Hacker News Reader

Comment by MR4D | Hacker News Reader

The thought of lighting up 27 rocket engines in unison is absolutely crazy. Then again, SpaceX thrives on crazy ideas like reusing rockets, which are now the norm.

Good luck to them. Will be interesting to watch this beast launch!

View on HN

It's not exactly "unison" (it is indeed very tightly coordinated though). The engines will be lit in pairs, with a couple dozen milliseconds between each set starting up.

How on earth are all your answers so informative and authoritative? Do you work in the industry? SpaceX employee? Enthusiast?

Honestly; thank you for taking the time to spread the knowledge.

Just a passionate enthusiast with some friends in the industry.

Here's a source on the engines being started in pairs: https://www.nasaspaceflight.com/2017/11/spacex-aims-december...

Relevant quote from that link:

"Instead, Falcon Heavy will take a page from the Space Shuttle’s book and will employ a staggered start sequence – like main engine start on Shuttle where each main engine started 120 milliseconds after the previous.

For Falcon Heavy, it is understood that two engines will be lit simultaneously followed by the next two… and so on until all 27 are up and running."

Well, thanks very much. Go Falcon Heavy!

/r/SpaceX [0] is very very informative

[0] https://www.reddit.com/r/spacex/

It can be, but the moderation is very heavy handed... I don't tend to visit there much anymore.

That's why it's informative.

It's rarely the only (or even first) source of any particular piece of information, and with only a couple new posts a day from "approved" posters, there's just not enough there to warrant visiting often.

r/SpaceXLounge for the same people with less moderation

I read this thread much deeper than I normally would because of the interesting comments that user made, thanks indeed!

IIRC, the engines do not light up simultaneously, ignition is staggered.

Reply on news.ycombinator.com