The 68010, the 68020, the 68030, the 68040, and the 68060 all changed the instruction set.
I beg to differ. There was one small change in the instruction sets, but this change would have been totally transparent to any user program running on the processor because it would have been trapped and emulated by the operating system anyway. Motorola did ADD additional op-codes in unused space, but those would have been transparent to existing programs too.
On the 64 bit... I believe that I was mistaken on the number of bits. The issue was 32 bit addressing. The X86 has some hokey register overlay scheme that I found objectionable and not easy to expand. It is what lead us to the 640K memory limits in DOS and some seriously stupid memory mapping legacy issues. (Don't get me started on the direct IO garbage.) The 68000 series started out as 16 bit devices and could run on as little as 8 address lines, but the architecture fully supported and was program compatible with the full 32 bit implementation. The 68000 series would have easily expanded from 8, 16 to 32 bits of address space in the hardware and we would have avoided all the DOS highMem junk and TSR program loading we had all that fun with back in the day.
But I do think that the memory mapped I/O approach of Motorola was a much better and more flexible way to do interfacing as was the interrupt handling and memory management schemes. Intel had to retrofit all this into their processors and chip sets trying to keep backward compatibility, where Motorola had all that designed in (albeit not implemented initially). I think the Motorola approach would have been more easily extended to 64 bits, but I guess that is just supposition on my part.
The reason for Intel and X86 is the IBM PC and it's back room marriage to Microsoft basically boiled down to a simple choice of who would supply the microprocessor with the most desirable terms. Intel won, with their X86, not because it was better or faster, but because they agreed to IBM's terms. The rest of the history is about the symbiotic (some would argue incestuous) relationship between Microsoft, Intel, and PC manufacturers has little to do with what would have been better technically.
The Motorola 68000 series processors where much more capable, flexible and MUCH easier to program (at least at the assembly level). Had Motorola won, we would have enjoyed an instruction set that did not change for the life of the 68000 processor. But as it was, with the x86 progression, 286, 386, Pentium and following, each introduced multiple instruction set alterations in an effort to keep up with the PC's needed expansion and performance requirements. None of this would have been necessary with the 68000 through the same progression.
Another advantage of the 68000 would have been 64 bit floating point math would have been standard and using 64 bits would have been seamless to the programs that used it. Operating systems would have been easily ported to 64 bit hardware, because it would have been a device driver exercise, and ONLY for devices that required 64 bit so the migration would have been piecemeal instead of the hard cut to 64 bit we have now.
We are stuck with x86, not because it was or is the best, but because it was the chosen one. X86 is the one supported by IBM back when this all got started, and now it's the primary platform for Windows and Microsoft. These past decisions where for business reasons and not technical ones. There is a lesson in all this..:)
So.. As long as the relationship between Microsoft, Intel and Hardware builders remains in tact, and the PC remains the premier computing platform, we will be stuck with the x86. The question is how long will this last? Apple tried and fell back to x86 hardware, but I'm not sure Intel is going to control the mobile computing market which seems to be able to make inroads into the desktop market.
Although natural gas is now very cheap, you would still have to import scads of it to generate electrical power enough to supply what Japan lost when it shut down the atomic energy industry. In addition, you would need to build the generation capacity to replace the nuclear power plants. Therefore, I believe that the restarting of many nuclear power plants is necessary.
Nuclear is not any more dangerous than much of the alternatives out there so this is NOT a bad thing. It's the market providing electrical power in the most cost efficient and timely manor possible, in a country that needs cheap and abundant power to recover. Hopefully they have fixed any systemic issues in their government oversight program and can avoid future issues, but these kinds of issues are not about nuclear power, but effective government.
Good for Japan! Now lets start building some safer plants and really do this right..
There isn't anything "digital" about a chair that needs rights management. You cannot use a chair multiple times by making a digital copy of it, nor can you transfer a digital copy of your chair to your friend. In fact the ability to use a chair requires that you physically have it. Now if this "rights management" somehow prevented you from making a *copy* of the chair, then it might be some kind of example, but it's certainly NOT an example of DRM.
Takes huge radars pumping lots of power into huge antennas and lots of processing power to be able to track a target the size of a missile heading towards you. (Look at the pointy end of a tooth pick and think about how much RF is going to be reflected by a missile) Then, you have to have a gun (more weight) and ammo (even more weight) with the ability to aim it (even more weight) and all this is going to have to work at really low temperatures while experiencing 8 G's or more (really complex). Further, you are going to have to intercept the pointy end of an object that is moving at nearly mach 5 at a distance that is great enough that there is a good chance the shrapnel sized pieces of metal and plastic created it comes apart miss the aircraft you are trying to protect.
This weight may make sense for a transport or heavy bomber, but in a fighter, weight is one of the basic physical constraints on performance. Heavy aircraft require more wing area, more wing area means they are going to be longer, which means more drag, lower roll rates and a host of performance bills to be paid. Designers must be extremely careful with a fighter's weight.
For the weight, Flares and Chaff are worth the weight because they are fairly effective on single missiles when used with the right maneuvers. Fighters can fly these maneuvers, transports, not so much... So a system like you describe, while possible, just isn't worth it for a small fighter or close air support aircraft.
