* software failure question @ 2001-04-07 5:44 tmoran 2001-04-07 10:22 ` chris.danx ` (3 more replies) 0 siblings, 4 replies; 16+ messages in thread From: tmoran @ 2001-04-07 5:44 UTC (permalink / raw) Anyone know where this came from? "In one infamous software error, a misplaced minus sign resulted in a fighter jet's control system flipping the aircraft on its back whenever it crossed the equator. " http://www.newscientist.com/dailynews/news.jsp?id=ns9999595 ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-07 5:44 software failure question tmoran @ 2001-04-07 10:22 ` chris.danx 2001-04-07 10:28 ` chris.danx 2001-04-07 13:16 ` Mark Biggar ` (2 subsequent siblings) 3 siblings, 1 reply; 16+ messages in thread From: chris.danx @ 2001-04-07 10:22 UTC (permalink / raw) > Anyone know where this came from? > "In one infamous software error, a misplaced minus sign resulted in a > fighter jet's control system flipping the aircraft on its back whenever > it crossed the equator. " This the article on that bloke's new system for natural language to program code? Sounds interesting. Why would a misplaced minus sign result in flipping an aircraft like this? I don't think the natural language system is going to stop errors like this. People will still need to tell it to be wary of the equator and check for such things. Anyway it's unlikely that people will use it in such areas for a long while (until it's proven reliable and correct). My penny's worth, Chris Campbell ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-07 10:22 ` chris.danx @ 2001-04-07 10:28 ` chris.danx 2001-04-09 15:24 ` Smark 0 siblings, 1 reply; 16+ messages in thread From: chris.danx @ 2001-04-07 10:28 UTC (permalink / raw) Besides i don't want to graduate and find there's no programming job out there for me. No fancy house, no fast car, no beautiful girl on my arm. <g> ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-07 10:28 ` chris.danx @ 2001-04-09 15:24 ` Smark 2001-04-10 13:31 ` Marin David Condic 0 siblings, 1 reply; 16+ messages in thread From: Smark @ 2001-04-09 15:24 UTC (permalink / raw) "chris.danx" <chris.danx@ntlworld.com> wrote in message news:QYBz6.3604$IP5.728688@news2-win.server.ntlworld.com... > Besides i don't want to graduate and find there's no programming job out > there for me. No fancy house, no fast car, no beautiful girl on my arm. > <g> > > Yeah, man, chicks dig programmers :) I'm still waiting on the first two, but I have three beautiful girls on my arms ... ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-09 15:24 ` Smark @ 2001-04-10 13:31 ` Marin David Condic 2001-04-10 16:01 ` Smark 0 siblings, 1 reply; 16+ messages in thread From: Marin David Condic @ 2001-04-10 13:31 UTC (permalink / raw) Yeah. That's why *I* got into engineering - to meet girls! (I'm wondering when that starts to happen? Is there a scheduled milestone for it? :-) I recall this cartoon that I think was originated by Kliban but maybe was redone by Sergio Argones in Mad Magazine. It depicts this slick looking guy in a double breasted suit surrounded by beautiful women admiring him as he's walking down the street. This cop is kicking this old blind guy into the street and yelling at him: "Out of the way you swine! An *Engineer* is coming!" (Or insert your profession as desired. Maybe I need a version that says "Ada Programmer".) I wish I could find a copy of it in .JPG format. It would make good wallpaper - symbolizing the high level of respect given to those of us in the engineering professions. :-) MDC -- Marin David Condic Senior Software Engineer Pace Micro Technology Americas www.pacemicro.com Enabling the digital revolution e-Mail: marin.condic@pacemicro.com Web: http://www.mcondic.com/ "Smark" <not.provided@all.com> wrote in message news:9ask6e$jgk3@cui1.lmms.lmco.com... > > > > Yeah, man, chicks dig programmers :) > > I'm still waiting on the first two, but I have three beautiful girls on > my arms ... > > > > ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-10 13:31 ` Marin David Condic @ 2001-04-10 16:01 ` Smark 0 siblings, 0 replies; 16+ messages in thread From: Smark @ 2001-04-10 16:01 UTC (permalink / raw) Luckily, I met my wife before I became a complete geek. I can't imagine going through all the hassles of starting a new relationship at this point ... and I am only 30! I recall a cartoon in, uh, another magazine, in which a guy is surrounded by beautiful, scantily-clad women, and he looks at his watch and says "Wait! Wheel of Fortune is on!" What a nerd ... now, if "Robot Wars" was on ... Mark "Marin David Condic" <marin.condic.auntie.spam@pacemicro.com> wrote in message news:9av1v3$n12$1@nh.pace.co.uk... > Yeah. That's why *I* got into engineering - to meet girls! (I'm wondering > when that