SpaceX performs static fire test on Falcon Heavy | Hacker News Reader

SpaceX performs static fire test on Falcon Heavy

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102 pointsLeonM31 comments

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Official SpaceX video: https://twitter.com/SpaceX/status/956236301275054080

Yes. In the Twitter video, skip the first 16 minutes. Then one minute of action.

Better video: https://www.youtube.com/watch?v=NuXHriwQB9g

https://twitter.com/elonmusk/status/956233892637286400 All good, launching in a week...

I wish I lived closer - I'd love to hear/feel this in person.

The feeling of top fuel dragsters coming off the line (https://youtu.be/W9L3bllEbm4?t=11) is intoxicating - I can only imagine what the Falcon Heavy would feel like!

Ha ha for irony! A drag-racing Tesla is pretty soundless off the line.

I live a couple miles down the river and it was rattling my windows.

Paddle boarding out to watch one of their launches should be a bucket list item for anyone living in Central Florida.

> "Five million pounds of thrust being held to the ground by SpaceX's systems"

So, what happens if those systems fail?

edit: nice, apparently I commented on Reddit today.

liftoff

or a cartwheel

Followed by rapid disassembly

making something stay on the ground is far less challenging than making something go to space

i think they've got this

Most of the thrust is simply to counter the weight of the rocket & fuel. The hold-down clamps only have to withstand a fraction of that.

SpaceX lists the Falcon Heavy as weighing 3,125,735 lbs (presumably that's the "wet" weight).

So, the hold down clamps 'only' need to deal with ~2,000,000 lbs of thrust. There are 6 clamps, IIRC, so that's 333k lbs each. Seems reasonable.

More good footage + audio: https://twitter.com/nova_road/status/956221490785026053

Some other footage:

https://www.youtube.com/watch?v=NuXHriwQB9g

https://www.youtube.com/watch?v=8ZZs1pxqB9c

How much stress is placed on the components for this test? Do they use a fully fueled rocket or is there only sufficient fuel to complete the burn?

Fully fueled, as that reduces the upward strain on the hold-down clamps.

Also: "Test like you fly."

Awesome. Really glad there was someone live streaming.

However, I wish the guy didn't yell into the microphone repeatedly over the sound of the firing. I understand there are going to be people nearby yelling, but if anyone can suppress the urge to yell at that moment, it should be the person running the livestream camera.

Anyway other than that, well done. Nice to have some commentary as well going along with it.

Engine ignition is around the 16 minute mark

Doesn't anybody edit their videos anymore?

This video is a Periscope livestream, so there wasn't an opportunity for editing.

A good example of why Periscope isn't a very useful idea.

Whoa thats a big exhaust. Hopefully someday we will see it go up. Saturn V launches were awesome.

Next week according to Musk.

At the very moment it is scheduled for Feb 6th.

>Next week...

..."or so" according to Musk.

"Or so" being an important phrase.

But why was it so short?

That was long. Static fires of Falcon 9 rockets at the Cape and VAFB are normally 3 seconds.

Ok, I guess "static fires" are not the same as "engine firing". I was expecting something like in this video: https://www.youtube.com/watch?v=976LHTpnZkY

That's a single engine on a test stand designed for full duration test fires (SpaceX also does full duration test fires of a complete booster (i.e. 9 engines)).

Launch pads are not test stands. They aren't designed to withstand the sustained thrust of a rocket being held down. SpaceX doesn't have a test stand capable of doing a full duration test fire of Falcon Heavy.

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