I thought that the A-10 got retired basically because they flew the wings off of them, like they did the A-6's and F-14's. The airframes had so many cycles on them and the rigors of flying close air support strafing and bombing runs was taking their toll with fatigue starting to be a major issue with the all metal airframes. Instead of risking pulling the wings off and killing pilots, they retired the airframe. Of course the promise of the FA-18 taking over the same mission with a faster airplane and with the F-35 coming soon didn't hurt the "retire the A-10" idea either.
The F-35 is supposed to be an excellent dog fighter, an excellent A-t-A missile platform AND stealthy to boot. This makes it uniquely qualified to establish air superiority in a denied airspace (i.e. over areas controlled by the bad guys). The bad guys cannot see them on radar and unless they can get close enough to see them, won't have much hope of shooting them down. These planes basically are intended to go shoot down the opposition as quickly as possible and then fly CAP missions while other friendlies systematically destroy any ground based air defenses and aircraft on the ground. So you need F-35's to safely and quickly get control of an airspace, then you use cheaper F-16's and 18's to hold it while you dismantle the enemy's capacity to shoot down your close air support aircraft. We need them ALL (albeit in varying numbers).
True. I suppose I should have said, buy flocks of F-16's for fighters and FA-18's for general air cover and dropping bombs. Then have a few F-35's around for times when you don't have control of the sky yet and want to get the jump on the bad guys.
the problem is a real fight is done with air to air missiles, we have no use for fast muneverable stealthy planes when we have missiles that are faster than any plane, pull more gs than any plane, and can match the sensors of any plane. Why build a fighter when the missiles performance is such that you can engage the target before the plane sees it.
This is EXACTLY the thought process that brought us the boondoggle known as the F-4 Phantom. "We don't need to dogfight anymore, we have missiles that can shoot down the bad guy before anybody sees anybody else." They justified buying the F-4, with its updated missile systems, targeting radar, and blazing speed, that couldn't turn and didn't have a gun. Problem was though that missiles don't always work (actually quite often don't work) and after you miss you have a high probability of getting into a "dog fight" that an F-4 is unlikely to be able to win. F-4's are fast but they have high wing loading, high drag at high angles of attack and limited power so they turn slow. We paid the price for decades, flying the F-4.
We should not make the same mistake again... So I disagree with you on our need for a fighter. We need them.
What you say is somewhat true, but not exactly. Since the F-4 has been retired, we actually don't just do a fly by missile shot and run all the time.
Dog Fights can and do take place within visual range. The way this usually works is everything starts at radar range, somebody gets a missile shot from a distance. If that misses, or there are multiple aircraft, things can get pretty up close and personal pretty quick as things break down into a turning fight.. Where it is true that with today's aircraft, closure rates are extremely fast and altitudes are usually above 10,000 feet, it is not uncommon for a turning fight to be conducted within visual range. The winner of a turning fight is the aircraft that can maximize their turning rate (usually) and if you have a 6 G limit the best turn rate speed is going to be under 300 Knots (as I recall from the F-16). This gets everybody easily within visual range. You are correct though that if you are in a dog fight and find yourself at 5,000 feet you likely are in deep trouble and you should have already been looking for a way to exit the fight.
Of course the movies don't show all the details, and nobody would find it all that exciting trying to pick out the opponent who is 3-5 miles trying out turn you. Movies also drag dog fights out into long, expensive to shoot, sequences lasting way too long with multiple missile shots and gun bursts that far exceed the munitions you would likely have loaded. You can have long fights, but most are over in mere seconds, which doesn't make good film.
- Air to Ground. Yes, the drone can drop a hellfire or two. Absolutely worthless compared to an A-10. (Of course, we don't really have anything that is an upgrade to an A-10 but that's another issue). The current crop of drones are capable of blowing up fragile little meat popsicles but not a whole lot beyond.
Yes, eventually we will have mecca wars with no humans involved. But not just yet.
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Just to be as accurate as possible.... An A-10 is NOT designed for the fighter role. It is an "attack" role airframe, specifically designed for attacking armored ground targets in this case. It's not that an A-10 cannot be used for ACM, or that the pilots don't train for air-to-air situation, it's just not it's role and wasn't designed for this kind of thing so it pretty much sucks as a fighter.
How can you tell? Well, in the US we use the first letter to designate an aircraft's role. "C" - Cargo (C130, C5 etc), "A" - Ground Attack/Close air support (A10, AV8B, A-4, etc), F - Fighter (Air to Air platform, F-4 F14, F16, F-18 etc), "O" - Observation (OV-10) , T = Trainer, K = Tanker. Some aircraft have two letters. FA-18 means an F-18 outfitted with Ground Attack capacity that can still do Air to Air missions.
at some point the older aircraft become too expensive to maintain, rebuild, retrofit, etc. and airframe and everything else wears out. electronics die. less parts means it costs more per part.
I'm not sure I can agree with you. We are not talking about a TV or a Stereo where it is cheaper to throw it away than repair it. If you have an airframe that is not starting to come apart from fatigue in too many places and still is capable of performing the mission, it's going to be much cheaper to design a modern avionics package and retrofit your airframes over just building new. The B-52 is a prime example of such. That aircraft has been flown, in combat, since the 50's. They've stripped them down to bare rivets, rewired them, fitted new engines and modified them many times in the last 60 years, and likely will continue doing just that long after the first pilots to fly them are dead and gone. This retrofit and rework is WAY cheaper than starting from scratch.
