygen) to escape and ignite. I'm relatively certain the ISS already has LOX and liquid H2 tanks for the fuel cells (unless all power comes from the solar panels) and oxygen/water generation. What's the issue?
Granted, if we're talking about the shuttle, it doesn't use its main engines after orbit insertion (as the fuel tank is jettisoned), so all it's got is the OMS engines, and like I said--hydrazine is nasty shit. I can understand not wanting a bunch of it stored on the station. Linking that to Challenger doesn't make sense, though--it wasn't hydrazine that killed them.
Of course, they could park a few tanks a safe distance away if they could keep them in the same orbit. Maybe at the L1 point that would work, but we're into a whole new argument there...
Any signal can be jammed. Remember the flap when it was found out that Russian GPS jammers had been sold to Iraq?
Yeah, and as I recall, they took them out with JDAMs. Which are (partially) GPS guided. I think someone was trying to make a point, there.
You can jam anything, given enough power. If I'm on batteries, and you're on the grid, you can ruin my whole day. Fortunately for the jammee (but not the jammer), these are easy to locate, especially the wideband ones. Imagine a searchlight--sure, a 3-million candlepower light can blind you from a few hundred yards, but you can see it from a helluva lot further away than that. Hell, a Boy Scout could probably DF one with $10 in Radio Shack parts.
The Air Force has another name for jammers. Targets.
Like the parent said--encryption is the key. If they can't use it, there's no need to jam it. I'm not that current on Galileo, but as I recall one of the main sticking points was it offered it's high-accuracy signal (equivalent to the NAVSTAR GPS' P(Y) code) to just about anyone.
GPS with WAAS gets you to, say, 1m RPE, 2-sigma. Who really needs more than a 1-meter accuracy in the civilian world? Surveyors already do post-processing and get millimeter-level accuracy.
The only real use for Galileo is to make money for the EU. Just put the system up, and say anyone that flies in their airspace must have an approved Galileo receiver--GPS isn't good enough. Each receiver will have a tax on it that goes to the governments coffers. Want to utilize the system to fly a flight plan? That's another fee.
Don't believe me? From what I understand of the European aviation system, that's how it will go. Flight plans, weather reports, runway usage--you already get billed for that, now GNSS will make money, too. Why do you think everyone comes to the US to get a pilot's license?
Galileo's only benefit over NAVSTAR is that the EU can make money off of it. I'll take my WAAS-enabled C/A code reciever for $150, thanks.
The reason you can't hear sound in space is because it's almost a vacuum. Back around the time of the Big Bang, matter was packed much closer together and density was far higher. Much higher, for example, than the density of the Earth's atmosphere. So yes, sound vibrations could propagate around in the early universe.
All you people who keep complaining that 'You couldn't really hear a TIE Fighter like that!', or 'The Death Star couldn't really make a shockwave like that--it's in a vacuum!'--this is why.
After all, it was, "A long time ago..."
--Ribald
Re:Space debris, Star wars and the Kessler Effect
on
Next Major War in Space?
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· Score: 2, Interesting
Forgive me if the question is a little ignorantly phrased, but what about the same orbit, but going the opposite direction?
Yeah, that could work, but there are problems with that, too.
One problem is getting it going in the opposite direction--you've got the earth rate to contend with. These velocities are not related to a point on the surface of the earth--they're velocities in an intertial frame. In general terms, you have to be going 8km/sec with respect to a point at the very center of the earth. To get going backwards, you have to first 'slow down' from the initial velocity of the spinning earth's surface, then accelerate to circular satellite speed in the opposite direction.
I suppose this is do-able, it just takes a lot more fuel. But even if you do that, closing speed is going to be about 16 km/sec. with your target. That's about 36000 miles per hour. Guidance becomes a real issue at those speeds--there's not much time to correct, and satellites are small.
Even an orbital rendezvous is difficult, as they found with Apollo VIII (I think). To end up in the same place in the same orbit, starting in the same orbit, the trailing capsule had to actually slow down, dropping to a lower orbit, speed back up to circular satellite speed, catch up with the lead capsule, accelerate to gain altitude, then slow back down to circular satellite speed for that orbit. Hitting something with any speed is more difficult. Even coming at it head on...I'm just not sure how easy it can be done. The USAF had an ASAT program back in the 80s that was launched from a fighter, but to my knowledge, we're the only country with guidance systems able to make the rendezvous, and even that had and explosive warhead, as I recall, obviating the need for a direct hit.
