non-rotating skyhook Archives - Opening the High Frontier

Guiding Vision

All projects have a guiding vision. No project can exist without one. The guiding vision that led to the formation of NASA was created by Wernher Von Braun in the 1950s. It consisted of using large multi-stage rockets for launching satellites, cargo rockets, and manned space shuttles into Earth orbit.

The purpose for this launch system was twofold. It was to allow the United States military to place reconnaissance and communications systems in Earth orbit so as to help prevent a global nuclear war, or allow the United States to dominate such a war should one get started. Its second purpose was to build a space station in Earth orbit that would serve as an assembly site for putting together manned spacecraft that would go to the Moon and Mars.

Space itself was not thought of as a destination in this vision. Space was the high ground for the military, and a place to be crossed in order to go to another planet. Due to the high cost of getting to orbit, space was also not thought of as a place for large scale commercial activities such as orbital industries and asteroid mining. Space was thought of as a place for military and government activities along with a few civilian communications satellites. This is the guiding vision that NASA and the military have been operating on ever since.

There have been other visions.

Over one hundred years ago, Konstantin Tsiolkovsky, the man who worked out the mathematics of rocketry and spaceflight, envisioned space as a new home for mankind. A place where mankind would continue to grow and evolve long after our solar system has died. His vision started with people moving out into the solar system where they would build habitats the size of small moons and who would harvest the asteroids for the raw materials that were needed to live and grow there. Eventually, as our technology improved and as the solar system became more crowded, the more adventurous would eventually take on the challenge of going to other stars, thereby starting a process that would lead to mankind spreading out across the galaxy. It was, and still is, an incredible vision.

In 1976, Gerard O’Neill proposed a similar idea in his book, The High Frontier. This is the book that introduced the world to the idea of Space Colonies, and of space being not just a place to travel through, but as a place to live and build a civilization. The only thing that was missing from this vision was a realistic concept for a launch system that would make spaceflight affordable enough to make this possible.

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Today

From the very beginning, most people who support and follow the space program, do so with the idea that it will eventually lead to the creation of a spacefaring civilization. Yet here we are, 50 years after the first manned Moon landing, and no progress has been made towards opening up the high frontier for development and settlement. Yes, there has been plenty of space science in the form of unmanned spacecraft exploring the solar system, space telescopes for exploring the stars, and space stations for studying the long term effects of zero gravity on humans, but that is it. Where are the orbital factories, orbiting hotels, the manned spacecraft for exploring the solar system, the outposts on the Moon and Mars, the asteroid mining companies, and the large rotating space stations full of people engaged in the development and settlement of space? Where are they? Why don’t they exist? The answer is simple, they don’t exist because NASA is operating on a different guiding vision. If you want to see these things occur then it will be necessary to give NASA a different guiding vision. That guiding vision comes from the President of the United States. The President of the United States gets his input from the American people. So it all comes down to us. What kind of space program do we all want? Do you want one like we have today that does space science and manned spaceflight for only a very few, or do you want one that includes developing the technologies that will make spaceflight affordable to everyone so that all the dreams of space become possible?

Think for a moment, how many of you are truly content with the space program we have today? How many of you are content with NASA’s plans for the next ten years and the rate of progress that is being made on those plans? Do you think those plans will lead to the opening of the high frontier so that anyone who has the dream and desire to go there will be able to go to a spaceport and buy a ticket?

If you are not happy with what is happening, ask yourself what kind of program you would like it to be. Would you choose the space program of today where only a small handful of people get to go to a space station in Earth orbit every year? Would you choose the planned space program of tomorrow, the one that consists of a small, man-tended space station in lunar orbit that will hopefully be the beginning of a return to the Moon in 2028 and maybe a manned mission to Mars 10 or 20 years after that? Or would you rather have a space program that makes spaceflight affordable to everyone so that orbital industries, orbital hotels, commercial asteroid mining operations, commercial ice mines on the Moon, commercial spacecraft for going to the Moon, Mars, and the asteroids, all exist? A program where all of this is done in a fraction of the time and at a fraction of the cost of what NASA currently requires? Which one of these excites you? Which one of these would you like to support and see happen?

The key ingredient that is necessary to make all these commercial activities possible, is making spaceflight affordable to everyone. Currently, it costs $82 Million to send an astronaut to the International Space Station on a Soyuz spacecraft. Obviously, not too many people can afford that. The Dragon 2 spacecraft is supposed to be able to carry a pilot and 6 passengers to the International Space Station for $120 Million. That works out to $20 Million per passenger. While that is a huge improvement over the Soyuz, it is still not a price that many people can afford. In order for commercial manned space activities to start, the cost of getting a person to orbit will need to drop down to the $200,000 dollar range or less. For really large scale space settlement to occur, the price to orbit will need to drop even lower than that. The only known launch concept that can be affordably built with existing technology that has the ability to do this is a Combination Launch System that includes a non-rotating skyhook.

