In-Flight Reboot? 594
steelem writes "The Washington Post is running a story about how the F-22 Raptor's software requires in-flight reboots. Apparently the 2 million line software project is 93% done. Knowing most projects I've been on, it'll stay that way for another few years."
LinuxBIOS in flight computers (Score:4, Interesting)
Nasa has an interesting project called FlightLinux [nasa.gov] specifically geared for this sort of application. Unfortunately, they have yet to release code (export restrictions), but they supposedly use LinuxBIOS for their system.
Of course, having software that never crashes (no pun intended) would be best, but it never hurts to have a system that can boot up in just a couple seconds anyway.
What do you expect (Score:3, Interesting)
Why reboot systems at all? (Score:5, Interesting)
Why is this a big deal? (Score:5, Interesting)
Flight control software has been rebootable on the fly since the earliest days of the space program.
Ejection Seat (Score:3, Interesting)
Disturbed (Score:1, Interesting)
Question to physicists/biologists/chemists: Would you have a problem creating and refining nuclear/biological/chemical weapons?
(Posted anon. to avoid the right wing moderators killing my account.)
Re:Remarkably frank ... (Score:3, Interesting)
What disturbs me too is slashdot reporting. The article wasn't "about" the system needing reboots in flight, that was just one thing mentioned. The article was "about" a piece of military hardware nearing completion. The slashdot front page description and the real article may as well have been about two entirely different subjects for all they share.
This isn't a big deal (Score:5, Interesting)
Re: Editors, upon submission... (Score:4, Interesting)
> Please consider having Slashdot do a quick search, esp in the last 2-3 weeks. Even if this is done at the submittor level, then they could avoid this. I have no doubt that most submittors would prefer to avoid this.
Au contraire, I would guess that every time a story hits Slashdot about 9000 clowns immediately submit it again in hopes of duping the editors into a dupe.
Apollo 11 (Score:5, Interesting)
You can read more here [nasa.gov].
written in ADA ! (Score:2, Interesting)
Some clarification... (Score:1, Interesting)
There are typically 2 (sets of) computers on board these aircraft.
The "flight control computers" actually fly the airplane. They are very reliable and are triply or quad redundant. They constantly monitor themselves for problems (such as bits changing in the onboard ROM chips). They reboot themselves if needed (which seldom happens). The "operating system" is just another piece of custom code. They are often compartmentalized so that a problem in one area of the computer (hardware or software) will not affect (or will have limited impact) on other more critical components.
The "mission computers" are not designed to the same standard and may have none of the aforementioned features. They try to do complex things like target identification etc. When they fail, they can take out other connected systems, like the radios or displays - but you can still fly the airplane. In one of the machines I worked on, they had to install a button in the cockpit so the test pilots could reboot the mission computer!
I don't know why we as an industry tolerate this situation (OK, I do - to save money). Test pilots are (understandably) very unhappy with the lack of reliability in these systems. As I'm sure most people reading this will realize, its a lot harder to fix a complex bit of code than it is to design in reliability in the first place.
And BTW, it was mentioned above but not everyone read it: it doesn't take 36 seconds to reboot the computer. The article meant that over the course of a 1 - 2 hour flight, 36 seconds were spent rebooting the computer
Cancel this project now (Score:4, Interesting)
Why? It's a problem program. It's been plagued with an abundance of serious unforseen engineering problems from the very beginning. This is just the latest one made public. Past problems have included repeated instances of various parts of the fuesalage (especially some wing and tailparts) cracking. Cost overruns have become endemic. When the ATF program (Advanced Tactical Fighter) was first launched in the mid-80's to find a successor to the legendary F-15 Eagle, the Air Force set a goal of a flyaway cost of no more than 35 million per copy. The cost is now up 200 million a copy, and before it goes into production, the F-22 might cost a quarter of a billion dollars FOR A SINGLE FIGHTER. No matter how rich a nation is, no Air Force in the world can afford to buy such fighters in effective quantities. Not even other Stealth projects have spiraled this far out of control. The F-117 NightHawk stealth fighter (really more of a small bomber), with a small inefficient production run of 64 aircraft, topped out at 61 million per copy.
Granted, not all of the cost overrun problems are the fault of the Air Force or of Lockheed Martin. Congress keeps screwing around with the production schedule, and reducing the total buy, which drives up the cost per aircraft. But Congress has done so in large part for three main reasons:
1- They ask "Do we really need this, or can upgraded F-15's do the job?" This is a valid question as no other nation, friend or foe, has an aircraft that equals the Eagle, save for Russia's SU-27 series of fighters. These have been produced in such small quantities that Congress still debates the need for an Eagle replacement.
2- The number and seriousness of technical problems has made Congress reluctant to commit to the project fully. This crosses party lines, as in the past few years, several powerful Republicans have tried to kill the program on the grounds that the Raptor is a lemon. Democrats seeking money for non-defense programs have joined them.
3- There are serious doubts emerging that the Raptor's massive complexity can ever truly be managed in an efficient manner. There are concerns that, even if the aircraft becomes operational and initial bugs are worked out, the aircraft will be unreliable, becoming what the Air Force calls a "Hangar Queen"; it looks pretty on the floor, but if it can't go up in the air regularly, how good is it? The Air Force has had aircraft before that they REALLY wanted, but turned out to be so expensive and maintenance intensive that they had to be retired early. And excellent example is the B-58 Hustler supersonic bomber, which had impressive performance...when it wasn't broken down. It was retired after only 10 years of frontline service.
