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Comment by cptskippy | Hacker News Reader

> The fairings currently cost a total of $6MM for each launch

WHAAAAA?! What are they made of? I thought the fairings were just the covers for the payload. What makes them so expensive?

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They're large or larger than a double decker bus. They're released well after first stage separation so they need to be as light as possible. Stupidly light. Despite being very large and very light, they need to be very resistant to vibration through hypersonic speeds and go through a huge range of temperatures. They need to separate reliably and equalize pressure during ascent. They look like a mere shell, but they're actually advanced composite structures with a fair amount of tech involved.

They also have a built in parachute deployment mechanism which can safely get them down to sea level.

I don't think it's fair to count that as part of the 6M cost that you are "saving", if you just did the typical thing and threw them away you wouldn't need parachutes.

Carbon fiber and aluminum, mostly.

The reason for reuse isn't really the cost (though that's certainly part of it). The main driver is that they are going to become the production bottleneck if Falcon 9 reaches the flight cadence they are shooting for. The fairings are a big, unwieldy shape, and they take up a lot of room during the manufacturing process, so they can only make one at a time.

Elon described it in an interview once as this:

If you saw $6 million, falling from the sky, would you try to catch it? Each fairing is around $3 million, so they're trying to catch it. That gives them $6 million more per-customer they can discount the price should they need to get really competitive. It is really kind of insane that no one has tried this before.

Love that kind of commentary Elon provides.

Link to the interview?

I did look at the past few interviews I've watched, but can't easily find it and google is failing me. It was one of the long hour+ interviews, I do believe.

Musk has used the pallet of cash analogy several times.

Here is Musk using it in regards to saving the fairing @ ISS Research and Development Conference 2017:

https://www.youtube.com/watch?v=5cPMS6cT0Ig&t=825

In regards to the first stage (booster stage) at Code Conference 2016:

https://www.youtube.com/watch?v=wsixsRI-Sz4&t=545

They have to survive the launch through the thicker part of the atmosphere, yet still be light enough to not eat into the payload much.

Made from aluminium honeycomb and carbon fiber mostly, if I remember correctly. But those things are quite large as well.

I think they play a pretty important role in protecting the payload from atmospheric drag among other things, and it needs to be pretty strong / reliable. That must add to the cost. Don't know what materials are used so can't say about material costs.

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