Think about that for a moment. A way to make spaceflight affordable to everyone is truly within our reach. What kind of life would you choose for yourself if you could go to a spaceport and purchase a ticket to orbit and beyond? Would you go to Mars? Would you take a job at a shipyard out near the Moon building spaceships, satellite solar power stations, and Space Colonies? How about signing on as a crew member to a spaceship that is going asteroid mining where you have a good chance of coming home a multi-millionaire? Or would you take any job in space that you could get so that you could build a spacecraft in your spare time and go homestead an asteroid when it was done? In this universe of affordable to everyone spaceflight, if you are college age, you could even apply to go to the United States Space Force Academy to become an officer in the US Space Force. With the skills you will learn there you could get any job in space you want. So what would you choose? Really think about this, we are standing right at the edge of the most amazing future imaginable. All that is needed is to make spaceflight affordable to everyone. This will make possible a future that will make all the possibilities of the past look like nothing in comparison. It is a future without limit. What would you choose for yourself in this future?

If you are happy with the space program of today and its plans for tomorrow then there is nothing for you to do. If you are like me and you want more than that, then it is time to write a letter to the President of the United States and tell him that it is time to enlarge NASA’s mission statement to include the development of affordable to everyone spaceflight. Should you write the President, be sure and send copies of your letter to the Vice President and the head of NASA. You might also want to think about including a copy of this article with your letter. You have nothing to lose by doing this and everything to gain. Let’s make all our dreams of space come true, write the President and tell him about the future you want.

Ad Astra (To the Stars)

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Note: For those of you who are new to this website, this site is about making spaceflight affordable to everyone so we can finally start building the most incredible civilization the world has ever seen. A civilization that will include planets, asteroids, moons, space-based industries, and space colonies throughout the solar system. For those of you who are fans of space exploration but are new to the subject, the best way to read this site is to start at the beginning and read through to the most current article. If you are already familiar with the subject then feel free to jump around.

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A Vision of the Future

A new video!

This video is about our history of achievements and what that means for our future.

It is also about a vision for making spaceflight affordable to everyone so we can start building a spacefaring civilization.

If this is something that appeals to you, help make it happen by sharing this video with everyone you know.

For more information on this subject read the following articles.

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Opening the High Frontier (the video)

A couple of months ago I started working on a new presentation for the Combination Launch System concept that was to be given at a conference I was thinking of going to. As I worked on it, the presentation kept growing and evolving until I had the idea of making it into a video. As a video it has continued to grow and evolve even more, improving with each change. Even now, after all this time and effort, I am still not 100% sure it is finished, but it feels like the time is right to put it out there in the world and hear what people have to say about it.

I hope you enjoy watching it and I look forward to your comments.

Post Script For all of you who have made comments and suggestions on the video – Thank You. I have done my best to incorporate all of your suggestions into it and the end result is much better.

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Space Exploration and the Future

Affordable transportation systems are what make civilizations possible. It has been that way throughout human history. The same is true of space. Without an affordable way of getting into space, a program of sustained human space exploration that has the potential of growing into a spacefaring civilization will remain an unobtainable dream.

You can see the truth of this in the total number of launches per year. The total number of launches to orbit per year worldwide averages somewhere between 80 and 90. It has been that way for the last 30 years. Based on this, space is not a growth industry. In addition, most of those launches are Earth-orbiting satellites. The total number of manned flights for the same period has averaged about 5 per year and none of those went higher than low Earth orbit.

When you think about those numbers in terms of a sustained program of human space exploration that has the potential of growing into a spacefaring civilization, it becomes clear that we are not even close to getting started. For that to happen, we need to dramatically increase our flight rate.

Equally obvious is the fact that this isn’t going to happen based on NASA’s plans for manned spaceflight over the next decade and beyond.

The reason for this is the high cost of spaceflight.

Now imagine what will be possible once we have affordable to everyone spaceflight.

We can return to the Moon, go asteroid mining, go to Mars, and start building the most incredible civilization the world has ever seen. A civilization that will include planets, moons, asteroids, space-based industries, and space colonies scattered throughout the solar system.

People will be able to buy a ticket to an orbiting hotel for a weekend getaway. People will be able to go to the Moon for their vacation. People will be able to get jobs in space and buy a home on a space station or a space colony. People will be able to build their own spacecraft in their spare time and either go asteroid mining or go homestead an asteroid. It will also be possible to buy a ticket for a trip to Mars or the asteroid belt.

The possibilities are truly unlimited. The only limits will be your imagination, your courage, and how hard you are willing to work to make it happen.

Without affordable to everyone spaceflight, none of this is possible and all we can do is talk about it.

