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Watch the SpaceX Falcon Heavy Rocket Launch Today

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Re: Watch the SpaceX Falcon Heavy Rocket Launch Today

#91

Post by MLR »

chasd00 wrote: post #46
Robotbeat wrote: post #37

Falcon Heavy is just a toe in the door of super heavy launch. BFR will have 31 engines at liftoff compared to Falcon Heavy's 27. BFR will be about twice the thrust of Falcon Heavy, and most importantly BFR is not just a launch vehicle (which gives SpaceX a big edge in deploying megaconstellations of low-latency internet satellites), but the upper stage part will be a spacecraft capable of reentering the Earth's atmos…

yeah i think BFR and the upgraded Falcon 9 pretty much obsoletes Falcon Heavy almost immediately. The Heavy just took so long to put together, it was suppose to fly 4 or 5 years ago right? I've heard it reported that the Falcon Heavy engineering was much harder than anticipated. Does anyone know what some of the major obstacles were? The concept seems straightforward but where did they start getting into trouble?

One of the things that slowed it down a lot was the continual development of the Falcon 9.

With the Block 3/4/5 series of the Falcon 9 (5 is the final design and mostly focused on reusability upgrades, 4 is interim) they have a relatively stable base rocket to develop the Heavy variant against.

Re: Watch the SpaceX Falcon Heavy Rocket Launch Today

#93

Post by jacquesm »

chasd00 wrote: post #46
Robotbeat wrote: post #37

Falcon Heavy is just a toe in the door of super heavy launch. BFR will have 31 engines at liftoff compared to Falcon Heavy's 27. BFR will be about twice the thrust of Falcon Heavy, and most importantly BFR is not just a launch vehicle (which gives SpaceX a big edge in deploying megaconstellations of low-latency internet satellites), but the upper stage part will be a spacecraft capable of reentering the Earth's atmos…

yeah i think BFR and the upgraded Falcon 9 pretty much obsoletes Falcon Heavy almost immediately. The Heavy just took so long to put together, it was suppose to fly 4 or 5 years ago right? I've heard it reported that the Falcon Heavy engineering was much harder than anticipated. Does anyone know what some of the major obstacles were? The concept seems straightforward but where did they start getting into trouble?

BFR could easily run into similar delays giving Falcon Heavy a longer useful life.

Re: Watch the SpaceX Falcon Heavy Rocket Launch Today

#94

Post by thaumaturgy »

TeMPOraL wrote: post #87
thaumaturgy wrote: post #84

Earlier quoted context omitted.

I'm not sure I've ever thought it was impossible -- I've learned to be more circumspect about that kind of thing as I'm nearing 40 -- but I tried imagining the fine detail engineering that would be required to do it and was totally overwhelmed. I mean, take a yardstick or short rod or something, and try to balance it upright on the tip of your finger. That's basically what they're doing, but with a -rocket-. It's ama…

The rocket has its center of mass very low during landing, as it's mostly an empty shell by this point, with heavy engines at the bottom. So take a meter tape, pull it out a bit, lock and try to balance that. Much easier, right? The magic is in a) ensuring the whole construct survives reentry, and b) timing the landing burn - even a single Merlin engine is too powerful for the almost empty rocket to hover, so they ne…

I decided I had no way to guess on the mass distribution of fuel, engine, and airframe, plus wind shear, so I went with the hard scenario. If anybody knows the numbers for this, I'd love to hear it!

Re: Watch the SpaceX Falcon Heavy Rocket Launch Today

#95

Post by golergka »

emilecantin wrote: post #54
chasd00 wrote: post #46

Earlier quoted context omitted.

yeah i think BFR and the upgraded Falcon 9 pretty much obsoletes Falcon Heavy almost immediately. The Heavy just took so long to put together, it was suppose to fly 4 or 5 years ago right? I've heard it reported that the Falcon Heavy engineering was much harder than anticipated. Does anyone know what some of the major obstacles were? The concept seems straightforward but where did they start getting into trouble?

I remember reading a quote from Elon where he says that at some point, they realised it's less "strapping three cores together" than "flying three cores in very close formation" The stresses involved are truly enormous, and the whole thing must be very well balanced to avoid putting even more stresses on the frame. Something as stupid as fueling the rocket needs to be done with care, as they're dealing with super-chi…

After countless hours of experimenting with additional struts in KSP to keep my rockets from going through RUD I have a weird feeling as if I understand this on some level. Rationally, I don't think that I have any real understanding of rocket science from KSP - but that weird feeling just won't go away.