It's just not as simple as all those space movies have led us to believe.
Not very fast, no, but they do decay. Gravitational effects of the sun and moon also disturb orbits.
Not very quickly, mind you, but there is a lot of space way out there.
"No actual space war even has to be fought," Primack said. "Any country that felt threatened by America's starting to place lasers or other weapons in space would only have to launch the equivalent of gravel to destroy the sophisticated weaponry."
True in theory, but the application is a bit harder.
It's actually getting the 'gravel' to hit the satellites. Needs a pretty good guidance system to hit something the size of a few basketballs (though large solar arrays make it a bit easier), especially when it's moving at 8000 m/s. Not many people have inertial guidance systems this good (I work for a company that does make them)--I believe all that do are our allies. GPS gets tricky the higher you go, and doesn't really have that accuracy level, anyway, especially if you don't have the crypto to get the Y-code PPS signal.
"So we just put a big gravel cloud in front of the satellite, and it will tear itself apart!", you may say. Only problem here is, if you put it in the same orbit, it has to be going the same speed. Faster, it goes into a higher (elliptical) orbit. Slower, it goes into a lower (also elliptical) orbit, and likely burns up in the atmosphere.
Orbital mechanics is all pretty straightforward, and the math hasn't changed much in a couple hundred years. It's just not the same as shooting an airplane down with a missile. The intercept velocities are much, much higher, maneuvering on-orbit is a slow process, and you don't have the aerodynamic forces of lift and drag to help you out.
Many Intelligence satellites are in a low altitude (150-300 mile) polar orbit. Reading newspapers from 22,000 miles (geosync) just can't be done yet.
Not to mention the fact that a GEO bird would always be looking at the same thing. Put it in LEO, and it'll eventually be over what you want to look at.
You don't want to be burning the hydrazine all the time moving an intel sat around. They don't carry much (launch weight restrictions), and once it's gone, you can't even do attitude corrections anymore.
Junk deorbits rapidly. The square-cubed law means that they have higher surface area for their weight, and therefore proportionately higher atmospheric drag. Massive amounts of junk pumped into low orbits would be gone in months. In very high orbits (like geosync, not sure about the GPS orbits) it's a different situation, but there's also a lot more space at that distance.
Very likely true. People seem to have a great misconception about 'space junk' running into important stuff. What most people don't realize is that in any given orbit, all satellites are moving at the exact same speed. They have to--it's basic physics and orbital mechanics. Pick up a copy of Bate, Mueller, and White if you don't believe me.
If it's in LEO (low earth orbit), in a circular orbit, it's going roughly 8 km/sec. Slow it down, it drops to a lower orbit, drag increases, it falls lower, and burns up. Speed it up, it goes into an elliptical orbit. Granted, this elliptical orbit may intersect with the orbit of another object, and theoretically collide, but there's a lot of room in space, and a bolt flying around has to get pretty lucky to nail a satellite. In all likelihood, this new elliptical orbit will intersect with the atmosphere at some point, start slowing down, and eventually spiral in.
The GEO birds are a lot farther out--6.5 Earth radii, as I recall (GPS is roughly half-sync, BTW, so figure half that). As the previous poster said, there's a lot more room out there.
At any rate, when stuff blows up in space, the debris cloud generally stays in the same orbit as the original satellite, and spreads gradually. 8km/sec is the driving variable here. Sure, if two satellites collede at obtuse angles (not very likely) (or one gets hit with a missile coming from the opposite direction), the debris is going to spread out. Some small bit will probably end up in a circular orbit (if it's a GEO bird, but I don't think missiles will reach that far), most will decay into the atmosphere, and some might go into HEO (higly-elliptical orbit). Get it going faster than 11.2 km/sec, and it's gone for good.
We're not going to have a cloud of debris constantly orbiting our planet after some kind of space war. I can't see how any appreciable amount of it would end up in a stable circular orbit, much less a low orbit--anything that gets accelerated in a collision/explosion will need a second acceleration to stabilize into a circular orbit at another altitude. The elliptical stuff will almost certainly all run afoul of the atmosphere.
Sure, some bigger chunks might manage to smash into our homes, but we're not going to be trapped for millennia...
Satellite seeking missiles aren't the easiest (or cheapest) weapons to build. As far as I know, the USAF is the only organization to ever construct one, namely the ALMV.
