4 ms·

What changed that made this cost-effective? 1) The companies pursuing this, SpaceX, Blue Orgin, etc., can't be the first to think of it. If the first stage acc

What changed that made this cost-effective? 1) The companies pursuing this, SpaceX, Blue Orgin, etc., can't be the first to think of it. If the first stage accounts for 75% of the cost of a launch, as one article I read says, I'm sure many have considered, going back to the first launches decades ago, how to reuse it. 2) The technology to land rockets vertically has existed for a long time, going back to the lunar lander at least.

codeulike 11y ago
2) The technology to land rockets vertically has existed for a long time, going back to the lunar lander at least. Landing the Lunar Lander on the moon is completely different to landing a tall, thin high-centre of gravity rocket full of explosive fuel, using AI because there's no crew onboard. Or did you mean something else? I'm pretty sure the first vertical landing of a rocket was only achieved in the last few years.
dbh937 11y ago
"New-space" aerospace companies are operating on a different funding framework from the old aerospace juggernauts. Instead of cost-plus funding that came almost solely from the government and which allowed rockets like ULA's Delta IV and Atlas V to stay competitive in the $300-400 million range without having to find ways to cut costs. SpaceX, Blue Origin, and Orbital Sciences, as well as other new companies, have to innovate in order to make their businesses feasible. Additionally, Blue Origin and SpaceX have different goals from traditional aerospace firms that requires them to drive costs down below what a government would require. Blue Origin want to offer rides to space to tourists; for that, their costs need to be low enough for a person to buy a ticket. SpaceX wants to land their rockets on Mars, and then take off again. Being able to land the first stage of the Falcon 9 allows them to perfect the landing and reuse of rockets on Earth, before taking that knowledge to Mars.
- hackuser 11y ago
  Thanks. I've heard the story but I haven't seen evidence of it, it smells too much like a marketing story (we're young and exciting, those old people are boring and stuck in the past), and it seems very unlikely: I don't buy that the 'old' companies wouldn't want to reduce their costs by 75%, greatly increasing demand for their very expensive service, greatly increasing their bottom line - even in a cost-plus arrangement. Usually changes like this result from a technical or economic development.
  - swax 11y ago
    Old companies don't want to reduce the cost - they like hundreds of millions of dollars per launch ;)
  - robotresearcher 11y ago
    So why didn't the old companies do it? They have the same access to technical and financial expertise as anyone, and deep pockets.
    - lmm 11y ago
      "Cost-plus" funding means they didn't have any incentive to reduce costs. The thing that got them money was keeping politicians onside, so it was more important to e.g. provide jobs in relevant states.
      - robotresearcher 11y ago
        I agree totally. I was responding to the parent who was challenging cost-plus as an explanation for Big-Co failing to bring down costs.
  - lsseckman 11y ago
    That's true, even with less pressure it would have been in their reach to work on those projects. Seems strange to be just happening now.
  - ZoFreX 11y ago
    It's not that we're young and exciting and the early attempts were old and boring. The comment you're replying to is pointing out the very different incentives between several private companies competing for and government-funded projects with totally different funding structures.
  - TeMPOraL 11y ago
    Different incentives = different goals. SpaceX had to cut costs down to even be remotely competitive, and they had the benefit of starting from scratch, with no prior commitments in design of machine shops, etc. and with access to several decades worth of spaceflight experience. And they have a drive, too. Mars is not a marketing story, Elon seems to really believe in doing it, and a lot of people at SpaceX buy into this vision.
deleted 11y ago
[deleted]
InclinedPlane 11y ago
Expendable rocket design is a local maxima which reduces fitness for reuse. This is because the typical, and traditional, optimizations all work against reuse. Reducing the number of engines on the first stage lowers cost and increases reliability and performance. And makes VTVL operations nearly impossible without adding additional engines (ballooning complexity, increasing stage cost, and reducing performance in an already extremely performance constrained system). Additionally, the traditional method for incrementally improving overall launch vehicle performance is to change the upper stage. By switching to a higher performance LOX/LH2 stage you can increase payload without redesigning the first stage, and without increasing gross liftoff weight. Even with the Falcon 9 they changed the second stage to improve performance, but they