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B-2 Stealth Bomber Gets Upgrade, Joins the '90s
WmHBlair writes "Flightglobal has a report about the upgrades being made to the B-2A Stealth Bomber, which include Pentium class processors, JOVIAL code rewritten in C, and fibre channel hard drives. The Register, as usual, makes light of this event with a tongue-in-cheek news item noting that the upgrade drags Stealth Bomber IT systems into the '90s."
While the headline might be good for a light giggle, there's a good reason why it's 10 years behind. Airplane avionics systems must be free of bugs, or people die. That especially goes for a plane that uses a flying wing design (which are historically hard to stabilize without computer control), and potentially carries nuclear warheads.
Not a typewriter
Having worked for a defense contractor (non-weapons, mind you) for 6 years, it doesn't surprise me at all that the technology for such things are at least 10 years behind state of the art. It takes so long to fully satisfy the requirements of a military contract, then it takes at least as long to fix all the little bugs that inevitably pop up after delivery; then there's the military amending their requirements halfway through the project, sometimes resulting in having to go almost all the way back to square one in the design cycle. Oh, and don't even get me started on requirements that belong in cartoons and comic books, not the real world of engineering.
imagine that in the future the enemy (whoever thinks they are the enemy and the others, who are not even aware that they maybe the enemy) will never know when they will get their shit kicked out of them due to a possible Pentium FDIV error or a buffer overflow of some sort. Let's just hope that any security bugs will be dealt with promptly, cause if they can hack into a computer because of some CPU errors by using java or javascript through a browser, the will certainly be looking for a way to control some more exciting equipment.
You can't handle the truth.
who modded that offtopic? It's clearly funny.
This is an interesting approach to security, use machines so old that no one can crack. Maybe that's why the Russians still use vacuum tubes in MiGs.
Maybe, or maybe they do it to protect their planes from EMP? http://en.wikipedia.org/wiki/Electromagnetic_bomb#Effects
It's "Pentium class", not "Pentium". I would bet my money on this comptuer being PowerPC based, probably PowerPC 74xx based, also known as "G4" of Macintosh fame. There are _a_lot_ of PowerPC based avionics, and cutting edge airplanes like Eurofighter, Gripen and F-22 have multiple PowerPC based systems doing all kinds of stuff. When doing embedded electronics for the military you are not going far pitching Intel stuff. You are going to use hardware from manufacturers that can guarantee parts that'll keep being manufactured over many years and are harndened to endure rapid heat, cold, moist and preassure fluctuations. Intel are doing commodity products for low end table environments. Look to manufacturers like Freescale for the stable and durable stuff.
- Henrik
- when the Shadows descend -
I wrote JOVIAL for 5 years, yes it's an old language, but it did have some quite neat features for accessing data really fast (memory overlays for example). NAS (National Airspace System) is written in JOVIAL and it does its job well enough. It's a good langauge for small memory footprints and usually all variables are global. I can't see what they are winning really rewriting it in C apart from introducing new bugs. There are JOVIAL to C preprocessors out there but they tend to produce sucky non maintainable code of course.
http://www.jovial.hill.af.mil/
Well, given this http://www.sandia.gov/LabNews/LN12-18-98/intel_story.htm was in 1998, and about 10 years of development and testing, I guess we're finally seeing CPU's on the B2's that will actually allow them to fly through some of the massive radiation/electrical crap that they would be generating.
www.christopherlewis.com
Are you sure? Software tends to be written by developers, and its the quality of them, their ability to work to quality standards and basically take their time to get it done right that matters. All that C code you've seen crash - it'll be because someone hacked it together, no-one tested it thoroughly enough, and no-one took the time to do it right. C is even easy to code reliably if you impose some restrictions on yourself (or use some libraries/routines that you can't easily take shortcuts with - eg if you can pass a pointer to a routine, you're going to pass a bad one one day, do some wrong arithmentic on it, etc. If you pass a strict fixed-size buffer, then you're much less likely to get an error. Just a simple example).
The point is you can write bad software in any language, the new C# stuff at work crashes all over the place and is slow. The old C code from 1984 is still working fine. Its not these languages that had anything to do with their relative quality.
eg. Spacecraft are written in C, and they've worked better than anyone expected:
The only reason I brought that up is because one of my editors said, Oh look, they have Java on this thing.
Oh, Java. Well, we have Java in the ground system not onboard the spacecraft.
Right. That's what it's starting to sound like.
That's right. Yeah. The spacecraft software is entirely in C.
C? Really? That surprises me a little bit.
Yes. It's entirely in C.
I thought Lockheed Martin was a big ADA shop for this sort of thing.
ADA is used largely in military applications, but JPL at any rate has moved away from ADA. Cassini, I believe, would be the last JPL mission that used ADA. And that was largely due to the success of the Mars Pathfinder in the mid-nineties. And as I said, these missions are to a large extent all derived from Mars Pathfinder.
After that successful mission, you say, Hey, we could do it in C now. That's not as scary as everybody thought?
Yeah. Right.
http://en.wikipedia.org/wiki/Pentium_FDIV_bug
Sig withheld to protect the innocent.
It essentially is Algol. JOVIAL stands for "Jules Own Version of IAL". IAL was at one point the name for Algol.