A very large missile launched from an F-15 in a ballistic climb, the project was canceled due to cost. I believe they did test some of these, and might even have some in a bunker somewhere, but I can't find a source on that.
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Just rig up a switch that will dump a couple capacitors into the recorder. Those used in really crazy stereo installations should work.
:)
Obeying the law and get hit--cool, the recorder will show that.
Driving at the speed of stupid and plow through a bus stop--flip the switch so there's a bit less evidence.
In all seriousness, though, it looks like things worked how they're supposed to this time--the guy got caught being criminally stupid, and is paying the price. Like above posters pointed out, though, the data could be misconstrued. Wheels spinning on a loose surface might look like you're going 100 mph.
I don't think these things are complicated enough to employ any kind of inertial rate sensors--accelerometers and gyros could tell you precisely what the vehicle was doing in three dimensions, but at great cost.
In the meantime, just keep that capacitor charged
--Ribald
People tend to blow this out of proportion. Lets say all these satellites are the size of a small economy car. Put 2000 Beetles on the surface of the earth. Not very close together, eh?
Okay, granted--a lot of those will want to congregate around the equator. But push them all out a few hundred miles. Factor in the fact that all satellites at a given orbit are going the exact same speed--Kepler's Laws and all.
Sure, it's an issue. The elliptical orbits cross the plane of the LEO and GEO orbits, and the body is going faster the closer to earth. I'd hate to see a guy floating around the ISS get hit by a Red bolt going 9km/sec.
But it's not some dense floating junkyard up there.
--Ribald
Yes, and GLONASS sucks. Maybe even 'sucked'--I'm not sure it's still operational in any useful capacity. As I recall (I'm going from memory here), the GLONASS constellation was optimized for high latitudes--probably a Molniya orbit, or something similar. Anyway, it's more work than just putting them in a half-sync orbit like the NAVSTAR constellation for GPS.
I know a guy that was with Space Command, working GPS since the early days. He met some Soviet Major (or something) at a conference once, years later. The guy related that his tank had both a GPS and a GLONASS reciever installed. His description of each?
"GPS--very very good. GLONASS--dogshit."
My biggest problems with GALILEO?
First, the levels of precision--the stuff they're givng their police and EMS are on par with what our military has under lock and key. Which sounds harder to steal? (This may not be an issue now--been a long time since I read that.)
Second (and more importantly), it's going to be expensive. As soon as the system is working, the EU is going to require anyone that wants to use GNSS for navigation to use GALILEO instead of GPS. Some requirement about 'safety' or somesuch. And they'll tax all the receivers. And charge for each approach (I'm told they charge you for about all they can in the European airspace system--approaches, wx reports...).
Just wait. I guarantee you it will happen. Anyone flying over Europe will have to buy a GALILEO receiver. I'd bet Collins and Trimble are already lining up dual-system receivers.
--Ribald
If it were that easy, you wouldn't hear mechanics and the producers of diagnostic machines/software complaining.
But it is that easy. I have the FSM for my truck. The same one the dealer techs use. Bought it straight from the manufacturer.
Granted, Chrysler is better in this respect than some others. Solution?
Don't buy a car from a manufacturer that tries to lock you in to their service department. It won't change anything in the long run (most people don't even know about this issue, after all), but it will save you some money.
My truck isn't ancient (it's a '99), and it's full of computers, but there's nothing on there I'd take it to the dealer for. A good mechanic or I can fix anything that breaks on the engine--probably better than the 'tech' at the stealer.
--Ribald
It's a 99 Dodge Ram (turbodiesel). I have the Haynes manual, and I'm pretty sure there's a code table in there. Honestly, I can't remember now--I also paid $90 for the factory service manual, and I _know_ it has the codes--it's what the techs at the dealer use, after all.
Besides, it's an OBD-II interface. While some of these are manufacturer-specific, I haven't had trouble finding the codes--here, for example.
Not always good enough to tell you exactly what to fix (P0216--injector pump timing fail isn't the most intuitive way to say your $2000 injection pump is shot), but the FSM really helps here.
--Ribald
What makes you think the dealer techs know anything about fixing your car? Many are lost if the computer doesn't tell them exactly what to fix. Chrysler, Honda, Toyota, Chevrolet--I've tried them all. A couple had a decent tech or two. Most would resort to parts changing in an effort to make the problem go away.
If a small repair shop can stay in business against a mega-dealer, odds are they may know what they're doing. Not always, but a 'five-star' or 'super-mega-best-service' award from corporate doesn't mean jack, either.