Re: Watch the SpaceX Falcon Heavy Rocket Launch Today

#96

Post by jacquesm »

ryanwaggoner wrote: post #83
Faaak wrote: post #63

Earlier quoted context omitted.

I think there's a little difference between thousands of engineers building a rocket and 4 idiots crashing a plane down…

As horrific as 9/11 was, it’s not fair to characterize it as 4 idiots bringing down a plane. It was 19 people who led a coordinated attack that took hundreds of people, millions of dollars, and years to plan and execute. In the process, they brought down 4 airplanes, damaged the pentagon, and toppled TWO skyscrapers, killing thousands of people in the process. Looking back at the 17 years since, they indirectly start…

Their biggest success was to enlist their foes in achieving their goals. That's the part I will never understand.

Re: Watch the SpaceX Falcon Heavy Rocket Launch Today

#97

Post by toomanybeersies »

avmich wrote: post #40
toomanybeersies wrote: post #15

Earlier quoted context omitted.

Personally I was more excited about the RocketLab launch. This to me feels like a variation on a theme. RocketLab was in may ways a breakthrough. First orbital launch from New Zealand and first orbital launch using electric turbopumps.

I was sad when I learned they've launched half as much as Falcon-1 for (rumored?) almost twice more money spent some 15 years later. On the other hand, a good demonstration of composites - and yes, electropumps are a good opportunity which now is on the list of "already done".

Yes, their cost per kg for launching is higher than SpaceX.

But it's their first launch from a new company. It's expected to cost some more to start with. I presume the price is going to come down quite significantly over the next few years.

RocketLab will never be as cheap, but the business plan isn't to compete on price. The business model is that with smaller rockets you can have much higher launch cadence, much higher throughput (i.e. you can book a launch and have it launched a week later), and more customisable orbits (since it's cheaper to book out an entire launch).

Re: Watch the SpaceX Falcon Heavy Rocket Launch Today

#98

Post by hinkley »

angrygoat wrote: post #45
chasd00 wrote: post #21

Earlier quoted context omitted.

hah i felt the same way. I remember when the Sky Crane was used to put Curiosity down on Mars, I thought there's just no freaking way that's going to work but they pulled it off. When SpaceX started talking about landing boosters I shook my head again but then they did it. The older I get the more blown away (and humbled) I am at what people are capable of achieving. On a lighter note there's a Simpons line when Home…

nitpick - it was Curiosity that came down on Mars using a sky crane, Odyssey was an earlier mission

I had to look it up. Curiosity was the lander, Odyssey is the relay satellite. Both are the same mission.

Before the sky crane we had the bouncy ball, and both had supersonic parachutes which is also a mind bender.

Re: Watch the SpaceX Falcon Heavy Rocket Launch Today

#99

Post by greenhouse_gas »

sitkack wrote: post #51
chasd00 wrote: post #21

Earlier quoted context omitted.

hah i felt the same way. I remember when the Sky Crane was used to put Curiosity down on Mars, I thought there's just no freaking way that's going to work but they pulled it off. When SpaceX started talking about landing boosters I shook my head again but then they did it. The older I get the more blown away (and humbled) I am at what people are capable of achieving. On a lighter note there's a Simpons line when Home…

This whole thread should review Clarke's Three Laws[0] 1. When a distinguished but elderly scientist states that something is possible, they are almost certainly right. When they state that something is impossible, they are very probably wrong. 2. The only way of discovering the limits of the possible is to venture a little way past them into the impossible. 3. Any sufficiently advanced technology is indistinguishabl…

The (counter) corollary to rule #1: They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown.

Re: Watch the SpaceX Falcon Heavy Rocket Launch Today

#100

Post by arnaud12 »

Klathmon wrote: post #82
arnaud12 wrote: post #61

Earlier quoted context omitted.

I find the first stage recovery very impressive too, but did they manage to reduce the launch cost since they started reusing the rockets?

Yes, significantly. I don't have numbers on hand right now, but I believe it has been a large success in that department.

I'm pretty sure they save money but I've never seen numbers confirming that information either.
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