Fighter aircraft are a bit different than a B-52. Their airframes suffer from fatigue issues (especially the Navy's stuff) and have to be scrapped sooner, but even the Navy can get a few decades out of an airframe, so you should figure on at least two tech refresh cycles on any airframe purchased today. Reworking the electronics is *CHEAP* compared to a whole new aircraft design. Even fly by wire aircraft controls can be reimplemented much cheaper the second time because all the air tunnel, flight test data and a working example system will already exist.
So, if you cannot find electronic parts for some old aircraft anymore, it's likely that the manufacturer can design up a whole new electronics package that is lighter, uses less power and is more capable than what you have at a fraction of the cost of designing and buying new airplanes. Any mechanical parts are usually pretty easy to manufacture, even in small numbers and I'll bet the manufacturer still remembers how. They might not want to build you a new airframe, but I'll bet they can manufacture any smaller parts you need or help you find serviceable parts in the scrap yard.
Commercial aircraft have a little different general life cycle, but they too are routinely stripped down to the bare airframe to have new electronics and mechanical systems upgraded/replaced. What usually kills a commercial aircraft design is advancements in fuel efficiency or operating costs improvements, that simply cannot be accommodated in the old airframe. Aircraft like the 737 prove that a good solid airframe can go though multiple redesigns much cheaper than trying to reinvent the whole thing.
No, redesign and retrofitting of aircraft is not more expensive than buying new, it's cheaper. Much cheaper.
I have often have doubts whether these fighter planes really have any use nowadays. Especially dogfighting seems to be a bit outdated in times of cheap shoulder launched surface to air missiles.
Dog fighting outdated? Not so fast!
Those who don't know history, are bound to repeat it.
The art of the dog fight has been dismissed as unnecessary before. Military planners who thought they knew, dismissed the need for dog fighting by saying "Hey, we have missiles and radar, nobody is going to dog fight anymore!" Poof! We got the F4 Phantom, which was a great interceptor with a really powerful radar, but a less than ideal platform for dog fighting. You could quickly get your opponent in range, but you had better kill him with the first missile shot because if you got into a turning fight with most of the opposition, you where going to loose in the bulky F4. We adjusted tactics and used the F4 high speed to swoop in, shoot a missile and bug out at Mac 2 before getting shot at. Didn't always work that well, but it helped keep the kill ratio up. We struggled with that oversight for decades until the F-16 came along and fixed the problem and allowed us to dog fight again.
History teaches that Air superiority requires both advanced missile technology AND superior dog fighting capacity. Stealth is a great feature, but it is only going to really help if you can shoot the opponent before he can see you. Once you are in visual range, you had better have the best sustained turn rate and a gun or you will loose (which is where the F4 failed).
You may not need flocks of F-35s, but having some is a good idea. Having flocks of F-18's is not a bad idea, as it's a fine dog fighter too. I vote we buy a mix of about 1 F35 to 4-5 F18's myself. But don't.. Please don't dismiss the importance of dog fighting to air power.
As in all things related to security, this is really a risk management question and may not be all that "crazy" in practice. I use a password storage program for my personal accounts so I can keep up with changing passwords on lots of sites. I keep the encrypted data file containing my passwords on my phone and automatically update a backup copy of the data file on my PC.
Yes, this is a risk, somebody could crack the encrypted password file and have access to my whole life. But what are the other options?
Write them all down? Paper is hard to keep updated and easy to loose.
Make them all the same? Obviously not a good idea....
Come up with some Common technique for password generation so all are different? Doesn't always work (Some sites have mutually exclusive password requirements) and doesn't allow passwords to get changed regularly.
I use a program to store my passwords on my phone, have my phone PIN protected and software to remotely wipe it. I keep an automated backup of the encrypted password data file. Should the phone go missing, step one is to wipe it, step two is start changing passwords. My biggest risk is somebody getting my password file and decrypting it without taking my phone, so I don't name it anything obvious and only transfer the data file on trusted network connections. Should the phone get lost/stolen, the crook will not have that long to 1. hack into my phone, 2. find the password file, 3. breach the encryption, 4. take over any or all of my accounts before I detect that the phone is missing, wipe it, change my passwords.
Are there risks with this approach? You betcha... But ANY approach has it's risks, it's all about understanding the risks and managing the risks to keep them at an acceptable level. I figure that I'm a whole lot better off than the average user out there, and should not be a huge target anyway.
And just kiss access to all these accounts goodbye? I don't know about you, but I have difficulty trying to remember 20 passwords with 20+ random characters.
Do change the E-mail address and make sure you have complex passwords that differ between sites. Complex Passwords are mixed case, have special characters, numbers and don't consist of dictionary words. Keep them as long as you can remember and keep them different between important sites. Change them regularly if you can.
Not really... Opportunity would not be well served by a huge increase in the dust falling on it, unless there was additional wind storms to keep it clean it would suffer from a reduction in power available. Further, adding a lot of fine dust to the surface would make driving more difficult. Where it would be fun to dream, I doubt Opportunity could survive an impact close enough to directly observe, or close enough to drive to with its remaining life.
You are correct.. My brain must be starting to go... After looking it up. Us Extras down to you technicians can blast away at 1500 watts on that band, assuming you needed that much power. But as you say, the RF safety issue is going to get pretty important.
Devices transmitting in the regulated bands (as opposed to unregulated space like the Wifi spectrum)....
