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Comment by ChrisMarshallNY | Hacker News Reader

I never got the chance to fly in a Dreamliner, but I have been told that its air is also more humid than standard jets (because of the carbon-fiber construction, I think, so metal oxidation isn’t an issue).

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> because of the carbon-fiber construction

yes

> so metal oxidation isn’t an issue

no. It's not rust, but that higher pressure air can hold more water at the same relative humidity. The higher pressure air is achievable because carbon fiber has higher tensile strength per weight.

That makes more sense.

Thanks!

> higher pressure air can hold more water at the same relative humidity

The 787 and A350 cabins have higher relative humidity.

> no. It's not rust,

Citation needed. Corrosion resistance is one of the most advertised benefits of the composite materials in those aircraft[1][2].

1: http://www.lb.boeing.com/commercial/aeromagazine/articles/qt...

2: https://skybrary.aero/sites/default/files/bookshelf/3851.pdf

Nice, then finally I won't get nosebleeds on long flights <3

Also, I get headaches on planes. The 10,000-foot altitude air pressure does it.

Really, it's that low on a regular plane? I thought it was more like 6000ft equivalent or so. 10k is high, it's like a third of the altitude they actually fly at.

Edit: it's between 6000 and 8000: https://aviation.stackexchange.com/questions/66563/why-arent...

So around 8000 for the likes of the bog standard 737 and A320 and around 6000 for the cool new carbon fibre ones I guess.

May be right. I was told 10K, but that was probably a number that was rectally-sourced.

10k is the altitude above which oxygen masks are required, and any decompression above this altitude triggers the oxygen masks to drop and pilots to make an emergency decent back down to 10k ft.

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