--Ribald
When manufacturers are cutting the underhood light to save money (I guess it adds up over a few 100,000 vehicles), putting in a display large enough to be useable is not something they want to do. And instruments have been getting more simplistic over the years because that's how consumers want it . Women in particular (not being sexist here--actual survey results) are made uneasy by a large bank of controls. How many vehicles these days have only a speedometer, fuel gauge, an oil pressure light, coolant temp light, and a check engine light? Me, I added gauges (fuel pressure, because the factory pump is weak, and it's a $4000 job to replace the injection pump when it burns up; and no diesel truck should be without EGT and boost). I'd be happy if it looked like an airplane cockpit, but the common consumer says it's overwhelming, so they go simple.
Even translating into English, most people wouldn't want this display. After all, a message that pops up saying something like FAULT--P0216: INJECTION PUMP TIMING FAILURE is not going to be intuitive to most, and sounds scary. Plus, you need more room on the EEPROM to store a code table--numerical codes are much more efficient.
If your really want to know what code is latched, pay $50 and buy a code scanner and look it up in the $10 Haynes manual.
--Ribald
I agree! It used to be that the average mom & pop or even home enthusiast could purchase the "decoding" machines or the books that translated the engine light codes. Those days ended around 1992, I believe.
Not so--many cars still have this feature. My truck, for example--turn the key on-off-on-off-on within 8 seconds, read the codes off the odometer display. Look up those codes in a $10 Haynes manual. Can't find one of those? Buy the manual from the factory. More expensive, but should be under $100, and will tell you how to fix everything else on your car, too.
--Ribald
Buy the factory service manual. It's the same thing the techs use at the dealer, so it better have them all. $90 isn't unreasonable.
--Ribald
Solution:
Go to Autozone.
Request codes scanned (free, most places).
Write down code.
Buy Haynes/Chilton service manual ($10).
Look up code in table.
Replace offending part/troubleshoot offending system per table.
Even a factory service manual (mine was $90 and is thick as a few phone books) and a code scanner ($70--$200, or make your own--OBD-II is a simple protocol, mostly) won't set you back that much, and are handy to have anyway.
Like the other posters, I'm leery of this air-water intercooler. I was about to denounce the poster of confusing his radiator with an intercooler, but I suppose there could be a factory-equipped air-water intercooled vehicle out there. Don't know what it would be, but it's possible...
--Ribald
That is why having the operational codes are important, to identify the problem and clear the flag.
Many of these codes will extinguish after so many cycles with no fault recorded. If the part's still broken, the code will just re-set, anyway.
And I believe the $100 code scanner you can buy from Autozone will clear codes, too. OBD-II is an industry standard, after all...
--Ribald
Best place to find car info - groups.google.com.
Good advice. There may be better, however. Many vehicles, especially those with a cult following (VW, many flavors of 4x4s and large trucks) have user groups on the internet. The TDR has saved me plenty of money on my Ram. Common problems, sources for parts, sneaky dealer tricks--all there. And the ability to ask a question, and get an answer within an hour from a dozen guys that have been there before is well worth the $35/yr I pay (the quarterly magazine is nice, too). Even without the $35, people can peruse the forums if they're cheap.
Also, as an above poster noted, Autozone will scan your codes for free. The teenagers behind the counter usually won't know what it means or how to fix it, but you can take that code, Google for it, consult your friendly local user's group for it, or read it straight from the factory service manual--I paid $90 for mine, straight from Chrysler, and it's the same one the techs use.
Maybe there are car companies that intentionally obfuscate this stuff, but I've never had a vehicle throw a code and not be able to figure out what it meant.
--Ribald
911 isn't very useful in true emergency situations if your location can't even be traced. If you're being burglared (sp?), you don't have time to tell them your address. You call 911, say, "There's a burglar in my home, HELP!", and run and hide. You don't wanna be caught by the burglar on the phone trying to give them directions to your house.
Actually, that can be a dangerous thing to do.
The ANI/ALI system in an E-911 center will bring up your phone number, name, and address on the screen if you call, and even show where you are on a map, complete with little icons for the nearest fire hydrants, little police cars, ambulances, and fire trucks driving around (I've seen it a few times--it's pretty neat). But it doesn't do all this magically--it gets all its records from the phone company. Anyone ever had a billing problem with the phone company?
