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SpaceX's New Spin on Falcon 9

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Re: SpaceX's New Spin on Falcon 9

#71

Post by avmich »

nickff wrote: post #11
cryptoz wrote: post #7

Earlier quoted context omitted.

Part of the Shuttle's reusability problems stemmed from Congress (and other decision-makers) forcing NASA to use facilities in ~40-50 different states and multiple subcontractors. And, full & rapid reusability was never in the Shuttle plans. They aimed for moderate reusability and then failed spectacularly at that. SpaceX is much more centralized and much more efficient. There are certainly comparisons to me made, an…

We should put less focus on reusability, and pay more attention to labor (inspection and repair time) per launch. If you compare SpaceX and NASA under this paradigm, or by looking at launch cost per unit of mass, SpaceX has long since surpassed all other launch providers. The shuttle had a number of issues, including design issues due to DoD requirements, engine pressure issues due to internal NASA priorities, and bu…

Here is an example of how inspection could be done by professionals:

https://www.youtube.com/watch?v=5dWCI4S4fGg

Re: SpaceX's New Spin on Falcon 9

#72

Post by avmich »

FD3SA wrote: post #9

"It's about a 30% increase in performance, maybe a little more. What it does is it allows us to land the first stage for GTO missions on the drone ship." I am constantly blown away by SpaceX. This is an absurd level of improvement for an already mature, commercially successful rocket. If even 1% of the world's companies in other sectors worked this well, I can only imagine how much our quality of life would improve.…

Don't want to diminish SpaceX achievements, but for some comparable systems results could be similarly interesting. For example, Soyuz rockets are launched at least twice (at least 12 per year, https://en.wikipedia.org/wiki/List_of_R-7_launches_%282010%E... ) more often than Falcon last year (highest frequency so far), their pumps and chambers, modules of first stage are manufactured in corresponding numbers (6 pumps per rocket, 20 main thrust chambers for 1 and 2 stages alone, 4 modules of first stage), the rocket is largely - though not completely - manufactured in one closely tied cluster of companies (in Samara city on Volga river, where it is also designed and upgraded). Admittedly these results came after half a century of incremental improvements - but it's interesting to compare SpaceX results with some other offerings.

Re: SpaceX's New Spin on Falcon 9

#73

Post by avmich »

ufmace wrote: post #43
krschultz wrote: post #22

SpaceX continues to be a PR machine. This news comes barely 24 hours after a significant delay due to a helium tank problem - http://spaceflightnow.com/2015/03/17/spacex-puts-off-next-fa... . I'm not saying SpaceX has a fundamental problem, I just find it interesting how obvious PR planted articles are.

Interesting that you're getting downvoted here... I do like and support SpaceX, but they sure seem to have an impressive PR machine also. They seem to get a lot more buzz and press than every other space company combined. Maybe it's a Silicon Valley-inspired tradition of working with and courting the press, as opposed to a more secrecy-focused environment in companies that mostly do military contracting?

Impressive PR machine, yes. However, von Braun reportedly said "Late to bed, early to rise, work like hell - and advertise" so underscoring the importance of PR.

We need to judge both by PR and actual performance. So far there is plenty of both to talk about.

Re: SpaceX's New Spin on Falcon 9

#74

Post by tsotha »

toomuchtodo wrote: post #14
martythemaniak wrote: post #8

Currently they have to throw away the rockets used for GTO missions (around half of them) and can only attempt landings on LEO missions such as the ISS resupplies. Given their last few landing attempts, it's pretty likely that they'll be able to land a rocket sometime this year, which means that starting next year they might be able to reuse all of their F9 Rockets. A lot of customers may not want to fly on a used ro…

The rocket is paid for with its primary mission. Elon has said that the fuel is a very small cost compared to the entire launch, so I would assume the cost to refly a "used" rocket is going to be orders of magnitude cheaper than the original flight. I could see SpaceX segmenting their customers into two tiers: mission completion sensitive, and cost sensitive, with who gets which rockets straightforward.

>The rocket is paid for with its primary mission. Elon has said that the fuel is a very small cost compared to the entire launch, so I would assume the cost to refly a "used" rocket is going to be orders of magnitude cheaper than the original flight.

Engineers have been scratching their heads for decades trying to figure out where all the money goes. For shuttle launches, depending on who's doing the accounting, fuel was something on the order of 2% of total launch costs. And the shuttle was reusable as well.

I think it's that disparity that attracted Musk to the rocket business in the first place. You look at the cost breakdowns and think "What? How can this be so expensive?" If everything goes his way he'll have cut the vehicle cost by a factor of at least 20 by the time he's done.

Re: SpaceX's New Spin on Falcon 9

#75

Post by tsotha »

ChuckMcM wrote: post #47
martythemaniak wrote: post #8

Currently they have to throw away the rockets used for GTO missions (around half of them) and can only attempt landings on LEO missions such as the ISS resupplies. Given their last few landing attempts, it's pretty likely that they'll be able to land a rocket sometime this year, which means that starting next year they might be able to reuse all of their F9 Rockets. A lot of customers may not want to fly on a used ro…

> Anyway, these are probably the most exciting times in > spaceflight since the 60s! Yes it is, and we get to use technology from the future this time :-). It is bittersweet for me, the opportunity lost to keep funding NASA at a reasonable level could have a lot of useful data in the 'bank' as it were, but by and large much of the stuff that makes what SpaceX does possible is relatively new. In particular the avionic…

>It is bittersweet for me, the opportunity lost to keep funding NASA at a reasonable level...

