Hacker News Reader

Comment by crispyambulance | Hacker News Reader

This is the first time, I think, we got to see the charred surface of the first stage. I wonder what kind of processing is involved to make the stage usable again?

Do they just put it through a car wash and re-fill for next time?

Is everything reusable on the first stage?

View on HN

We've certainly seen gunked up stages after landing -- and a lot of the gunk isn't charred paint (or thermal coating), but soot from the rocket exhaust in the re-entry burn, which they can just clean off.

Agreed. We've seen lots and lots of primary missions, but the truly revolutionary thing, the booster landing, we never followed this close.

Most of that is soot, not char (i.e. it's "dirt" that has stuck to the rocket, not the actual material on the outside of the rocket charring).

Anecdotal: I believe musk said that the charred outside was surprisingly only in need of a fresh coat of paint.

Wouldn't be surprised if it's similar to the coatings placed on the launch pad stabilizers. The paint is meant to char because it acts similar to a ceramic preventing damage to the underlying metal. There's a good youtube video of this on the moon launches where the tail fin hold downs char, but don't warp.

The grid fins have paint like that, which is why they catch on fire.

They're aluminium underneath the paint - and that also melts a bit on a high speed GTO reentry, hence the likely switch to titanium grid fins in the future.

In a funny way, i'd be happy if it got to a point where they just sent the dirty/charred rockets back up.

"It's a rocket - of course it's going to get dirty!"

Reply on news.ycombinator.com