What specs do flight computers have?

[LambOfGod]

Hey, I'm interested in what type of computers aircraft companies use. i.e Boeing, Airbus, Lockheed etc..

I have some Q's - And is anyone here an aircraft computer designer or something along the lines?


What processors do they have?
RAM?
Who build them? (Microsoft, that would excite me:))
How much?I know they're a hell of alot better than all the mostly pos computers out there.

And I searched, I could only find post's critising FBW and A'bus.

Thankyou gentleman.

[VinRouge]

The most powerful computer on a modern passenger airline is the in flight entertainment system. Seriously.

Aircraft FMCs, FADECs and electronic flight control systems are not performance systems, at all. Clock speeds in comparison to modern microprocessors are Slooow, and there isnt particularly much RAM. Note, there are rarely Hard disk drives, as unless they are sealed, typically fail above 20,000' as the read head relies on an air gap to avoid contacting the disc.

Microsoft? I take it you dont work with Aircraft. The 'operating systems' consist of multiple redundancy lines of code that are optimised for reliability and we dont use any recognisable operating system on modern aircraft. For example, all a FADEC does is map parameters to a fuel flow and inlet guide vanes; it is not required to send email!

[jhurditch]

Nothing to do with Microsoft as far as I know. Honeywell is a large supplier for boeing on the 777's.
As for specs not sure however they are a VERY stable system. Older FMC's on the 747 types have very momentary lag when processing/loading route data.

[Graybeard]

Marketing life on consumer products is on the order of six months before a there's a "new, improved" model. Avionics, including microprocessor based systems, must have a much longer life, both in durability, and in availability of replacement components. There are 50 year old Arinc avionics boxes still in revenue service, and 30+ year old boxes with microprocessors.

Avionics manufacturers will make last time buys for parts that will be obsoleted within the expected life of their unit: production life plus at least seven years. If their design uses state of the art electronics today, they will have to predict how many of these boxes they will sell into the far future, and the failure rate, then make a last time buy before the new box is even certified. This is just part of the reason for high prices of avionics.

The choice of Custom vs. COTS, Commercial Off The Shelf software, depends at least partially on the criticality of the application. Cat IIIc Autoland sensors and fright guidance systems get the greatest safety scrutiny, of course. The EFB, Electronic FlightBag, typically uses COTS, with some customized software.

GB

[thonislim]

Hi,

I guess you're talking about EFB here. Do a google search on EFB and you will find out which airline uses which EFB.

What processors do they have?
RAM?
> depends. class 1, 2, 3 have dif specs & even amongst dif brands there's differences. Specs is not the only concern here, usability and intuitiveness, how much back-office ops work it can do, etc

Who build them? (Microsoft, that would excite me)
> Boeing has more than 90% market share through the company it controls, jeppesen

How much?
> can be really expensive or dirt cheap

[CaptainSandL]

For the 737:

The latest FMC – Model 2907C1, has a Motorola 68040 processor running at 60MHz (30Mhz bus clock speed), with 4Mb static RAM and 32Mb for program & database.

From Flight Management Computer (http://www.b737.org.uk/fmc.htm)

[Ezy.Pilot]

as far as I know, but I am happy to stand corrected here, is that there a mix of computers on the A320. Some analogue, some digital. Some with a Intel 80186 CPU, some with a Motorola 86010.

Reason for this is that software engineers get a "spec" and design an output for a given set of input parameters. How they do it is the black box in the middle and because the hardware platforms used differ from each other, no bug can replicate itself on the other computers. Fault tolerance.

I hope that the CPU's used are radiation hardened, made using >1μm lithography and made resistant against voltage spikes and the like.

If there is an on-board OS, which I doubt, then it's probably an embedded real-time OS with ab-so-lu-te-ly not no resemblance to anything coming out of Redmond. I don't think even Bill Gates would want his IC hart monitor to run Windows...

EFB's usually run either Linux or Windows and IFE systems are the hard core CPU and RAM users.

[dusk2dawn]

RTOS, Embedded real-time OS, software development toolkits, embedded c compilers, IDE, debugger, hardware probes, hypervisor - Green Hills Software (http://www.ghs.com/products.html)

Green Hills Software’s Operating System Selected for Boeing 787 Flight Control Electronics

Santa Barbara, CA—July 6, 2005—Green Hills Software, Inc., the technology leader in operating systems and development tools for safe and secure systems, announced today that it has been selected by Honeywell International to supply the operating system and development tools for the flight control electronics Honeywell is developing for the new Boeing 787 aircraft (formerly known as the 7E7).

“Green Hills Software is pleased that Honeywell has selected our INTEGRITY 178B operating system to meet the demanding reliability and safety requirements of their new flight control system for Boeing’s 787 Dreamliner,” said Dan O’Dowd, founder and chief executive officer of Green Hills Software. “INTEGRITY 178B is a proven solution that has enabled many avionics manufacturers to meet their safety-critical software requirements on time.”

Green Hills Software’s INTEGRITY-178B operating system was designed from the ground up to meet the demanding safety and performance requirements of flight-critical systems. INTEGRITY-178B complies with the aviation industry standard ARINC 653-1 applications software interface and has been used in numerous systems certified to the most stringent avionics software safety standard, RTCA/DO-178B Level A. Green Hills Software’s in-house engineering staff is responsible for the development and DO-178B compliance of INTEGRITY-178B and is also available to assist customers in certifying their applications.

[TinyTim2]

The important fact is not the speed of the processor nor the ram but what the system needs . If the system only has four or five calculations to make per sec does it need the power to do ten thousand ? No and more importantly it will be reliable if it is simpler , so yes most ac computers are very slow by modern standards but they are a thousand times more reliable and that is the most important fact

[kijangnim]

Greetings
What matters most is, does the selected CPU have hidden secrets? and is the obsolescence manageable?