avoided the pitfall of making it much more advanced. On paper advanced upper stages seems like smart thing to do. You concentrate your engineering efforts on one of the smaller pieces of the rocket, and you improve performance without necessitating a full redesign. But this results in a vehicle with most of the cost in the upper stage. This development trajectory leads to a capable launcher, but one that is wholly unsuited for reuse. Reusing the first stage is now extraordinarily difficult, extraordinarily costly, and has little advantage (since most of the cost is in the upper stage anyway). You see the effects of this design pattern in most expendable launchers. Both the Delta IV and Atlas V boosters use a single engine in the first stage, and both use an RL-10 LOX/LH2 engine for the 2nd stage, an extremely expensive engine on its own, let alone when it's integrated into a high-tech stage (such as Lockheed-Martin's legendary Centaur line). The Ariane 5 has gone through 5 different generations of upper stage advancements, and it too has only one engine on its first stage. India's GSLV uses a solid first stage with hypergolic boosters and second stage and a LOX/LH2 3rd stage. Meanwhile, there hasn't been much pressure on rocket designers to be hard headedly pragmatic. Often times winning government contracts or even private investment meant convincing people of your beyond state-of-the-art designs that would leap frog the competition, rather than rely on common sense engineering and iterative advancements. That's how we got the Shuttle (which was supposed to be about 2 orders of magnitude cheaper to operate than it turned out to be), the X-33/VentureStar program, the NASP/X-30 program, Rotary Rocket, Pioneer Rocketplane, and all the other programs and startups that were cancelled when they ran out of money, ran into engineering problems, or both. The sensible thing is to try reusing some of the rocket and make the most of that from a cost perspective. Something that saw a bit of attention with the old DC-X program over two decades ago. One problem with that program was that it envisioned a new launcher that was mostly an SSTO, and aimed at building up from small scale rather than building toward reuse from full orbital scale. The genius of Musk and SpaceX has several facets: 1) Begin with expendable, but design with reuse in mind (high throttle ability in the first stage, most of the costs in the first stage), and work towards there iteratively. That way you get experience in a lot of the most important bits of the business: building orbital rockets, building rocket engines, building spacecraft, launching rockets. And you get cold, hard cash flowing into the company from launches. Cash that keeps the company in business, and finances further innovations. 2) Build reuse not as a different vehicle but as a "feature flag" on a common design. The difference between a reusable launcher and an expendable launcher for SpaceX is a mode selection, not an architectural difference. This means that you get operational testing of the vast majority of your flight hardware for your vehicle with every single expendable launch. This is a well-known risk mitigation strategy in software and other industries, and here it works marvelously. Prior to today's launch SpaceX had 14 previous launches of substantially the same hardware (counting only the v1.1 version). 3) Opportunistically use the first stage after stage sep. for experimenting with boost back and landing. From the very first v1.1 launch SpaceX has been aggressive at testing aspects of the landing and reuse flight mode, equipping stages with landing gear in many cases. This is a fantastic cost saving method as it takes what would be trash and transforms it into test vehicles being operated in typical flight profiles. This takes advantage of hundreds of millions of dollars of flight hardware to conduct an R&D test program on the cheap. Combine all of that together and you end up with a way to get from A (expendable rockets) to B (reusable rockets) without having to take on a ton of risk, without having to spend insane amounts of money, without having to design and operationally prove a brand new reusable vehicle design, and to build a revenue earning and self-sustaining business before being able to finish reusable vehicle development. It took a significant amount of foresight and savvy to be able to see that route and to execute on it. And yes, knowing what we know now it would have been easy to do this sort of stuff in the past, more so if we wanted to just throw money at it. But it wasn't obvious until being proven.
andygates 11y ago
A lot of people have tried to retrieve boosters. The Shuttle approach is suboptimal (solid boosters can't be throttled/relit/extinguished easily, the sea is evil, turnaround times are huge). ESA and the Russians and NASA have all thought about glide-back boosters and got mired in complexity. The new-space approach of "just the rocket, plus better control systems" is paying off, but it does take modern kit and thinking.