Technically all of the spectrum is regulated. There is spectrum set aside for consumer use under various parts of the FCC's Rules, but there are regulations to follow even then. Most consumer devices operate under Part 15 rules, which generally regulates how much RF power you can radiate and stay legal, which boils down to "not much" and if you interfere with a licensed user you have to turn your stuff off.
By the way, there is at least one part of the WiFi spectrum that is actually allocated to Amateur Radio use. It is in the bottom of the 2.4Ghz band. (802.11b and up). Hams can use 100 Watts or more, where consumers are limited to Part 15 levels (about half a watt).
ever actually have to trace wires on an aircraft?
i've worked on Huey and Cobras...small helos. And they can be a PITA to track things down.
And yes, i've found things that were caused by miswired connections, usually in the solder terminals of a switch.
so yes, i can easily see something simple like putting the wrong wire into the wrong terminal of a terminal lug/connector as all it was.
wouldnt be the first time, just like it wouldnt be the first time a tech manual drawing was unclear or even incorrect.
As a matter of fact.. I have worked on aircraft some...
My point was that observing "blinking lights" on an aircraft is not proof of anything. It may be an indicator of where to go looking for a fault, but it's not proof. If there are incorrect terminations or shorts in the wiring, they will be physically observable and verifiable by inspection of the aircraft in almost all cases I can think of. Where is the "We sent our inspection team in and they found wire x crossed with wire y as it passed though connector z"? Or the technical critique of the design that says "Because wire x connects device y to device z you will see this undesired behavior when the aircraft is in such and such configuration"?
It still seems to me that somebody is applying pressure to get these aircraft airborne and we got some flimsy story about a wiring issue to explain why it's OK. I'm not saying it's not true, I'm saying we need to have proof that this is the problem, that the proposed solution will prevent future issues and that all flying aircraft have been properly modified before I'm for putting passengers in the air.
It shouldn't have been possible to "miswire" an aerospace battery, the connectors should have been coded, the wires, and the inspectors should have seen and tested this. Battery failure is still a process failure. Unfortunately, process failures are the most systemic failures possible. Lets hope I'm wrong....
andy
One must think about how aircraft are actually assembled. In most cases, wire bundles are installed without the terminating connectors installed on at least one end. This is because the connectors are too bulky to easily pull bundles though the small spaces required and it is difficult to know the exact length necessary to provide the proper clamping and clearances. It is simpler and cheaper to just install the wires and then cut them to length and install the connectors.
Manufacturing processes for aircraft usually include a comprehensive double check of wiring harness installation. This includes manual and automated testing using machines the connect to the huge number of connectors in a wired aircraft, followed by extensive functional testing of just about everything. Errors are not uncommon, but they are generally caught and corrected long before the aircraft gets signed off as airworthy.
Usually, manufacturing designs for aircraft include specific keying for connectors which might be miswired. This means that it would be impossible for an avionics mechanic replacing a battery to connect up something incorrectly, unless they altered the keying on the connectors or did something really stupid like re-routing an existing wiring harness to "make it reach". Both activities would be physically obvious.
Beyond routine maintenance, you have ongoing modification processes, where wiring can get changed due to design changes. This process is very strictly controlled and involves a verification process that should have independent review of all the work done. If someone miswired the aircraft, and the review missed it, then ALL three entities are going to be at fault. The guy who re-wired it, the guy who signed it off as complete and the manufacturer who designed the verification test. Assuming everybody was following procedure and nobody is guilty of not doing their job.
Again, this whole "it was wired incorrectly" idea sounds fishy to me given the "blinking lights" as evidence. Either the plane was wired wrong or it wasn't, and you can grab the design drawings and verify the wiring pretty quick. Now if they are saying there is a *design* issue, that too should be something that can be clearly explained by looking at the drawings. Reports of blinking lights might be an indicator of where to look, but it is not proof we found the problem.
I was just thinking that..the media will now have their blame game but at the end of the day it was a plane mishap that didn't include charred bodies strewn on the countryside. It was a glitch, that was easily fixed. I could have been much worse.
This whole idea of a wiring error sounds fishy and it seems to be based on flimsy evidence. These kind of things are proven by hard inspection of the aircraft, drawings, and designs not by observing flickering lights. Somebody in Japan wants these aircraft in the air really bad, and I'm betting they managed to talk Japan's version of the NTSB into this idea.
I'm waiting for the final report on this... Before I decide to get on one of these.. Because if this flimsy sounding reason is what I think it is, another plane is going to have a battery fire pretty soon and this time we might not be so lucky.
I'm skeptical of this story. They are basically saying that somehow the wiring got messed up in such a way that everything still worked, but the battery was improperly charged/discharged by the APU. The evidence they have is some lights that flickered. This seems fishy to me.
If something is miswired, then it's going to be possible to PROVE that as fact. Even if the unit was cut from the aircraft, it would be possible to physically inspect and verify what wire went where. Flickering lights are NOT PROOF of anything being incorrectly wired.
If the drawings don't match the design, you can PROVE that by inspecting the drawings. If the aircraft doesn't match the drawings you can PROVE that by inspecting the aircraft. We have NO proof here.
I'm guessing that somebody in Japan wants to get these aircraft back into the air, bad enough to come up with some story with flimsy evidence and managed to get Japan's version of the NTSB to agree.
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The 68010, the 68020, the 68030, the 68040, and the 68060 all changed the instruction set.
