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Comment by stavros | Hacker News Reader

If the displays are merged seamlessly, how will you know if one has failed?

I assume both displays in use, but have failover to one only if a display goes “dead”and then the single display can still display the most critical information/controls to the pilot; to me that seems like the only logical implementation. Giving 1 of the 2 screens failing. It should be fairly easy to set up a redundancy failover process, I’ve done that many times in embedded coding where we failed over to a backup system.

Reduction in brightness?

I assume they're using LCDs, where the brightness is provided by the backlight.

> I assume they're using LCDs, where the brightness is provided by the backlight.

Presumably that also would be duplicated. Why go to all the effort of having two displays but still have the risk of a single backlight going out and making both displays useless?

Uhh, the pilot will notice that the right half of your display is black and you have to move the displayed data to the left one?

Uhh, that's not "seamlessly blending two displays", that's just having two desplays. If you've seen photos of planes, they don't just have an empty screen next to a working one anywhere.

Ah, I misunderstood - it's not uncommon to have those "big" screens also put together from two different screens side by side.

This is actually what I meant by "merged together". They are two separate displays controlled by separate computers, with separate power supplies etc. During normal mode operation they're synchronized somehow and can draw a large image over the entire display area, but in emergency mode you can display crucial flight data on only one of them if the other stop working.

I have never really thought much about it, but I guess the actual LCD thingie is manufactured in one piece and the control signals just being split between different computers somehow, but I don't know anything about how these things are made! :)

Here's a paper on a redundant display for military aircraft. Each LCD panel has redundant inputs, driver circuits, and power supplies. The two displays are built on a single LCD substrate, so there is no line between the two. https://www.mrcy.com/resourcehub/displays/dual-redundant-dis... https://www.mrcy.com/legacy_assets/siteassets/product-datash...

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