codeulike 11y ago

2) The technology to land rockets vertically has existed for a long time, going back to the lunar lander at least. Landing the Lunar Lander on the moon is completely different to landing a tall, thin high-centre of gravity rocket full of explosive fuel, using AI because there's no crew onboard. Or did you mean something else? I'm pretty sure the first vertical landing of a rocket was only achieved in the last few years.

dbh937 11y ago

"New-space" aerospace companies are operating on a different funding framework from the old aerospace juggernauts. Instead of cost-plus funding that came almost solely from the government and which allowed rockets like ULA's Delta IV and Atlas V to stay competitive in the $300-400 million range without having to find ways to cut costs. SpaceX, Blue Origin, and Orbital Sciences, as well as other new companies, have to innovate in order to make their businesses feasible. Additionally, Blue Origin and SpaceX have different goals from traditional aerospace firms that requires them to drive costs down below what a government would require. Blue Origin want to offer rides to space to tourists; for that, their costs need to be low enough for a person to buy a ticket. SpaceX wants to land their rockets on Mars, and then take off again. Being able to land the first stage of the Falcon 9 allows them to perfect the landing and reuse of rockets on Earth, before taking that knowledge to Mars.

hackuser 11y ago
Thanks. I've heard the story but I haven't seen evidence of it, it smells too much like a marketing story (we're young and exciting, those old people are boring and stuck in the past), and it seems very unlikely: I don't buy that the 'old' companies wouldn't want to reduce their costs by 75%, greatly increasing demand for their very expensive service, greatly increasing their bottom line - even in a cost-plus arrangement. Usually changes like this result from a technical or economic development.
- swax 11y ago
  Old companies don't want to reduce the cost - they like hundreds of millions of dollars per launch ;)
- robotresearcher 11y ago
  So why didn't the old companies do it? They have the same access to technical and financial expertise as anyone, and deep pockets.
  - lmm 11y ago
    "Cost-plus" funding means they didn't have any incentive to reduce costs. The thing that got them money was keeping politicians onside, so it was more important to e.g. provide jobs in relevant states.
    - robotresearcher 11y ago
      I agree totally. I was responding to the parent who was challenging cost-plus as an explanation for Big-Co failing to bring down costs.
- lsseckman 11y ago
  That's true, even with less pressure it would have been in their reach to work on those projects. Seems strange to be just happening now.
- ZoFreX 11y ago
  It's not that we're young and exciting and the early attempts were old and boring. The comment you're replying to is pointing out the very different incentives between several private companies competing for and government-funded projects with totally different funding structures.
- TeMPOraL 11y ago
  Different incentives = different goals. SpaceX had to cut costs down to even be remotely competitive, and they had the benefit of starting from scratch, with no prior commitments in design of machine shops, etc. and with access to several decades worth of spaceflight experience. And they have a drive, too. Mars is not a marketing story, Elon seems to really believe in doing it, and a lot of people at SpaceX buy into this vision.

deleted 11y ago

[deleted]