starts to happen? Is there a scheduled milestone for it? :-) > > I recall this cartoon that I think was originated by Kliban but maybe was > redone by Sergio Argones in Mad Magazine. It depicts this slick looking guy > in a double breasted suit surrounded by beautiful women admiring him as he's > walking down the street. This cop is kicking this old blind guy into the > street and yelling at him: "Out of the way you swine! An *Engineer* is > coming!" (Or insert your profession as desired. Maybe I need a version that > says "Ada Programmer".) I wish I could find a copy of it in .JPG format. It > would make good wallpaper - symbolizing the high level of respect given to > those of us in the engineering professions. :-) > > MDC > -- > Marin David Condic > Senior Software Engineer > Pace Micro Technology Americas www.pacemicro.com > Enabling the digital revolution > e-Mail: marin.condic@pacemicro.com > Web: http://www.mcondic.com/ > > > "Smark" <not.provided@all.com> wrote in message > news:9ask6e$jgk3@cui1.lmms.lmco.com... > > > > > > > Yeah, man, chicks dig programmers :) > > > > I'm still waiting on the first two, but I have three beautiful girls on > > my arms ... > > > > > > > > > > ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-07 5:44 software failure question tmoran 2001-04-07 10:22 ` chris.danx @ 2001-04-07 13:16 ` Mark Biggar 2001-04-07 13:41 ` Larry Hazel ` (2 more replies) 2001-04-07 13:52 ` Ken Garlington 2001-04-09 18:13 ` Phaedrus 3 siblings, 3 replies; 16+ messages in thread From: Mark Biggar @ 2001-04-07 13:16 UTC (permalink / raw) tmoran@acm.org wrote: > > Anyone know where this came from? > "In one infamous software error, a misplaced minus sign resulted in a > fighter jet's control system flipping the aircraft on its back whenever > it crossed the equator. " It was the fly-by-wire software for the F-16. Fortunately, this error was caught in simulation and no planes were actually flipped. For more info, you might want to look in the risks-digest report database "http://catless.ncl.ac.uk/Risks". The bug in question can be found easly by searching on "equator". -- Mark Biggar mark.a.biggar@home.com ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-07 13:16 ` Mark Biggar @ 2001-04-07 13:41 ` Larry Hazel 2001-04-07 21:55 ` Ken Garlington 2001-04-09 13:54 ` Marin David Condic 2 siblings, 0 replies; 16+ messages in thread From: Larry Hazel @ 2001-04-07 13:41 UTC (permalink / raw) Mark Biggar wrote: > > tmoran@acm.org wrote: > > > > Anyone know where this came from? > > "In one infamous software error, a misplaced minus sign resulted in a > > fighter jet's control system flipping the aircraft on its back whenever > > it crossed the equator. " > > It was the fly-by-wire software for the F-16. Fortunately, > this error was caught in simulation and no planes were actually > flipped. For more info, you might want to look in the risks-digest > report database "http://catless.ncl.ac.uk/Risks". The bug in question > can be found easly by searching on "equator". > > -- > Mark Biggar > mark.a.biggar@home.com And some errors like this are just simulator related. Someone had a sign wrong on the F4J simulator and every time the pilot stepped on the brakes while rolling, the plane sped up. Made landings difficult but wasn't very difficult to find the problem. Larry ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-07 13:16 ` Mark Biggar 2001-04-07 13:41 ` Larry Hazel @ 2001-04-07 21:55 ` Ken Garlington 2001-04-09 13:54 ` Marin David Condic 2 siblings, 0 replies; 16+ messages in thread From: Ken Garlington @ 2001-04-07 21:55 UTC (permalink / raw) "Mark Biggar" <mark.a.biggar@home.com> wrote in message news:3ACF132F.95DD191A@home.com... : tmoran@acm.org wrote: : > : > Anyone know where this came from? : > "In one infamous software error, a misplaced minus sign resulted in a : > fighter jet's control system flipping the aircraft on its back whenever : > it crossed the equator. " : : It was the fly-by-wire software for the F-16. Actually, this isn't correct. It was an error in the simulation system, not the "fly-by-wire" embedded software. : Fortunately, : this error was caught in simulation and no planes were actually : flipped. For more info, you might want to look in the risks-digest : report database "http://catless.ncl.ac.uk/Risks". The bug in question : can be found easly by searching on "equator". : : -- : Mark Biggar : mark.a.biggar@home.com ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-07 13:16 ` Mark Biggar 2001-04-07 13:41 ` Larry Hazel 2001-04-07 21:55 ` Ken Garlington @ 2001-04-09 13:54 ` Marin David Condic 2 siblings, 0 replies; 16+ messages in thread From: Marin David Condic @ 2001-04-09 13:54 UTC (permalink / raw) I recall hearing of a jet engine simulation