General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
Well, don't forget the Serbs managed to shoot down an F-117 during the showdown with Milosovic, and that was using stuff that was probably equivalent to what the Iraqi's had.*
However, you're not quite correct to the best of my knowledge. Stealth doesn't make things invisible to radar...it makes them harder to see. There's a lot of factors involved, but generally they boil it down into a factor called radar cross section (RCS). This is the size of a typical reflector that would produce the same radar return as the plane in question. A B-52 has a radar cross section the size of...well...a B-52 (not quite actually, but we won't get that deep into it). The B-2, on the other hand, has been said to have a radar cross section of a sparrow. You reduce the radar cross section mainly in two ways: by absorbing the radio wave (materials) or by reflecting it a different direction than straight back (geometry). This means that the way the plane is facing is important, because they're not spheres. If you get an aileron facing flat at a radar, they'll probably see you.
Now remember radar return above. You need enough radar return for the receiver to detect it. As the RCS gets smaller, the return drops, so you need a stronger signal to reflect off it, and/or a more sensitive receiver. A shorter distance means a stronger signal, due to the inverse square law. What the story likely refers to is stealth aircraft passing close enough to British frigates to be detected despite being stealthy.**
* I believe the Air Force concluded the F-117 was shot down by one of several radar-guided missiles fired at it, being guided partially manually, with help from infrared tracking. The F-117 has features to reduce it's infrared signature, too, but I don't think the reduction is as significant in infrared as it is in radar. The Serbs may have gotten enough of a radar return that allowed them to point the missile and let it's infrared seeker lock-on. The F-117's probably also flew riskier routes than a non-stealth aircraft like the F-15E's would take. If it was close enough to the radar, it also might have been possible to shoot it down with a strictly radar-guided missile.
It seems the Serbian military paid attention to both the ineffectiveness of the Iraqi air defenses against the F-117 during Desert Storm, and to the thorough way in which the US focused on destorying those defenses early on, making air supremacy a given only hours after the first bombs fell on Baghdad. They were careful both to protect their radars and missile launchers and to employ alternate detection tools, especially the Mk 1 eyeball. ** The Russians claim they have a technique of finding stealth aircraft by looking for holes in expected radar returns (mountains, etc). That would take extra computer power and it seems to me it would only work effectively on low-altitude aircraft, so it might not be a significant blow to stealth technology. I've also heard some stuff about using two receivers to detect stealth aircraft, but there wasn't enough details to get an idea how it works and how effective it might be.
"The Stealth Bomber's mission is to deliver nuke bombs inside Soviet territory. It's not really that good at anything else. Though it does get used for other missions, since the US needs to justify spending $2.2 BILLION on each one."
It's quite good at dropping large bombloads on places, other than Soviet Union, that are defended by SAMs and radar-guided AAA, and avoid getting shot down.
No other aircraft in the world can do this. F-117 can do the "avoid getting shot down" part, but not the large bombload part.
The quote from Patton was also in a film: Patton (1970)
"Nobody ever won a war by dying for his country. He won it by making the other poor dumb bastard die for his country." -- General George S. Patton (George C. Scott)
Intel allowed the government to have a no-fee license to produce a radiation hardened Pentium chip. The article has some details on radiation hardening.
http://www.sandia.gov/media/rhp.htm
I've built replacement keyboard assemblies for one of the systems on that. Not sure which. It was a rf and fluid gasketed oversized heavy aluminum box. The actual keyboard was made by Cherry. I was so disappointed. It's like finding a Yugo engine in a Corvette. http://www.cherrycorp.com/
I'd go on a Vegan diet but the delivery time from Vega is too long. --brownkitty
I worked on a Navy jet upgrade about 10 years ago. It was a project to replace an antiquated (read that as "wire-wrap technology") autopilot computer with a brand-new, spiffy, fully digital autopilot computer. Of course, just like the B-2, it had to be a form/fit replacement.
I was shocked when, at the first design review, the contractor said they would be using an 80286 as the CPU. Remember, this is 1995. The 80286 was introduced in 1984. By 1995, the Pentium was the standard. So of course I asked "Why use such an older processor, when a newer one would be much much faster?"
Their answer was essentially one word.
HEAT.
The 286 had perfectly adequate processing power to run the fairly simple algorithms needed for autopilot and related functions, including all the error detection and fault logging, as well as the required 2x of government-mandated growth allowance (you MUST use less than 50% of clock times in your design). Using anything more high-powered would generate more heat (which must be dissipated somewhere in the closed environment), and use more current. On a 1960's era airplane, with Kapton wiring and its risk of insulation fires, and its limited power generation ability, you don't toss in higher heat and power requirements without VERY good reasons.
The result turned out to be perfectly adequate, and a vast improvement over the original design.
Let me toss out another interesting statistic. From what I remember from a recent brief, Boeing is right now delivering upgrades to its commercial airline fleet autopilot/navigation computers with 32Mb of data storage installed for the navigation database. Just 32Mb. That's what you're sitting behind in every Southwest or United or American flight you enjoy. With memory so cheap, why not put more in? Same logic, same ideas: for commericial and military programs, you don't overbuild a device just because you can. You'd better have a REALLY good reason to make a change.
We geeks tend to forget that overclocking and water-cooling and 8Gb RAM and 2-TB hard drives are thousands of times overkill for very many purposes.
--Brandon / Split Infinity Music