InclinedPlane 11y ago

Expendable rocket design is a local maxima which reduces fitness for reuse. This is because the typical, and traditional, optimizations all work against reuse. Reducing the number of engines on the first stage lowers cost and increases reliability and performance. And makes VTVL operations nearly impossible without adding additional engines (ballooning complexity, increasing stage cost, and reducing performance in an already extremely performance constrained system). Additionally, the traditional method for incrementally improving overall launch vehicle performance is to change the upper stage. By switching to a higher performance LOX/LH2 stage you can increase payload without redesigning the first stage, and without increasing gross liftoff weight. Even with the Falcon 9 they changed the second stage to improve performance, but they avoided the pitfall of making it much more advanced. On paper advanced upper stages seems like smart thing to do. You concentrate your engineering efforts on one of the smaller pieces of the rocket, and you improve performance without necessitating a full redesign. But this results in a vehicle with most of the cost in the upper stage. This development trajectory leads to a capable launcher, but one that is wholly unsuited for reuse. Reusing the first stage is now extraordinarily difficult, extraordinarily costly, and has little advantage (since most of the cost is in the upper stage anyway). You see the effects of this design pattern in most expendable launchers. Both the Delta IV and Atlas V boosters use a single engine in the first stage, and both use an RL-10 LOX/LH2 engine for the 2nd stage, an extremely expensive engine on its own, let alone when it's integrated into a high-tech stage (such as Lockheed-Martin's legendary Centaur line). The Ariane 5 has gone through 5 different generations of upper stage advancements, and it too has only one engine on its first stage. India's GSLV uses a solid first stage with hypergolic boosters and second stage and a LOX/LH2 3rd stage. Meanwhile, there hasn't been much pressure on rocket designers to be hard headedly pragmatic. Often times winning government contracts or even private investment meant convincing people of your beyond state-of-the-art designs that would leap frog the competition, rather than rely on common sense engineering and iterative advancements. That's how we got the Shuttle (which was supposed to be about 2 orders of magnitude cheaper to operate than it turned out to be), the X-33/VentureStar program, the NASP/X-30 program, Rotary Rocket, Pioneer Rocketplane, and all the other programs and startups that were cancelled when they ran out of money, ran into engineering problems, or both. The sensible thing is to try reusing some of the rocket and make the most of that from a cost perspective. Something that saw a bit of attention with the old DC-X program over two decades ago. One problem with that program was that it envisioned a new launcher that was mostly an SSTO, and aimed at building up from small scale rather than building toward reuse from full orbital scale. The genius of Musk and SpaceX has several facets: 1) Begin with expendable, but design with reuse in mind (high throttle ability in the first stage, most of the costs in the first stage), and work towards there iteratively. That way you get experience in a lot of the most important bits of the business: building orbital rockets, building rocket engines, building spacecraft, launching rockets. And you get cold, hard cash flowing into the company from launches. Cash that keeps the company in business, and finances further innovations. 2) Build reuse not as a different vehicle but as a "feature flag" on a common design. The difference between a reusable launcher and an expendable launcher for SpaceX is a mode selection, not an architectural difference. This means that you get operational testing of the vast majority of your flight hardware for your vehicle with every single expendable launch. This is a well-known risk mitigation strategy in software and other industries, and here it works marvelously. Prior to today's launch SpaceX had 14 previous launches of substantially the same hardware (counting only the v1.1 version). 3) Opportunistically use the first stage after stage sep. for experimenting with boost back and landing. From the very first v1.1 launch SpaceX has been aggressive at testing aspects of the landing and reuse flight mode, equipping stages with landing gear in many cases. This is a fantastic cost saving method as it takes what would be trash and transforms it into test vehicles being operated in typical flight profiles. This takes advantage of hundreds of millions of dollars of flight hardware to conduct an R&D test program on the cheap. Combine all of that together and you end up with a way to get from A (expendable rockets) to B (reusable rockets) without having to take on a ton of risk, without having to spend insane amounts of money, without having to design and operationally prove a brand new reusable vehicle design, and to build a revenue earning and self-sustaining business before being able to finish reusable vehicle development. It took a significant amount of foresight and savvy to be able to see that route and to execute on it. And yes, knowing what we know now it would have been easy to do this sort of stuff in the past, more so if we wanted to just throw money at it. But it wasn't obvious until being proven.

andygates 11y ago

A lot of people have tried to retrieve boosters. The Shuttle approach is suboptimal (solid boosters can't be throttled/relit/extinguished easily, the sea is evil, turnaround times are huge). ESA and the Russians and NASA have all thought about glide-back boosters and got mired in complexity. The new-space approach of "just the rocket, plus better control systems" is paying off, but it does take modern kit and thinking.