I beg to differ. There was one small change in the instruction sets, but this change would have been totally transparent to any user program running on the processor because it would have been trapped and emulated by the operating system anyway. Motorola did ADD additional op-codes in unused space, but those would have been transparent to existing programs too.
On the 64 bit... I believe that I was mistaken on the number of bits. The issue was 32 bit addressing. The X86 has some hokey register overlay scheme that I found objectionable and not easy to expand. It is what lead us to the 640K memory limits in DOS and some seriously stupid memory mapping legacy issues. (Don't get me started on the direct IO garbage.) The 68000 series started out as 16 bit devices and could run on as little as 8 address lines, but the architecture fully supported and was program compatible with the full 32 bit implementation. The 68000 series would have easily expanded from 8, 16 to 32 bits of address space in the hardware and we would have avoided all the DOS highMem junk and TSR program loading we had all that fun with back in the day.
But I do think that the memory mapped I/O approach of Motorola was a much better and more flexible way to do interfacing as was the interrupt handling and memory management schemes. Intel had to retrofit all this into their processors and chip sets trying to keep backward compatibility, where Motorola had all that designed in (albeit not implemented initially). I think the Motorola approach would have been more easily extended to 64 bits, but I guess that is just supposition on my part.
Gee.... And I thought mowing lawns for 3 summers for minimum wage had no upside beyond the paycheck. You are right, I DON"T want to go back.
The reason for Intel and X86 is the IBM PC and it's back room marriage to Microsoft basically boiled down to a simple choice of who would supply the microprocessor with the most desirable terms. Intel won, with their X86, not because it was better or faster, but because they agreed to IBM's terms. The rest of the history is about the symbiotic (some would argue incestuous) relationship between Microsoft, Intel, and PC manufacturers has little to do with what would have been better technically.
The Motorola 68000 series processors where much more capable, flexible and MUCH easier to program (at least at the assembly level). Had Motorola won, we would have enjoyed an instruction set that did not change for the life of the 68000 processor. But as it was, with the x86 progression, 286, 386, Pentium and following, each introduced multiple instruction set alterations in an effort to keep up with the PC's needed expansion and performance requirements. None of this would have been necessary with the 68000 through the same progression.
Another advantage of the 68000 would have been 64 bit floating point math would have been standard and using 64 bits would have been seamless to the programs that used it. Operating systems would have been easily ported to 64 bit hardware, because it would have been a device driver exercise, and ONLY for devices that required 64 bit so the migration would have been piecemeal instead of the hard cut to 64 bit we have now.
We are stuck with x86, not because it was or is the best, but because it was the chosen one. X86 is the one supported by IBM back when this all got started, and now it's the primary platform for Windows and Microsoft. These past decisions where for business reasons and not technical ones. There is a lesson in all this.. :)
So.. As long as the relationship between Microsoft, Intel and Hardware builders remains in tact, and the PC remains the premier computing platform, we will be stuck with the x86. The question is how long will this last? Apple tried and fell back to x86 hardware, but I'm not sure Intel is going to control the mobile computing market which seems to be able to make inroads into the desktop market.
Although natural gas is now very cheap, you would still have to import scads of it to generate electrical power enough to supply what Japan lost when it shut down the atomic energy industry. In addition, you would need to build the generation capacity to replace the nuclear power plants. Therefore, I believe that the restarting of many nuclear power plants is necessary.
Nuclear is not any more dangerous than much of the alternatives out there so this is NOT a bad thing. It's the market providing electrical power in the most cost efficient and timely manor possible, in a country that needs cheap and abundant power to recover. Hopefully they have fixed any systemic issues in their government oversight program and can avoid future issues, but these kinds of issues are not about nuclear power, but effective government.
Good for Japan! Now lets start building some safer plants and really do this right..
Digital Rights Management?
There isn't anything "digital" about a chair that needs rights management. You cannot use a chair multiple times by making a digital copy of it, nor can you transfer a digital copy of your chair to your friend. In fact the ability to use a chair requires that you physically have it. Now if this "rights management" somehow prevented you from making a *copy* of the chair, then it might be some kind of example, but it's certainly NOT an example of DRM.
You better sit down for this...... Oh wait....
Takes huge radars pumping lots of power into huge antennas and lots of processing power to be able to track a target the size of a missile heading towards you. (Look at the pointy end of a tooth pick and think about how much RF is going to be reflected by a missile) Then, you have to have a gun (more weight) and ammo (even more weight) with the ability to aim it (even more weight) and all this is going to have to work at really low temperatures while experiencing 8 G's or more (really complex). Further, you are going to have to intercept the pointy end of an object that is moving at nearly mach 5 at a distance that is great enough that there is a good chance the shrapnel sized pieces of metal and plastic created it comes apart miss the aircraft you are trying to protect.
This weight may make sense for a transport or heavy bomber, but in a fighter, weight is one of the basic physical constraints on performance. Heavy aircraft require more wing area, more wing area means they are going to be longer, which means more drag, lower roll rates and a host of performance bills to be paid. Designers must be extremely careful with a fighter's weight.
For the weight, Flares and Chaff are worth the weight because they are fairly effective on single missiles when used with the right maneuvers. Fighters can fly these maneuvers, transports, not so much... So a system like you describe, while possible, just isn't worth it for a small fighter or close air support aircraft.