There have been several incidents in my old County where the info pulled up was not correct--either it reflected the previous person to have that number, or a minor typographical error (Johnson Road instead of Johnson Street can be problematic when they're twelve miles apart).
This is why they'll always ask you for your address when you call--they're making sure. And don't just say, "Yeah, sure, just send me the damn ambulance!" when they ask/try to confirm--if the ambulance goes the wrong way, Grandma might not survive her heart attack (ask me how I know).
So getting back to the parent poster, if you're pressed for time, tell them your address first, then the problem if you have time. If you don't, they'll figure out you're in trouble anyway, and know for sure where to send the cops.
--Ribald
Despite such technical hurdles, space-based arms are legal. The Outer Space Treaty of 1967 only bans nuclear weapons and other weapons of mass destruction from orbit.
There's a good reason for that, too. Read up on Starfish Prime. Dealt with upper-atmospheric testing early in the US nuclear weapons program. Bad scifi in movies has made us all aware of the EMP effect, and this is where they figured it out over 50 years ago.
Basically, any low-orbit nuclear detonation throws out a strong electromagnetic pulse. This knocks out other satellites, communications systems, power grids... It did some damage way back then, and they didn't have near the communications infrastructure. It would be madness today, at least for an industrialized nation--it hurts you just as bad as the other guy.
Also managed to super-energize the Van Allen belts for a while--some said a decade or two.
Hypergolic fuels are rocket fuels that ignite spontaneously when mixed. The most commonly used combination (IIRC) is hydrazine (which is H2NNH2) and (I believe) inhibited red fuming nitric acid.
They're handy for manuvering thrusters and smaller rocket motors (liquid hydrogen/oxygen still being the choice for liquid-fueled heavy-lifters), because you don't need any kind of igniter--just squirt some of each in the combustion chamber, and it ignites on its own.
This aloud a jet of hot gas from the burning booster rocket to escape. THAT caused the large tank to explode.
Actually, I believe the jet of escaping gas impinged on the lower explosive bolt assembly where the SRB is connected to the ET. When this failed, the SRB pivoted on the upper mount assembly, leading to loss of structural integrity of the tank and subsequent loss of the vehicle.
But you are correct--the ET was not at fault.
What? Fuel? Who says you need to use liquid fuels? Try solids that can be lit and relit in space. The fuel cores could be sent on shuttles without as much worry about volatility than liquids. There is one way to stop a burn in space--stop the oxidizer (you're in vacuum, figure it out).
Hmm. I'm not sure it's that easy. I'm pretty sure that solid-fuel rockets have the oxidizer mixed in with the fuel and are fully self contained. The SRBs on the Shuttle, for instance, have nothing pumping an oxidizer in.
There are (in my experiences) two types of propulsion engineers--those who love solid fuels, and those who hate them.
On the positive side, it keeps you from messing with those nasty hypergolic fuels like hydrazine.
On the negative side, once you light it, there's no easy way to stop it until it's out of fuel--it's like a big highway flare. IIRC, if the shuttle needs to abort early in the launch sequence, the only thing to do is to jettison the SRBs and let them go flying merrily on their way (to be destroyed later by range safety).
Liquid fuels can be throttled or shut off. A solid booster's thrust can only be controlled by how the fuel is poured in the casing (star patterns and whatnot give high initial thrust, then back off), and not easily shut down.
One interesting insight: after the Challenger explosion it became obvious that we would never refuel a rocket with volatile fuel at a space station because the threat to the station would be so great.
Volatile fuels like, say, liquid hydrogen and oxygen? Yeah, that's scary. Really 'volatile' stuff.
Everyone who saw Challenger's loss--remember what it looked like? Try here if not. No huge fireball (for the size of the vehicle, anyway) like you'd expect from truly 'volatile' fuels. There was a good amount of fire, but I believe most of the fuels were converted to steam. Even the fuel in the solid rocket boosters (ammonium perchlorate and aluminum) isn't what I'd call 'volatile'--it's designed to burn steadily. The hydrazine used for the OMS engines (and RCS thrusters, IIRC) is another issue--hypergolic fuels are quite dangerous (remember those old WWII videos of German V-2 rockets falling over and exploding?), but there's not all that much of them.
At any rate, the cause of Challenger's loss was the destruction of the external tank's structural integrity, which allowed the liquid hydrogen (and oxygen) to escape and ignite. I'm relatively certain the ISS already has LOX and liquid H2 tanks for the fuel cells (unless all power comes from the solar panels) and oxygen/water generation. What's the issue?