Re:LinuxBIOS in flight computers (Score:2, Interesting)
Given the cost of one of these things, they are certainly not going to trade safety and reliability. Military systems are designed to have redundant systems because they will be deployed in harsher conditions than civilian aircraft.
Re:This has been coming for a while (Score:1, Interesting)
One of the interesting ideas I've heard has focused on making recovery from errors an integral part of the software design at every level. To an extent, safety-critical systems already use a number of techniques to recover from errors, rather on relying on perfection on the part of the human programmers (which is a pretty silly bet to make).
Just think about how you go through your own life. The human "operating system" isn't 100% perfectly reliable, but it's very robust at recovering from errors. Instead of striving for an impossible goal like perfection, systems are being designed to be less brittle. This approach is both more pragmatic and more robust, oddly enough.
Su-30 series or Quality/Quantity (Score:5, Interesting)
In pure features the Su-27 is an amazing plane. Anyone who has ever seen the Su-27 do the cobra [lucia.it] manouver or the thrust vectored Su-30MKI or Su-35 do the 360 degree Kulbit manouver can attest to what these planes can do in close air combat. These are extreme manouvers that western planes cannot do for the simple reason that the engines in western planes receive no air at such high angles of attack and therefore often flame-out or stall. Not only this but the newer radars on the Su-30s and missiles are longer ranging than just about anything the west has with the exception of the F-14's AIM-54 Phoenix. As for stealth, newer Su-30's are coated with radar absorbant paint which reduce the advantages that a dedicated stealth fighter such as the F-22 would have in BVR combat.
In the hands of a good pilot I very much doubt that the Su-30 would automatically lose in combat. That however is the crux of the matter: Pilot training.
This has always been something that has been much better in the west with advanced simulators, top gun style combat training and long hours of aircraft experience. It is and has been a fallacy to believe that more modern high tech will always win the battle. It is almost always the quality of the pilots that decided the battle.
There is a good example of an air combat situation atht happened in the first gulf war. The only western plane to be shot down in air combat was an F-18 on an attack mission that was intercepted by an obviously experienced Iraqi Mig-25 pilot. The Mig-25 was already obsolete then in terms of technology but the sheer speed of the plane (Mach 2.8+) is unmatched by any other fighter. The Mig-25 went on after shooting down the F-18 to buzz an EF-111 raven that was providing ECM for the mission causing the raven to have to manouver to avoid the incoming missiles and drop back from the attack mission which was then unprotected by ECM and subsequently another F-18 was shot down by a SAM. No less than two F-15's and two F-16's all attempted to intercept the Mig-25, two of them firing missiles, but the Mig-25 used it's tremendous speed advantage to easily avoid the interceptors and reach its base.
This shows what a good plane , not necesserally the utterly most modern, can do in the hands of a good pilot. IMO the F-22 is an overexpensive white elephant.
Re:Cancel this project now (Score:4, Interesting)
In other words, don't buy Raptors: buy the engineers, and let them try again, the wiser for the experience.
Re:LinuxBIOS in flight computers (Score:4, Interesting)
Re:LinuxBIOS in flight computers (Score:1, Interesting)
Money.
Maybe because the Pentagon has too much money. The recently approved defense budget is $400 billion, not including the continuing cost of the wars in Afghanistan and Iraq and whoever we invade next.
Is this money for the "war on terror"? Nope, as the first figure on this page [d-n-i.net] shows, most of the recent increases in the defense budget occured before 9/11/01.
Further down the page, you will see how the Pentagon can't even pass a minimal annual audit, how increases in the defense budget create pressure for more increases into the future, and how pre-production cost estimates are usually much lower than the actual cost. This is particularly relevant today as there are many projects in the pre-production stage now.
This information was put together by Chuck Spinney, who worked in the Pentagon's Office of Program Analysis and Evaluation for over 30 years.
Nothing new here (Score:4, Interesting)
This was 1980.
It got fixed.
-dB
Re:Faulty specs (Score:3, Interesting)
This individual claimed that most of the mishaps she was aware of that were attributed to software were in fact due to faulty system requirements, and I have no reason to doubt her. Unfortunately I don't remember any specific cases that she cited.
Re:WRONG (Score:1, Interesting)
If you insist...
Slackware for iBook [nathanr.net]
Slackware for Sparc [netunix.com]
Slackware for PC [slackware.org]
Re:LinuxBIOS in flight computers (Score:2, Interesting)
If you want software that does not crash during operation, you have to remove subroutine recursion and dynamic memory allocation so that you can guarantee an upper bound on the stack and pool usage at any time. If you're using multiple processes then you need some way of preventing deadlock and livelock. Whether you use C, C++ or Ada, you have to enforce these conventions in some way.
See the SPARK Ada site [sparkada.com] for an example of how you do this. But fundamentally, to write software that is crash free you cannot take an off-the-shelf language and off-the-shelf OS and simply hope for the best.
Re:Su-30 series or Quality/Quantity (Score:2, Interesting)