I thought that the A-10 got retired basically because they flew the wings off of them, like they did the A-6's and F-14's. The airframes had so many cycles on them and the rigors of flying close air support strafing and bombing runs was taking their toll with fatigue starting to be a major issue with the all metal airframes. Instead of risking pulling the wings off and killing pilots, they retired the airframe. Of course the promise of the FA-18 taking over the same mission with a faster airplane and with the F-35 coming soon didn't hurt the "retire the A-10" idea either.
The F-35 is supposed to be an excellent dog fighter, an excellent A-t-A missile platform AND stealthy to boot. This makes it uniquely qualified to establish air superiority in a denied airspace (i.e. over areas controlled by the bad guys). The bad guys cannot see them on radar and unless they can get close enough to see them, won't have much hope of shooting them down. These planes basically are intended to go shoot down the opposition as quickly as possible and then fly CAP missions while other friendlies systematically destroy any ground based air defenses and aircraft on the ground. So you need F-35's to safely and quickly get control of an airspace, then you use cheaper F-16's and 18's to hold it while you dismantle the enemy's capacity to shoot down your close air support aircraft. We need them ALL (albeit in varying numbers).
True. I suppose I should have said, buy flocks of F-16's for fighters and FA-18's for general air cover and dropping bombs. Then have a few F-35's around for times when you don't have control of the sky yet and want to get the jump on the bad guys.
the problem is a real fight is done with air to air missiles, we have no use for fast muneverable stealthy planes when we have missiles that are faster than any plane, pull more gs than any plane, and can match the sensors of any plane. Why build a fighter when the missiles performance is such that you can engage the target before the plane sees it.
This is EXACTLY the thought process that brought us the boondoggle known as the F-4 Phantom. "We don't need to dogfight anymore, we have missiles that can shoot down the bad guy before anybody sees anybody else." They justified buying the F-4, with its updated missile systems, targeting radar, and blazing speed, that couldn't turn and didn't have a gun. Problem was though that missiles don't always work (actually quite often don't work) and after you miss you have a high probability of getting into a "dog fight" that an F-4 is unlikely to be able to win. F-4's are fast but they have high wing loading, high drag at high angles of attack and limited power so they turn slow. We paid the price for decades, flying the F-4.
We should not make the same mistake again... So I disagree with you on our need for a fighter. We need them.
What you say is somewhat true, but not exactly. Since the F-4 has been retired, we actually don't just do a fly by missile shot and run all the time.
Dog Fights can and do take place within visual range. The way this usually works is everything starts at radar range, somebody gets a missile shot from a distance. If that misses, or there are multiple aircraft, things can get pretty up close and personal pretty quick as things break down into a turning fight.. Where it is true that with today's aircraft, closure rates are extremely fast and altitudes are usually above 10,000 feet, it is not uncommon for a turning fight to be conducted within visual range. The winner of a turning fight is the aircraft that can maximize their turning rate (usually) and if you have a 6 G limit the best turn rate speed is going to be under 300 Knots (as I recall from the F-16). This gets everybody easily within visual range. You are correct though that if you are in a dog fight and find yourself at 5,000 feet you likely are in deep trouble and you should have already been looking for a way to exit the fight.
Of course the movies don't show all the details, and nobody would find it all that exciting trying to pick out the opponent who is 3-5 miles trying out turn you. Movies also drag dog fights out into long, expensive to shoot, sequences lasting way too long with multiple missile shots and gun bursts that far exceed the munitions you would likely have loaded. You can have long fights, but most are over in mere seconds, which doesn't make good film.
There are multiple roles for small fighter jets:
- Air to Ground. Yes, the drone can drop a hellfire or two. Absolutely worthless compared to an A-10. (Of course, we don't really have anything that is an upgrade to an A-10 but that's another issue). The current crop of drones are capable of blowing up fragile little meat popsicles but not a whole lot beyond.
Yes, eventually we will have mecca wars with no humans involved. But not just yet.
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Just to be as accurate as possible.... An A-10 is NOT designed for the fighter role. It is an "attack" role airframe, specifically designed for attacking armored ground targets in this case. It's not that an A-10 cannot be used for ACM, or that the pilots don't train for air-to-air situation, it's just not it's role and wasn't designed for this kind of thing so it pretty much sucks as a fighter.
How can you tell? Well, in the US we use the first letter to designate an aircraft's role. "C" - Cargo (C130, C5 etc), "A" - Ground Attack/Close air support (A10, AV8B, A-4, etc), F - Fighter (Air to Air platform, F-4 F14, F16, F-18 etc), "O" - Observation (OV-10) , T = Trainer, K = Tanker. Some aircraft have two letters. FA-18 means an F-18 outfitted with Ground Attack capacity that can still do Air to Air missions.
at some point the older aircraft become too expensive to maintain, rebuild, retrofit, etc. and airframe and everything else wears out. electronics die. less parts means it costs more per part.
I'm not sure I can agree with you. We are not talking about a TV or a Stereo where it is cheaper to throw it away than repair it. If you have an airframe that is not starting to come apart from fatigue in too many places and still is capable of performing the mission, it's going to be much cheaper to design a modern avionics package and retrofit your airframes over just building new. The B-52 is a prime example of such. That aircraft has been flown, in combat, since the 50's. They've stripped them down to bare rivets, rewired them, fitted new engines and modified them many times in the last 60 years, and likely will continue doing just that long after the first pilots to fly them are dead and gone. This retrofit and rework is WAY cheaper than starting from scratch.