Granted, if we're talking about the shuttle, it doesn't use its main engines after orbit insertion (as the fuel tank is jettisoned), so all it's got is the OMS engines, and like I said--hydrazine is nasty shit. I can understand not wanting a bunch of it stored on the station. Linking that to Challenger doesn't make sense, though--it wasn't hydrazine that killed them.
Of course, they could park a few tanks a safe distance away if they could keep them in the same orbit. Maybe at the L1 point that would work, but we're into a whole new argument there...
--Ty
Any signal can be jammed. Remember the flap when it was found out that Russian GPS jammers had been sold to Iraq?
Yeah, and as I recall, they took them out with JDAMs. Which are (partially) GPS guided. I think someone was trying to make a point, there.
You can jam anything, given enough power. If I'm on batteries, and you're on the grid, you can ruin my whole day. Fortunately for the jammee (but not the jammer), these are easy to locate, especially the wideband ones. Imagine a searchlight--sure, a 3-million candlepower light can blind you from a few hundred yards, but you can see it from a helluva lot further away than that. Hell, a Boy Scout could probably DF one with $10 in Radio Shack parts.
The Air Force has another name for jammers. Targets.
Like the parent said--encryption is the key. If they can't use it, there's no need to jam it. I'm not that current on Galileo, but as I recall one of the main sticking points was it offered it's high-accuracy signal (equivalent to the NAVSTAR GPS' P(Y) code) to just about anyone.
GPS with WAAS gets you to, say, 1m RPE, 2-sigma. Who really needs more than a 1-meter accuracy in the civilian world? Surveyors already do post-processing and get millimeter-level accuracy.
The only real use for Galileo is to make money for the EU. Just put the system up, and say anyone that flies in their airspace must have an approved Galileo receiver--GPS isn't good enough. Each receiver will have a tax on it that goes to the governments coffers. Want to utilize the system to fly a flight plan? That's another fee.
Don't believe me?
From what I understand of the European aviation system, that's how it will go. Flight plans, weather reports, runway usage--you already get billed for that, now GNSS will make money, too. Why do you think everyone comes to the US to get a pilot's license?
Galileo's only benefit over NAVSTAR is that the EU can make money off of it. I'll take my WAAS-enabled C/A code reciever for $150, thanks.
--Ribald
The reason you can't hear sound in space is because it's almost a vacuum. Back around the time of the Big Bang, matter was packed much closer together and density was far higher. Much higher, for example, than the density of the Earth's atmosphere. So yes, sound vibrations could propagate around in the early universe.
All you people who keep complaining that 'You couldn't really hear a TIE Fighter like that!', or 'The Death Star couldn't really make a shockwave like that--it's in a vacuum!'--this is why.
After all, it was, "A long time ago..."
--Ribald
Forgive me if the question is a little ignorantly phrased, but what about the same orbit, but going the opposite direction?
Yeah, that could work, but there are problems with that, too.
One problem is getting it going in the opposite direction--you've got the earth rate to contend with. These velocities are not related to a point on the surface of the earth--they're velocities in an intertial frame. In general terms, you have to be going 8km/sec with respect to a point at the very center of the earth. To get going backwards, you have to first 'slow down' from the initial velocity of the spinning earth's surface, then accelerate to circular satellite speed in the opposite direction.
I suppose this is do-able, it just takes a lot more fuel. But even if you do that, closing speed is going to be about 16 km/sec. with your target. That's about 36000 miles per hour. Guidance becomes a real issue at those speeds--there's not much time to correct, and satellites are small.
Even an orbital rendezvous is difficult, as they found with Apollo VIII (I think). To end up in the same place in the same orbit, starting in the same orbit, the trailing capsule had to actually slow down, dropping to a lower orbit, speed back up to circular satellite speed, catch up with the lead capsule, accelerate to gain altitude, then slow back down to circular satellite speed for that orbit. Hitting something with any speed is more difficult. Even coming at it head on...I'm just not sure how easy it can be done. The USAF had an ASAT program back in the 80s that was launched from a fighter, but to my knowledge, we're the only country with guidance systems able to make the rendezvous, and even that had and explosive warhead, as I recall, obviating the need for a direct hit.
It's just not as simple as all those space movies have led us to believe.
--Ribald
Hey smarty pants,
all orbits decay
Even geostationary? At 36000 km?
Not very fast, no, but they do decay. Gravitational effects of the sun and moon also disturb orbits.
