jnjnilson6

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I would be glad to know if anybody has any information about the processors employed in the cockpit of an airplane, controlling the gauges and input from the pilots (model, architecture, speed). And what about the processors in the systems embedded into the backs of seats on which passengers view movies and flight-related information for summary enjoyment?


I would gladly appreciate any answers pertinent.

Thank you!
 
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Here's a stackexchange for exactly this:

"How dissimilar are redundant flight control computers?"
"Each unit is composed of two dissimilar boards, one driving the output and the other checking it. Dissimilar means both different CPUs and chipsets (A320 uses i386 (Intel) and m68k (Motorola); newer models use different combinations, basically whatever was widely used at the time they were designed) and software written by two independent teams."


Why such ancient CPU? A 386???
Because of the looooong development timeline.
The A300 series started design in the 1960s. A320 variant in 1981.
You use what is...

USAFRet

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Looking around, the companies are pretty cagey with exactly what processor is in their systems.

But it is NOT an off the shelf consumer CPU.

For instance:
"NXP has also been at the forefront of avionics migration from federated avionics systems built on single core processors to Integrated Modular Avionics (IMA) built on multicore SoCs."


Example at Garmin:

"Powerful dual-core processors boost the system’s graphical display capabilities"


But these devices do not need a lot of brainpower.
Consider a non-aviation standalone GPS. Under $100.
Yet can connect to multiple GPS sats, hold the entire road system of the USA, update location and speed in near real time, with multiple voice text to speech.

Why do aviation electronics cost so much?
Zero defect code, certification, and scale. If you're only selling 1,000 of a particular model, price goes up a lot.
 
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USAFRet

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Here's a stackexchange for exactly this:

"How dissimilar are redundant flight control computers?"
"Each unit is composed of two dissimilar boards, one driving the output and the other checking it. Dissimilar means both different CPUs and chipsets (A320 uses i386 (Intel) and m68k (Motorola); newer models use different combinations, basically whatever was widely used at the time they were designed) and software written by two independent teams."


Why such ancient CPU? A 386???
Because of the looooong development timeline.
The A300 series started design in the 1960s. A320 variant in 1981.
You use what is available at the time.

It would be conterproductive to want to use the latest and greatest. The whole thing is designed around the capabilities of the chips at the time.
A new one requires all new code, and astoundingly expensive certification.


Even the ubercool new A380 has computer patents going back to 2006. So nothing newer than that.
 
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USAFRet

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i wonder if the older CPUs with vintage components and 1000 nm (!) process helps for mitigating interferences, solar particles, etc...

Also Intel has stopped i386 production in 2007 so Airbus has probably changed the model used. Or maybe they have a big inventory lol
(source : https://en.wikipedia.org/wiki/I386 )
For the A380, something newer.

For the hundreds of A320 in the air....i386 era.
But also, there are dozens of "CPU" or SoC in a typical airliner.
Flight controls, nav, etc, etc, etc.

No single CPU involved.
 
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I would be glad to know if anybody has any information about the processors employed in the cockpit of an airplane, controlling the gauges and input from the pilots (model, architecture, speed). And what about the processors in the systems embedded into the backs of seats on which passengers view movies and flight-related information for summary enjoyment?


I would gladly appreciate any answers pertinent.

Thank you!
While I won't say which airplane this was, I can tell you I worked on a flight control system where the CPU was a PowerPC 750 based part. The company was moving onto an ARM based platform since nobody makes PowerPC parts anymore.

The processors in the in-flight entertainment systems are likely some variant of an ARM Cortex-A CPU.
 
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i wonder if the older CPUs with vintage components and 1000 nm (!) process helps for mitigating interferences, solar particles, etc...
As I understand it, it is part of the design considerations for preparing a radiation hardened part for aerospace applications.
Also Intel has stopped i386 production in 2007 so Airbus has probably changed the model used. Or maybe they have a big inventory lol
(source : https://en.wikipedia.org/wiki/I386 )
Obsolescence management is a serious problem in electronics and there are trade publications to assist with the process. It's customary, when faced with impending obsolescence of such hardware, for program managers of all affected next-level assemblies to be notified. There are several possible outcomes including lifetime buys to support forecastable future production. They can re-design to use a newer/substitute component but that can be costly if it requires complete requalification of the assembly.

And then they can, of course, obsolete their product in favor of an all-new design but there remains the issue of fielded systems for which they'll still likely make a lifetime buy to support with spares and repairs.

If left to guess I could imagine Airbus doing a combination of redesign, new assembly design (for newer aircraft models), redesigns for customers that want to buy updated units with form/fit/function compatibility for their fielded fleets, and lifetime buys to support the fielded fleet for operators that don't want either. Of course, exactly what they did depends on what the operators wanted and willing to pay for.
 
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kanewolf

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As I understand it, it is part of the design considerations for preparing a radiation hardened part for aerospace applications.

Obsolescence management is a serious problem in electronics and there are trade publications to assist with the process. It's customary, when faced with impending obsolescence of such hardware, for program managers of all affected next-level assemblies to be notified. There are several possible outcomes including lifetime buys to support forecastable future production. They can re-design to use a newer/substitute component but that can be costly if it requires complete requalification of the assembly.

And then they can, of course, obsolete their product in favor of an all-new design but there remains the issue of fielded systems for which they'll still likely make a lifetime buy to support with spares and repairs.

If left to guess I could imagine Airbus doing a combination of redesign, new assembly design (for newer aircraft models), redesigns for customers that want to buy updated units with form/fit/function compatibility for their fielded fleets, and lifetime buys to support the fielded fleet for operators that don't want either. Of course, exactly what they did depends on what the operators wanted and willing to pay for.
There is also the possibility of salvaged parts. Look at Davis Monthan AFB. USAF keeps acres of salvageable spares.
 
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Eximo

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When my brother worked in aviation they often came up against strict FAA guidelines. Like not even being able to replace a 7 segment display with another color since it wasn't certified. Even though that particular display was out of production and unavailable.

We used to go to electronics swap meets and his company would send along a list of things he was to buy immediately if spotted. Mostly radios and instrument clusters.

There will also be companies out there that specialize in plug in certified products as replacements/spares. The extreme costs of airplane parts come with all the certification headaches and developments.
 
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There is also the possibility of salvaged parts. Look at Davis Monthan AFB. USAF keeps acres of salvageable spares.
Absolutely. And Davis Monthan pro-actively pulls, condition tags, packages and stocks many (if not most) avionic sub-assemblies from the boneyard aircraft so they are both properly preserved and readily available to the supply system. Those serialized items were included in the "fielded fleet" calculations they did for MR & O projections by the program office at the company I worked for.
 
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USAFRet

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