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Falcon Heavy Launch [video]

spacex.com

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Re: Falcon Heavy Launch [video]

#11

Post by numpad0 »

Klathmon wrote: post #3

One really cool thing I heard in this video, is the double sonic booms from each booster. There are reasons behind it that I don't really understand, but each booster makes 2 distinct sonic booms as it comes in to land. With Falcon Heavy launches, it makes a total of 4 of them!

I don’t understand either, but read that supersonic objects generate shockwaves at nose, root of wings(if any), and tail. Shockwaves also may reflect off terrains.

Possibly it should always be “BAbababang-baaaang…”, and the first three might be either indistinguishable or ones after the first are too weak, except it becomes noticeably apart on extremely long objects like F9?

1: https://www.nasa.gov/centers/armstrong/multimedia/imagegalle...

Re: Falcon Heavy Launch [video]

#12

Post by dotnet00 »

chasd00 wrote: post #2

The couple seconds of tracking camera footage of the boosters coming back down looked amazing. I wish it wasn't so foggy at the pad! When the second stage separates there's a few cables that are flying around. Does anyone know what those are used for? Electrical connections between the stages maybe?

I'm guessing you're referring to the stiffener that helps the second stage engine's nozzle hold its shape?

Re: Falcon Heavy Launch [video]

#13

Post by MontagFTB »

Klathmon wrote: post #3

One really cool thing I heard in this video, is the double sonic booms from each booster. There are reasons behind it that I don't really understand, but each booster makes 2 distinct sonic booms as it comes in to land. With Falcon Heavy launches, it makes a total of 4 of them!

SmarterEveryDay has a great video explaining this audio phenomenon from a previous Falcon Heavy launch: https://youtube.com/watch?v=ImoQqNyRL8Y

Re: Falcon Heavy Launch [video]

#15

Post by usrusr »

Now that Falcon 9 landings have become so routine, it feels surprisingly wasteful to see that mission profile with the center booster burning up without even trying.

I wanted to write something about that lack of center booster reuse on falcon heavy feeling irrationally worse than a single F9 launch in the non-reusable profile (for a slightly higher payload iirc), but then I discovered that the non-reusable F9 profile hasn't happened in quite a while. Nice! When they started with the reuse, I was expecting the full payload profile to be a far more regular occurrence. (even if in hindsight I see that none of my reasons for that expectation make any sense)

Re: Falcon Heavy Launch [video]

#16

Post by wiredfool »

usrusr wrote: post #15

Now that Falcon 9 landings have become so routine, it feels surprisingly wasteful to see that mission profile with the center booster burning up without even trying. I wanted to write something about that lack of center booster reuse on falcon heavy feeling irrationally worse than a single F9 launch in the non-reusable profile (for a slightly higher payload iirc), but then I discovered that the non-reusable F9 profil…

Edit: Units... I'd be the one going in mph through the surface of mars.

~The booster was going 12km/sec at MECO, which is more than escape velocity. What they're doing with the second boost, they're not telling anyone.~

Re: Falcon Heavy Launch [video]

#17

Post by BitwiseFool »

usrusr wrote: post #15

Now that Falcon 9 landings have become so routine, it feels surprisingly wasteful to see that mission profile with the center booster burning up without even trying. I wanted to write something about that lack of center booster reuse on falcon heavy feeling irrationally worse than a single F9 launch in the non-reusable profile (for a slightly higher payload iirc), but then I discovered that the non-reusable F9 profil…

>"wasteful to see that mission profile with the center booster burning up without even trying."

My understanding was that the intended orbit / mission profile means that they must fly the center core in expendable mode. Otherwise, the satellite wouldn't be able to reach the intended orbit with the intended amount of fuel for the mission's duration.

Re: Falcon Heavy Launch [video]

#18

Post by mercurywells »

usrusr wrote: post #15

Now that Falcon 9 landings have become so routine, it feels surprisingly wasteful to see that mission profile with the center booster burning up without even trying. I wanted to write something about that lack of center booster reuse on falcon heavy feeling irrationally worse than a single F9 launch in the non-reusable profile (for a slightly higher payload iirc), but then I discovered that the non-reusable F9 profil…

It doesn't have enough spare fuel for the descent/landing burns when lifting such a large payload.

Re: Falcon Heavy Launch [video]

#19

Post by mensetmanusman »

usrusr wrote: post #15

Now that Falcon 9 landings have become so routine, it feels surprisingly wasteful to see that mission profile with the center booster burning up without even trying. I wanted to write something about that lack of center booster reuse on falcon heavy feeling irrationally worse than a single F9 launch in the non-reusable profile (for a slightly higher payload iirc), but then I discovered that the non-reusable F9 profil…

Have to consider overall risk mitigation waste impact. E.g. if the additional complexity of adding a center booster increases risk of full mission failure, then, integrated over time, it can be a more wasteful decision if the goal isn’t to test that. Especially considering the satellite that would get destroyed and all the impact of having to rebuild that across the global supply chain.
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