Not very quickly, mind you, but there is a lot of space way out there.
"No actual space war even has to be fought," Primack said. "Any country that felt threatened by America's starting to place lasers or other weapons in space would only have to launch the equivalent of gravel to destroy the sophisticated weaponry."
True in theory, but the application is a bit harder.
It's actually getting the 'gravel' to hit the satellites. Needs a pretty good guidance system to hit something the size of a few basketballs (though large solar arrays make it a bit easier), especially when it's moving at 8000 m/s. Not many people have inertial guidance systems this good (I work for a company that does make them)--I believe all that do are our allies. GPS gets tricky the higher you go, and doesn't really have that accuracy level, anyway, especially if you don't have the crypto to get the Y-code PPS signal.
"So we just put a big gravel cloud in front of the satellite, and it will tear itself apart!", you may say. Only problem here is, if you put it in the same orbit, it has to be going the same speed. Faster, it goes into a higher (elliptical) orbit. Slower, it goes into a lower (also elliptical) orbit, and likely burns up in the atmosphere.
Orbital mechanics is all pretty straightforward, and the math hasn't changed much in a couple hundred years. It's just not the same as shooting an airplane down with a missile. The intercept velocities are much, much higher, maneuvering on-orbit is a slow process, and you don't have the aerodynamic forces of lift and drag to help you out.
--Ribald
Many Intelligence satellites are in a low altitude (150-300 mile) polar orbit. Reading newspapers from 22,000 miles (geosync) just can't be done yet.
Not to mention the fact that a GEO bird would always be looking at the same thing. Put it in LEO, and it'll eventually be over what you want to look at.
You don't want to be burning the hydrazine all the time moving an intel sat around. They don't carry much (launch weight restrictions), and once it's gone, you can't even do attitude corrections anymore.
--Ribald
Junk deorbits rapidly. The square-cubed law means that they have higher surface area for their weight, and therefore proportionately higher atmospheric drag. Massive amounts of junk pumped into low orbits would be gone in months. In very high orbits (like geosync, not sure about the GPS orbits) it's a different situation, but there's also a lot more space at that distance.
Very likely true.
People seem to have a great misconception about 'space junk' running into important stuff. What most people don't realize is that in any given orbit, all satellites are moving at the exact same speed. They have to--it's basic physics and orbital mechanics. Pick up a copy of Bate, Mueller, and White if you don't believe me.
If it's in LEO (low earth orbit), in a circular orbit, it's going roughly 8 km/sec. Slow it down, it drops to a lower orbit, drag increases, it falls lower, and burns up. Speed it up, it goes into an elliptical orbit. Granted, this elliptical orbit may intersect with the orbit of another object, and theoretically collide, but there's a lot of room in space, and a bolt flying around has to get pretty lucky to nail a satellite. In all likelihood, this new elliptical orbit will intersect with the atmosphere at some point, start slowing down, and eventually spiral in.
The GEO birds are a lot farther out--6.5 Earth radii, as I recall (GPS is roughly half-sync, BTW, so figure half that). As the previous poster said, there's a lot more room out there.
At any rate, when stuff blows up in space, the debris cloud generally stays in the same orbit as the original satellite, and spreads gradually. 8km/sec is the driving variable here. Sure, if two satellites collede at obtuse angles (not very likely) (or one gets hit with a missile coming from the opposite direction), the debris is going to spread out. Some small bit will probably end up in a circular orbit (if it's a GEO bird, but I don't think missiles will reach that far), most will decay into the atmosphere, and some might go into HEO (higly-elliptical orbit). Get it going faster than 11.2 km/sec, and it's gone for good.
We're not going to have a cloud of debris constantly orbiting our planet after some kind of space war. I can't see how any appreciable amount of it would end up in a stable circular orbit, much less a low orbit--anything that gets accelerated in a collision/explosion will need a second acceleration to stabilize into a circular orbit at another altitude. The elliptical stuff will almost certainly all run afoul of the atmosphere.
Sure, some bigger chunks might manage to smash into our homes, but we're not going to be trapped for millennia...
--Ribald
Satellite seeking missiles aren't the easiest (or cheapest) weapons to build. As far as I know, the USAF is the only organization to ever construct one, namely the ALMV.
A very large missile launched from an F-15 in a ballistic climb, the project was canceled due to cost. I believe they did test some of these, and might even have some in a bunker somewhere, but I can't find a source on that.
--Ribald