Fighter aircraft are a bit different than a B-52. Their airframes suffer from fatigue issues (especially the Navy's stuff) and have to be scrapped sooner, but even the Navy can get a few decades out of an airframe, so you should figure on at least two tech refresh cycles on any airframe purchased today. Reworking the electronics is *CHEAP* compared to a whole new aircraft design. Even fly by wire aircraft controls can be reimplemented much cheaper the second time because all the air tunnel, flight test data and a working example system will already exist.
So, if you cannot find electronic parts for some old aircraft anymore, it's likely that the manufacturer can design up a whole new electronics package that is lighter, uses less power and is more capable than what you have at a fraction of the cost of designing and buying new airplanes. Any mechanical parts are usually pretty easy to manufacture, even in small numbers and I'll bet the manufacturer still remembers how. They might not want to build you a new airframe, but I'll bet they can manufacture any smaller parts you need or help you find serviceable parts in the scrap yard.
Commercial aircraft have a little different general life cycle, but they too are routinely stripped down to the bare airframe to have new electronics and mechanical systems upgraded/replaced. What usually kills a commercial aircraft design is advancements in fuel efficiency or operating costs improvements, that simply cannot be accommodated in the old airframe. Aircraft like the 737 prove that a good solid airframe can go though multiple redesigns much cheaper than trying to reinvent the whole thing.
No, redesign and retrofitting of aircraft is not more expensive than buying new, it's cheaper. Much cheaper.
I have often have doubts whether these fighter planes really have any use nowadays. Especially dogfighting seems to be a bit outdated in times of cheap shoulder launched surface to air missiles.
Dog fighting outdated? Not so fast!
Those who don't know history, are bound to repeat it.
The art of the dog fight has been dismissed as unnecessary before. Military planners who thought they knew, dismissed the need for dog fighting by saying "Hey, we have missiles and radar, nobody is going to dog fight anymore!" Poof! We got the F4 Phantom, which was a great interceptor with a really powerful radar, but a less than ideal platform for dog fighting. You could quickly get your opponent in range, but you had better kill him with the first missile shot because if you got into a turning fight with most of the opposition, you where going to loose in the bulky F4. We adjusted tactics and used the F4 high speed to swoop in, shoot a missile and bug out at Mac 2 before getting shot at. Didn't always work that well, but it helped keep the kill ratio up. We struggled with that oversight for decades until the F-16 came along and fixed the problem and allowed us to dog fight again.
History teaches that Air superiority requires both advanced missile technology AND superior dog fighting capacity. Stealth is a great feature, but it is only going to really help if you can shoot the opponent before he can see you. Once you are in visual range, you had better have the best sustained turn rate and a gun or you will loose (which is where the F4 failed).
You may not need flocks of F-35s, but having some is a good idea. Having flocks of F-18's is not a bad idea, as it's a fine dog fighter too. I vote we buy a mix of about 1 F35 to 4-5 F18's myself. But don't.. Please don't dismiss the importance of dog fighting to air power.
As in all things related to security, this is really a risk management question and may not be all that "crazy" in practice. I use a password storage program for my personal accounts so I can keep up with changing passwords on lots of sites. I keep the encrypted data file containing my passwords on my phone and automatically update a backup copy of the data file on my PC.
Yes, this is a risk, somebody could crack the encrypted password file and have access to my whole life. But what are the other options?
Write them all down? Paper is hard to keep updated and easy to loose.
Make them all the same? Obviously not a good idea....
Come up with some Common technique for password generation so all are different? Doesn't always work (Some sites have mutually exclusive password requirements) and doesn't allow passwords to get changed regularly.
I use a program to store my passwords on my phone, have my phone PIN protected and software to remotely wipe it. I keep an automated backup of the encrypted password data file. Should the phone go missing, step one is to wipe it, step two is start changing passwords. My biggest risk is somebody getting my password file and decrypting it without taking my phone, so I don't name it anything obvious and only transfer the data file on trusted network connections. Should the phone get lost/stolen, the crook will not have that long to 1. hack into my phone, 2. find the password file, 3. breach the encryption, 4. take over any or all of my accounts before I detect that the phone is missing, wipe it, change my passwords.
Are there risks with this approach? You betcha... But ANY approach has it's risks, it's all about understanding the risks and managing the risks to keep them at an acceptable level. I figure that I'm a whole lot better off than the average user out there, and should not be a huge target anyway.
And just kiss access to all these accounts goodbye? I don't know about you, but I have difficulty trying to remember 20 passwords with 20+ random characters.
Do change the E-mail address and make sure you have complex passwords that differ between sites. Complex Passwords are mixed case, have special characters, numbers and don't consist of dictionary words. Keep them as long as you can remember and keep them different between important sites. Change them regularly if you can.
Not really... Opportunity would not be well served by a huge increase in the dust falling on it, unless there was additional wind storms to keep it clean it would suffer from a reduction in power available. Further, adding a lot of fine dust to the surface would make driving more difficult. Where it would be fun to dream, I doubt Opportunity could survive an impact close enough to directly observe, or close enough to drive to with its remaining life.
You are correct.. My brain must be starting to go... After looking it up. Us Extras down to you technicians can blast away at 1500 watts on that band, assuming you needed that much power. But as you say, the RF safety issue is going to get pretty important.
Yep, it's called Part 15... And that means that the space really is regulated...
Devices transmitting in the regulated bands (as opposed to unregulated space like the Wifi spectrum) ....
