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LeonM
Engine ignition is around the 16 minute mark
valuearb
Doesn't anybody edit their videos anymore?
Ajedi32
This video is a Periscope livestream, so there wasn't an opportunity for editing.
valuearb
A good example of why Periscope isn't a very useful idea.
coldcode
Whoa thats a big exhaust. Hopefully someday we will see it go up. Saturn V launches were awesome.
ChuckMcM
Next week according to Musk.
pseudometa
At the very moment it is scheduled for Feb 6th.
Robotbeat
>Next week...

..."or so" according to Musk.

"Or so" being an important phrase.

pavel_lishin
> "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.

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

i think they've got this

SAI_Peregrinus
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.
[deleted]
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JshWright
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.

Implicated
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!

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

simik
But why was it so short?
greglindahl
That was long. Static fires of Falcon 9 rockets at the Cape and VAFB are normally 3 seconds.
simik
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
JshWright
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.

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

Also: "Test like you fly."

natch
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.