We spent more than enough money on NASA to have been decades ago where SpaceX is today. Unfortunately, Congress sees NASA as a source of patronage funding and not a space agency. If it had been run as a space program the shuttle would have been cancelled in the early '80s when it became The Monster That Ate The Budget.

Re: SpaceX's New Spin on Falcon 9

#76

Post by DanielBMarkham »

tsotha wrote: post #75
ChuckMcM wrote: post #47

Earlier quoted context omitted.

> Anyway, these are probably the most exciting times in > spaceflight since the 60s! Yes it is, and we get to use technology from the future this time :-). It is bittersweet for me, the opportunity lost to keep funding NASA at a reasonable level could have a lot of useful data in the 'bank' as it were, but by and large much of the stuff that makes what SpaceX does possible is relatively new. In particular the avionic…

>It is bittersweet for me, the opportunity lost to keep funding NASA at a reasonable level... We spent more than enough money on NASA to have been decades ago where SpaceX is today. Unfortunately, Congress sees NASA as a source of patronage funding and not a space agency. If it had been run as a space program the shuttle would have been cancelled in the early '80s when it became The Monster That Ate The Budget.

I may disagree about which programs should be cut or not, but I agree with your sentiment: we could have paid NASA 10x and not advanced significantly. It would have just all flowed into various Congressional districts. We're advancing in spaceflight because we have no other choice: the money's ran out -- years ago, really.

Political systems of organization (organizations of people set up based on the desires of the electorate and controlled by politicians) exist and act for political reasons. Getting to the moon was a political goal, not a scientific one. The shuttle and ISS were political goals. Even privatizing like we've done is a political act.

We really need to build a mass driver on Earth for cargo launches. It would not be crazy expensive, and it would make a huge difference in the cost of LEO construction. Our order of priority should be 1) reduce cost to LEO to 1/100th of what it currently is, and 2) make orbital construction costs as close as possible to other oddball ground-based construction costs, like building underwater or in Antarctica. If we can focus on dropping costs, there are thousands of industries and other actors that will do some really cool stuff with the tools we provide. But that's a really tough thing to sell politically. The real reason we have SpaceX is because nobody wanted to explain to the folks how we lost a huge amount of our launch capacity when we retired the shuttle.

Re: SpaceX's New Spin on Falcon 9

#77

Post by ansible »

NamTaf wrote: post #66
toomuchtodo wrote: post #27

Earlier quoted context omitted.

Yes, definitely cost prohibitive from a fuel perspective to change orbits, but the vehicle could be safed for future use. I do not have enough information as to whether though would be valuable unless Tesla as some way to produce fuel on-orbit for the waiting, safed second stages.

You'd have to keep boosting it where it is, which means it needs extra thrusters. Otherwise it'll just decay. Also, changing orbits is expensive . Remember you need to change both height and angle, and the delta-V is huge. Bringing them back down is almost certainly the easiest option.

If the 2nd stage at least had a small solar panel and magnetic tether, it could (slowly) change orbits into something useful. Not sure what the weight penalty for a minimally viable system would be. For the 2nd stage, every gram counts, much more so than for the 1st stage.

Re: SpaceX's New Spin on Falcon 9

#78

Post by lmm »

TeMPOraL wrote: post #39
toomuchtodo wrote: post #27

Earlier quoted context omitted.

Yes, definitely cost prohibitive from a fuel perspective to change orbits, but the vehicle could be safed for future use. I do not have enough information as to whether though would be valuable unless Tesla as some way to produce fuel on-orbit for the waiting, safed second stages.

Well, FWIW, it works in Kerbal Space Program. But as you said, this would require for the fuel to be brought from somewhere else than Earth's gravity well. Maybe Planetary Resources will find some kerosene on a near-Earth asteroid?

No it doesn't, not if you launch satellites where customers want them. Kerbal Space Program should really bring home the big fundamental about orbital mechanics: plane changes are really expensive.

Re: SpaceX's New Spin on Falcon 9

#79

Post by antimagic »

avmich wrote: post #72
FD3SA wrote: post #9

"It's about a 30% increase in performance, maybe a little more. What it does is it allows us to land the first stage for GTO missions on the drone ship." I am constantly blown away by SpaceX. This is an absurd level of improvement for an already mature, commercially successful rocket. If even 1% of the world's companies in other sectors worked this well, I can only imagine how much our quality of life would improve.…

Don't want to diminish SpaceX achievements, but for some comparable systems results could be similarly interesting. For example, Soyuz rockets are launched at least twice (at least 12 per year, https://en.wikipedia.org/wiki/List_of_R-7_launches_%282010%E... ) more often than Falcon last year (highest frequency so far), their pumps and chambers, modules of first stage are manufactured in corresponding numbers (6 pumps…

And how many launches can a single R7 make? That's the difference that has all of our jaws droppping, because it's going to reduce the price for access to space by an order of magnitude.

Re: SpaceX's New Spin on Falcon 9

#80

Post by TeMPOraL »

lmm wrote: post #78
TeMPOraL wrote: post #39

Earlier quoted context omitted.

Well, FWIW, it works in Kerbal Space Program. But as you said, this would require for the fuel to be brought from somewhere else than Earth's gravity well. Maybe Planetary Resources will find some kerosene on a near-Earth asteroid?

No it doesn't, not if you launch satellites where customers want them. Kerbal Space Program should really bring home the big fundamental about orbital mechanics: plane changes are really expensive .

There are ways to make plane changes cheap (do them high enough, use gravity assist, etc.) and they could be useful when shipping fuel higher from Earth's gravity well, but I admit, current space missions are nowhere near that complicated.

Also, while expensive, plane changes are still cheaper delta-V-wise than punching through the soup our atmosphere is.

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