that had a similar bug with respect to burner temperature. Apparently, the temperature could go negative and since the scale was WRT absolute zero, air started sucking in from the back of the engine. Naturally, this is physically impossible - but the math for the simulation worked out that way. Given that it was, in fact, a simulation, the error didn't hurt anything, but it is an example of how easy it is for a minor mistake to totally botch up a system. (Something that might have been detected more readily with strong type checking and proper use of types/ranges.) There are similar stories of numeric calculations which "rolled over" mathematically causing the software to attempt to instantly reverse mechanical actuators. This is what is known in the technical jargon as "A Bad Thing". (Like crossing the streams! :-) A lot of these errors can easily be caught with range checks, but before beating up on the poor Fortran programmers who did this, remember that a range check alone won't necessarily save the day. You have to consider the speed of the software to determine if it can withstand range checking and you have to consider what your FDA strategy is going to be. A bad FDA strategy (or none at all) can be just as bad - or worse - than flipping sign bits arbitrarily. MDC -- Marin David Condic Senior Software Engineer Pace Micro Technology Americas www.pacemicro.com Enabling the digital revolution e-Mail: marin.condic@pacemicro.com Web: http://www.mcondic.com/ "Mark Biggar" <mark.a.biggar@home.com> wrote in message news:3ACF132F.95DD191A@home.com... > It was the fly-by-wire software for the F-16. Fortunately, > this error was caught in simulation and no planes were actually > flipped. For more info, you might want to look in the risks-digest > report database "http://catless.ncl.ac.uk/Risks". The bug in question > can be found easly by searching on "equator". ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-07 5:44 software failure question tmoran 2001-04-07 10:22 ` chris.danx 2001-04-07 13:16 ` Mark Biggar @ 2001-04-07 13:52 ` Ken Garlington 2001-04-09 18:13 ` Phaedrus 3 siblings, 0 replies; 16+ messages in thread From: Ken Garlington @ 2001-04-07 13:52 UTC (permalink / raw) I think this is the urban legend related to the F-16. As best as I have been able to reconstruct events, this did not happen in an F-16 in flight, but in a ground-based F-16 flight *simulator*. Apparently, only the northern hemisphere was programmed correctly into the simulation; when the pilot crossed the equator, the sudden transition in reference coordinates caused the simulation to show the pilot as inverted. You might check the RISKS digest at http://catless.ncl.ac.uk/Risks/18.94.html#subj14.1 for more information. (Note that there's some second-hand, obsolete, and just plain wrong junk about the F-16 in RISKS as well, so reader beware.) <tmoran@acm.org> wrote in message news:9Pxz6.992$ix4.198187@news1.rdc1.sfba.home.com... : Anyone know where this came from? : "In one infamous software error, a misplaced minus sign resulted in a : fighter jet's control system flipping the aircraft on its back whenever : it crossed the equator. " : http://www.newscientist.com/dailynews/news.jsp?id=ns9999595 ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-07 5:44 software failure question tmoran ` (2 preceding siblings ...) 2001-04-07 13:52 ` Ken Garlington @ 2001-04-09 18:13 ` Phaedrus 2001-04-09 20:57 ` Ted Dennison 3 siblings, 1 reply; 16+ messages in thread From: Phaedrus @ 2001-04-09 18:13 UTC (permalink / raw) I'm reminded of another famous software failure, that may or may not be an urban legend: According to the story, when programming a helicopter simulation for the Australian military, someone noticed that they didn't have any kangaroos. Rather than write a whole bunch of new code to simulate them, they just derived a new subclass from the class that they used to simulate the ground troops. When they flew the new version of the simulation, the kangaroos scattered just as expected when the helicopter flew over the hill. But imagine their surprise when the 'roos came back and started firing at the chopper with surface-to-air missiles! Phaedrus <tmoran@acm.org> wrote in message news:9Pxz6.992$ix4.198187@news1.rdc1.sfba.home.com... > Anyone know where this came from? > "In one infamous software error, a misplaced minus sign resulted in a > fighter jet's control system flipping the aircraft on its back whenever > it crossed the equator. " > http://www.newscientist.com/dailynews/news.jsp?id=ns9999595 ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-09 18:13 ` Phaedrus @ 2001-04-09 20:57 ` Ted Dennison 2001-04-10 1:38 ` Phaedrus 2001-04-10 15:39 ` Ted Dennison 0 siblings, 2 replies; 16+ messages in thread From: Ted Dennison @ 2001-04-09 20:57 UTC (permalink / raw) In article <4ZmA6.1693$Ak1.181271@newsread2.prod.itd.earthlink.net>, Phaedrus says... > >I'm reminded of another famous software failure, that may or >may not be an urban legend: >According to the story, when programming a helicopter simulation >for the Australian military, someone noticed that they didn't have >any kangaroos. Rather than write a whole bunch of new code to >simulate them, they just derived a new subclass from the class that >they used to simulate the ground troops. >When they flew the new version of the simulation, the kangaroos >scattered just as expected when the helicopter flew over the hill. >But imagine their surprise when the 'roos came back and started >firing at the chopper with surface-to-air missiles! I did some investigation on that one when it first made the rounds a couple of years ago. Apparently its mostly true, except that they also didn't have a model for the SAMs, so it used the default model, which was multicolored beach-balls. :-) --- T.E.D. homepage - http://www.telepath.com/dennison/Ted/TED.html home email - mailto:dennison@telepath.com ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-09 20:57 ` Ted Dennison @ 2001-04-10 1:38 ` Phaedrus 2001-04-10 15:39 ` Ted Dennison 1 sibling, 0 replies; 16+ messages in thread From: Phaedrus @ 2001-04-10 1:38 UTC (permalink / raw) The only thing worse than a bunch of kangaroos firing SAMs at your helicopter is a bunch of kangaroos throwing their balls at your chopper. ;-) Phaedrus "Ted Dennison" <dennison@telepath.com> wrote in message news:YmpA6.1157$FY5.85643@www.newsranger.com... > In article <4ZmA6.1693$Ak1.181271@newsread2.prod.itd.earthlink.net>, Phaedrus > says... > > > >I'm reminded of another famous software failure, that may or > >may not be an urban legend: > >According to the story, when programming a helicopter simulation > >for the Australian military, someone noticed that they didn't have > >any kangaroos. Rather than write a whole bunch of new code to > >simulate them, they just derived a new subclass from the class that > >they used to simulate the ground troops. > >When they flew the new version of the simulation, the kangaroos > >scattered just as expected when the helicopter flew over the hill. > >But imagine their surprise when the 'roos came back and started > >firing at the chopper with surface-to-air missiles! > > I did some investigation on that one when it first made the rounds a couple of > years ago. Apparently its mostly true, except that they also didn't have a model > for the SAMs, so it used the default model, which was multicolored beach-balls. > :-) > > --- > T.E.D. homepage - http://www.telepath.com/dennison/Ted/TED.html > home email - mailto:dennison@telepath.com > ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-09 20:57 ` Ted Dennison 2001-04-10 1:38 ` Phaedrus @ 2001-04-10 15:39 ` Ted Dennison 2001-04-11 12:12 ` Colin Paul Gloster 1 sibling, 1 reply; 16+ messages in thread From: Ted Dennison @ 2001-04-10 15:39 UTC (permalink / raw) >In article <4ZmA6.1693$Ak1.181271@newsread2.prod.itd.earthlink.net>, Phaedrus >says... >> >>I'm reminded of another famous software failure, that may or >>may not be an urban legend: >>According to the story, when programming a helicopter simulation >>for the Australian military, someone noticed that they didn't have >>any kangaroos. Rather than write a whole bunch of new code to >>simulate them, they just derived a new subclass from the class that >>they used to simulate the ground troops. I forgot about this part. The OO mumbo-jumbo that got thrown in here was just made up. They were interfacing their virtual sim to another simulation capable of generating and controlling other entities (perhaps MODSAF). When this is done, each entity MODSAF is controlling needs to be mapped on the virtual sim to an entity that the virtual sim's image generator knows how to render. Its fairly common in such a setup to map one entity to another similar one that MODSAF (or whatever they are using) doesn't have. I've been on two different projects that did this. There's nothing particularly OO about it. But the story has slowly mutated itself into some kind of unspecified object lesson on the dangers of OO programming. Go figure. To put my previous post in perspective, they weren't expecting SAMs to come out of MODSAF, so they didn't set up a mapping for them. That meant they got the default mapping, which happened to be multicolored beach balls. :-) BTW: I've personally seen a (simulated) marine helocopter fly in close formation with a heap of rubble for over thirty minutes due to a similar issue. We had them keep flying that long so we could monitor the network traffic and try to figure out where the bug was. The pilots entertained themselves during this time by pretending that the squarish rubble heap was a Borg ship. :-) --- T.E.D. homepage - http://www.telepath.com/dennison/Ted/TED.html home email - mailto:dennison@telepath.com ^ permalink raw reply [flat|nested] 16+ messages in thread
