Just curious. What do they use. Pentiums, Motorolas, specially made CPUs… what? What language is the OS?
It varies quite a bit. Usually not a pentium because of the heat generated. When I worked on avionic systems we designed one “brain” around a motorola 68030 (this was back in the early 90’s), and fancier radar and flir systems had their own custom brains which reflected the dedicated tasks they performed.
Operating systems also vary. Most of the “brains” are designed for some specific task and don’t really have an operating system. Their operating system is just the applications code that runs on them. It used to be that many of these “brains” couldn’t afford the overhead of a standard operating system, but as computers become more powerful, commerically available operating systems are becoming more popular in these types of uses. Don’t expect to find Windows running your 747 though. They are usually special embedded operating systems like VxWorks or custom versions of linux. Something that is only used to display data might contain an embedded version of windows.
Do aircraft use radiation-tolerant (“rad hard”) chips, or is that just for space? Last time I checked (about 2 years ago) the most powerful rad-hard CPUs were based on Motorola PowerPC 603 chips.
I don’t even dare to imagine that! The horror! A Blue Screen of Death could literally mean Death to all.
I can’t answer a definite ‘no’, but I know for sure that (some) non-hardened chips are used in some planes. I have worked with PowerPC based systems, running VxWorks and/or LynxOS, which are used in flight. (There was a project using Linux, but I’m not sure if it was intended to fly, or just ground support.) Normally it’s high-temperature versions of the chips, as it can be difficult to ensure proper ventilation, but otherwise it’s the same CPU as you can get in an Apple Powerbok.
Not only space. Also in particle physics! admittedly not much, but there are occasions when you need radiation hardened electronics in particle physics experiments. They have quite some experience in this at CERN.
There has been a fault in module LEFTENGINE.DLL. Abort, Retry, Fail?
I bet the crew of the USS Yorktown aren’t laughing. They had a highly-publicized SNAFU in 1997 when the Navy tried automating shipboard functions with Windows NT.
Although bashing Microsoft is fun, and sometimes appropriate, there was more to the Yorktown Incident than a simple “Windows is Bad” statement can account for. The systems were rushed into production without real simulation or testing, the crew wasn’t particularly trained for the software and the applications written on NT didn’t catch the mistake either.
One thing to keep in mind is that creating “man-rated” systems is neither easy or cheap. Preventing issues like the Yorktown means that you have to create reliable software and hardware that:
- Does exactly what you expect it to (including fail in a predictable fashion).
- Doesn’t do anything you don’t want it to do (no hidden features and no way to work around the exposed features).
- Can not be tampered with in a fashion that is undetectable (any change to code or hardware causes a “safe” system failure)
- Systems fail in a safe and reliable fashion (either rolling over to backups, or reverting to “neutral” settings if possible).
The space program has some of the best material on addressing these issues. Here is a link on the history of computers in the US space program.
I can’t find any of the standard Secure Software and Man Rated Software guidelines online at the moment, but I’ll keep looking.
Well, I know for a fact that the F-22 uses at least one Intel 80386.
I also heard that the Apache helicopter uses Intel i960 based processors.
As for rad hardened parts, usually they are not used. They are so expensive, it is easier to build shielding around the parts. 1/4 inch aluminum does the trick.