Technically all of the spectrum is regulated. There is spectrum set aside for consumer use under various parts of the FCC's Rules, but there are regulations to follow even then. Most consumer devices operate under Part 15 rules, which generally regulates how much RF power you can radiate and stay legal, which boils down to "not much" and if you interfere with a licensed user you have to turn your stuff off.
By the way, there is at least one part of the WiFi spectrum that is actually allocated to Amateur Radio use. It is in the bottom of the 2.4Ghz band. (802.11b and up). Hams can use 100 Watts or more, where consumers are limited to Part 15 levels (about half a watt).
ever actually have to trace wires on an aircraft? i've worked on Huey and Cobras...small helos. And they can be a PITA to track things down. And yes, i've found things that were caused by miswired connections, usually in the solder terminals of a switch. so yes, i can easily see something simple like putting the wrong wire into the wrong terminal of a terminal lug/connector as all it was. wouldnt be the first time, just like it wouldnt be the first time a tech manual drawing was unclear or even incorrect.
As a matter of fact.. I have worked on aircraft some...
My point was that observing "blinking lights" on an aircraft is not proof of anything. It may be an indicator of where to go looking for a fault, but it's not proof. If there are incorrect terminations or shorts in the wiring, they will be physically observable and verifiable by inspection of the aircraft in almost all cases I can think of. Where is the "We sent our inspection team in and they found wire x crossed with wire y as it passed though connector z"? Or the technical critique of the design that says "Because wire x connects device y to device z you will see this undesired behavior when the aircraft is in such and such configuration"?
It still seems to me that somebody is applying pressure to get these aircraft airborne and we got some flimsy story about a wiring issue to explain why it's OK. I'm not saying it's not true, I'm saying we need to have proof that this is the problem, that the proposed solution will prevent future issues and that all flying aircraft have been properly modified before I'm for putting passengers in the air.
I agree.
It shouldn't have been possible to "miswire" an aerospace battery, the connectors should have been coded, the wires, and the inspectors should have seen and tested this. Battery failure is still a process failure. Unfortunately, process failures are the most systemic failures possible. Lets hope I'm wrong....
andy
One must think about how aircraft are actually assembled. In most cases, wire bundles are installed without the terminating connectors installed on at least one end. This is because the connectors are too bulky to easily pull bundles though the small spaces required and it is difficult to know the exact length necessary to provide the proper clamping and clearances. It is simpler and cheaper to just install the wires and then cut them to length and install the connectors.
Manufacturing processes for aircraft usually include a comprehensive double check of wiring harness installation. This includes manual and automated testing using machines the connect to the huge number of connectors in a wired aircraft, followed by extensive functional testing of just about everything. Errors are not uncommon, but they are generally caught and corrected long before the aircraft gets signed off as airworthy.
Usually, manufacturing designs for aircraft include specific keying for connectors which might be miswired. This means that it would be impossible for an avionics mechanic replacing a battery to connect up something incorrectly, unless they altered the keying on the connectors or did something really stupid like re-routing an existing wiring harness to "make it reach". Both activities would be physically obvious.
Beyond routine maintenance, you have ongoing modification processes, where wiring can get changed due to design changes. This process is very strictly controlled and involves a verification process that should have independent review of all the work done. If someone miswired the aircraft, and the review missed it, then ALL three entities are going to be at fault. The guy who re-wired it, the guy who signed it off as complete and the manufacturer who designed the verification test. Assuming everybody was following procedure and nobody is guilty of not doing their job.
Again, this whole "it was wired incorrectly" idea sounds fishy to me given the "blinking lights" as evidence. Either the plane was wired wrong or it wasn't, and you can grab the design drawings and verify the wiring pretty quick. Now if they are saying there is a *design* issue, that too should be something that can be clearly explained by looking at the drawings. Reports of blinking lights might be an indicator of where to look, but it is not proof we found the problem.
I was just thinking that..the media will now have their blame game but at the end of the day it was a plane mishap that didn't include charred bodies strewn on the countryside. It was a glitch, that was easily fixed. I could have been much worse.
This whole idea of a wiring error sounds fishy and it seems to be based on flimsy evidence. These kind of things are proven by hard inspection of the aircraft, drawings, and designs not by observing flickering lights. Somebody in Japan wants these aircraft in the air really bad, and I'm betting they managed to talk Japan's version of the NTSB into this idea.
I'm waiting for the final report on this... Before I decide to get on one of these.. Because if this flimsy sounding reason is what I think it is, another plane is going to have a battery fire pretty soon and this time we might not be so lucky.
Who will it be? Maintenance? Boeing?
All of the above!
I'm skeptical of this story. They are basically saying that somehow the wiring got messed up in such a way that everything still worked, but the battery was improperly charged/discharged by the APU. The evidence they have is some lights that flickered. This seems fishy to me.
If something is miswired, then it's going to be possible to PROVE that as fact. Even if the unit was cut from the aircraft, it would be possible to physically inspect and verify what wire went where. Flickering lights are NOT PROOF of anything being incorrectly wired.
If the drawings don't match the design, you can PROVE that by inspecting the drawings. If the aircraft doesn't match the drawings you can PROVE that by inspecting the aircraft. We have NO proof here.
I'm guessing that somebody in Japan wants to get these aircraft back into the air, bad enough to come up with some story with flimsy evidence and managed to get Japan's version of the NTSB to agree.