* Re: software failure question 2001-04-10 15:39 ` Ted Dennison @ 2001-04-11 12:12 ` Colin Paul Gloster 0 siblings, 0 replies; 16+ messages in thread From: Colin Paul Gloster @ 2001-04-11 12:12 UTC (permalink / raw) It was widely reported in Spring or Summer of the year 2000. I believe that the first time I heard about the beachballs is today. I had heard that they actually fired (in at least one report Stinger) missiles (well, technically beach balls can be missiles too). Apparently it did have basis in truth but a surprisng ommission from the commonly circulated urban legend as repeated earlier in the thread is that " [..]The head of the Defense Science & Technology Organization's LandOperations/Simulation division reportedly instructed developers to model the local marsupials' movements and reactions to helicopters. [..] Eager to demonstrate their flying skills for some visiting American pilots, the hotshot Aussies "buzzed" the virtual kangaroos in low flight during a simulation. The kangaroos scattered, as predicted, and the visiting Americans nodded appreciatively....[..] and the Yanks left with a newfound respect for Australian wildlife. Simulator supervisors report that pilots from that point onward have strictly avoided kangaroos, just as they were meant to." This demonstration in front of foreign officials is alleged to be the untrue noise making the reports inaccurate. A URL I had in July 2000 with a statement from a staff member at the department concerned pointed out that one would expect reporters to actually ring them up to confirm that the story is true. The URL pointed to a subdirectory of ~glen on HTTP://WWW.QNX.com but Glen seems to have left and it is not up there now. Colin Paul In article <XOFA6.2036$FY5.145687@www.newsranger.com>, Ted Dennison wrote: ">In article <4ZmA6.1693$Ak1.181271@newsread2.prod.itd.earthlink.net>, Phaedrus >says... >> >>I'm reminded of another famous software failure, that may or >>may not be an urban legend: >>According to the story, when programming a helicopter simulation >>for the Australian military, someone noticed that they didn't have >>any kangaroos. Rather than write a whole bunch of new code to >>simulate them, they just derived a new subclass from the class that >>they used to simulate the ground troops. I forgot about this part. The OO mumbo-jumbo that got thrown in here was just made up. They were interfacing their virtual sim to another simulation capable of generating and controlling other entities (perhaps MODSAF). When this is done, each entity MODSAF is controlling needs to be mapped on the virtual sim to an entity that the virtual sim's image generator knows how to render. Its fairly common in such a setup to map one entity to another similar one that MODSAF (or whatever they are using) doesn't have. I've been on two different projects that did this. There's nothing particularly OO about it. But the story has slowly mutated itself into some kind of unspecified object lesson on the dangers of OO programming. Go figure. To put my previous post in perspective, they weren't expecting SAMs to come out of MODSAF, so they didn't set up a mapping for them. That meant they got the default mapping, which happened to be multicolored beach balls. :-) BTW: I've personally seen a (simulated) marine helocopter fly in close formation with a heap of rubble for over thirty minutes due to a similar issue. We had them keep flying that long so we could monitor the network traffic and try to figure out where the bug was. The pilots entertained themselves during this time by pretending that the squarish rubble heap was a Borg ship. :-)" ^ permalink raw reply [flat|nested] 16+ messages in thread
end of thread, other threads:[~2001-04-11 12:12 UTC | newest] Thread overview: 16+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2001-04-07 5:44 software failure question tmoran 2001-04-07 10:22 ` chris.danx 2001-04-07 10:28 ` chris.danx 2001-04-09 15:24 ` Smark 2001-04-10 13:31 ` Marin David Condic 2001-04-10 16:01 ` Smark 2001-04-07 13:16 ` Mark Biggar 2001-04-07 13:41 ` Larry Hazel 2001-04-07 21:55 ` Ken Garlington 2001-04-09 13:54 ` Marin David Condic 2001-04-07 13:52 ` Ken Garlington 2001-04-09 18:13 ` Phaedrus 2001-04-09 20:57 ` Ted Dennison 2001-04-10 1:38 ` Phaedrus 2001-04-10 15:39 ` Ted Dennison 2001-04-11 12:12 ` Colin Paul Gloster
This is a public inbox, see mirroring instructions for how to clone and mirror all data and code used for this inbox