Most of companies develop their own motherboards around the selected CPU , along the basic operating software, and finally the application.

For the applications,most companies use ADA object oriented language (linux), which is now a standard set by the airframers.

Software and Hardware have to be DO 178B compliant, with the appropriate level (A,B,C,D)
I do agree that today IFE is the most advanced.:ok:

I think that an interresting debate would be:
Since there is now a moduler Avionics concept, basically made of mother board on which applications a runing ( instead of recievers...)
would not it be very attempting to develop the software in India, and the Hardware in China for price consideration :eek:

[chris.dever]

SLF on a long flight 5 hours out of AKL into LAX at FL3x0 on a 777 - the Entertainment Computer did a very noisy reboot with the restart dialog streaming through all the screens onboard.

I remember thinking at the time - "F%$#^..... hope this is isolated to the Entertainment system !!"

[18-Wheeler]

AFAIK the Honeywell FMS's use a CPU that is either an Intel 386 or one much like it - Don't quote me on that though.

[Dan Winterland]

Depends on the model. I was told the 747-400 ran off an Intel 8086 - which is why it's so slow. It's stuck with this processer as it's what it's certified with. When I flew the thing, we had some newer models whichhad faster FMCs as the RAM had been increased. But a CPU change required re-certification.

[bjornhall]

Just curious: How much of the system logic on a modern airliner is implemented as software running on processors, and how much is implemented directly in hardware using ASICs, FPGAs or CPLDs?

[LambOfGod]

Ok, well now I have an idea:ok:

But I would have thought something that is FBW would need a fast processor. Say an A380, wouldn't it be doing a few more calculations that a few a seccond. Or does everything have its own CPU?

[bobcat4]

VinRouge:

Microsoft? I take it you dont work with Aircraft. The 'operating systems' consist of multiple redundancy lines of code that are optimised for reliability and we dont use any recognisable operating system on modern aircraft. For example, all a FADEC does is map parameters to a fuel flow and inlet guide vanes; it is not required to send email!

As far as there anything like an OS, I would put my money on VxWorks. NASA used (are using it now?) it on Mars. Very reliable. I think both Boeing and Airbus have VxWorks running in some of the computers in their aircraft fleet.

Bob.

[bobcat4]

TinyTim2 wrote:

The important fact is not the speed of the processor nor the ram but what the system needs . If the system only has four or five calculations to make per sec does it need the power to do ten thousand ? No and more importantly it will be reliable if it is simpler , so yes most ac computers are very slow by modern standards but they are a thousand times more reliable and that is the most important fact

Right! Take a look at the Space Shuttle. Its avionic computer is a 32-bits IBM Model AP-101. Five actually. Redundancy is important to NASA.

I have not been able to find specs on the computer, but here are some links:

Space Shuttle - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Space_shuttle)
IBM AP-101 - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/IBM_AP-101)
HSF - The Shuttle (http://spaceflight.nasa.gov/shuttle/reference/shutref/orbiter/avionics/dps/gpc.html)

It's probably slower than your iPod, but it does the job. And I guess playing Solitaire on the avionics is not needed. When it does the job and it's working, leave it like that.

Bob.

[fc101]

A quick reply from a software engineer friend:

For programming these systems take a look at the ADA and SparkADA programming languages.

Furthermore the specifications of such systems might (will) be split across more than one team without direct contact and using different sets of tools, software and hardware.

Microsoft and the rest of the known manufacturers do not even come into the picture and don't produce software, hardware etc for these kinds of environments.

Also the IFE systems are completely separated from the avionics side of things. If the IFE crashes (they mostly run off-the-shelf systems based on Unix/Linux or Windows) then it doesn't matter.

If the avionics fail (and it really is quite hard to get an avionics system to fail) then failures are very much contained to specific parts of the system. Failure here doesn't necessarily imply failure of the whole system. There's also much emphasis on failure tolerance (ie: if one piece fails then there's a backup immediately available), voting systems etc. Also the tolerances for these systems are specified very tightly but implemented using extremely robust technologies.

A few good links to wikipedia will help:

Fault-tolerant system - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Fault-tolerant_system)
Avionics - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Avionics)
Integrated Modular Avionics - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Integrated_Modular_Avionics)
Avionics software - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Avionics_software)
http://en.wikipedia.org/wiki/SPARK_(programming_language)

Much reading there.

But if you're experience to computing is "Microsoft","Apple" and "Linux" then this area is way removed - you can forget everything about desktop computing.

fc101
E145 Drive

[hugel]

Crib sheet:

Embedded processors Moto 68020, 68040, Power PC common

Languages : Ada, Spark reduced instruction set Ada , and C

RTOS : VxWorks, Greenhills Integrity, Windriver
Partitioned secure memory areas (to ensure processes don't overwrite each other)

IDE: Apex, Rhapsody etc etc

Multiple redundant processing boards with processor level communications for synchronisation and redundancy

Board support packages often from vendor

In-house programmed custom logic common.

Database and low level drivers often bought-in

Operational Flight Program (application) written in-house

DoD178B for software and 254 for hardware are the considerations.

Trend to standardised databus such as AFDX(Airbus), and standardised digital video (such as ARINC888) and standardised hardware often attempted (Integrated Modular Avionics)

hugel

[kijangnim]

Greetings,
On the Pegasus Airbus FMS2, HWL is using an AMD 29050 Risc Processor, in fact this processor was obsolete when they bought it, the plan was to overclock/improve this processor.

[MMEMatty]

Was once in the front right seat of a CRJ when the PFD/ND/EICAS all went over to the "Blue Screen of Death" at about 4000' on the approach into BHX one afternoon... was hilarious!


(becase, you guessed it, we were in the sim!)

Matty