Not too long ago I presented the idea of a combination launch system to a group of space advocates. A combination launch system is a launch system that can be affordably built with existing materials and technology that will make spaceflight affordable to everyone. It works by reducing the amount of apparent velocity the launch vehicle needs to achieve to reach orbit. This allows the launch vehicles to be built 1/10th the size of existing launch vehicles and to be made as single stage vehicles that can make multiple flights per day. It is a system that will open up the high frontier for everyone.

My presentation generated a lot of interest, excitement, and discussion in the group. The next day, in response to that interest, the group leader got up on stage and said, “We are not interested in how we get into space, we are only interested in what comes after!”

I was truly surprised by how much applause he got for that statement. His statement also brought the discussion about the combination launch system to a complete halt.

My question to everyone is simple, “is it really that difficult to understand that affordable to everyone spaceflight is the true foundation that will allow the human race to become a spacefaring people?”

In my experience, it is not possible to build anything without a proper foundation in place, and affordable to everyone spaceflight is the foundation for our becoming a spacefaring people.

Today’s rockets, including the partially reusable ones from SpaceX, will never get the cost of spaceflight down to an amount that will make spaceflight affordable to everyone. They are too big, too expensive, their flight rate is too low, their planned operational life is too short, and their payload fraction is too small. To make spaceflight affordable to everyone it will be necessary to use a different approach. That is what a combination launch system is. It is a different way of getting into space that is based on existing technology that will solve all those problems and make spaceflight affordable to everyone.

If manned space exploration and the building of a spacefaring civilization is something that interests you I hope you will continue reading the articles on this website. Once you are done with that I would like you to consider writing a letter to President Trump or to Vice President Pence about making the building of a combination launch system part of NASA, or the soon to exist Space Force.

It is time for us to do this.

It is time for us to be greater than great.

It is time to make our dreams of the future into reality.

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Building a Spacefaring Civilization

Space, the final frontier.

Today, it is a place of dreams.

Tomorrow, it will be the place of our future.

There have been many visions of our future in space. Visions that include manned spacecraft exploring the solar system,

asteroid mining,

cities on other worlds,

space colonies,

and someday, starships.

In short, space is a place of endless possibilities, endless opportunities, endless wealth, endless dreams, and the place where we will build a spacefaring civilization that will someday spread to the stars.

Some people see our move into space as an option. Others see it as a necessity. Jeff Bezos recently said,

“We must lower the cost of access to space to do these grand things that we’re talking about. This is not something we can choose to do. This is something we must do.”

He is not the first person to say this. The number of people who have made similar statements is too long to list. The collective message is clear. We are in the process of outgrowing our home planet and it is time for us to learn to live and fly in a larger universe if we are to survive.

So why haven’t we done this?

The answer to that is cost.

Today, even with the reusable rockets that are being built by SpaceX and others, the cost of spaceflight is still too high to make building a spacefaring civilization possible. To create that reality we will need to be able to launch thousands of tons and thousands of people into space for a tiny fraction of what we pay today.

That is what this blog is about. How spaceflight can be made affordable to everyone so that we can finally start building that spacefaring civilization.

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The idea of multistage rockets, space travel, and building a spacefaring civilization got its start in the late 1800s when Russian mathematician Konstantin Tsiolkovsky derived the rocket equation. This is the equation that calculates how much propellant a rocket needs to carry to reach a certain speed. This equation is at the heart of everything we do with space travel. It is this equation that explains why spaceflight is so expensive and why we have not been able to start building a spacefaring civilization.

An example of this is the Space Shuttle.

The Space Shuttle had a take-off weight of 5 million pounds. Its maximum payload to low Earth orbit was 50,000 pounds. The reason it had a take-off weight 100 times the size of its payload was the amount of propellant it needed to reach the speed of low Earth orbit.

In order for the Space Shuttle to fly to the International Space Station, it had to go even faster. As a result, it could only carry 25,000 pounds of payload there. This means that for a trip to the International Space Station, the Space Shuttle required a take-off weight that was 200 times the weight of the payload.

Now, let’s take a look at what this high propellant fraction did to the cost.

The total cost to fly the Space Shuttle was $1.5 billion dollars per flight. Breaking that down to dollars per pound of useful payload, the Space Shuttle cost $30,000 dollars per pound to low Earth orbit, and $60,000 per pound when flying to the International Space Station.

Obviously, not very affordable.

There are two reasons for this. First, is the amount of propellant that is required to reach the speed of orbit. Second, is the small amount of useful payload delivered compared to the overall size and cost of the launch vehicle.

This is a problem that exists for all past, and currently existing launch vehicles.

One example of this is the Titan 2 launch vehicle that was used to launch the Gemini spacecraft into low Earth orbit back in the 1960s.

It had a takeoff weight of 331,000 pounds and a gross payload to low Earth orbit of 7,900 pounds. If it had been used as a cargo carrier for hauling freight to a low Earth orbit space station like Skylab, its estimated useful payload capacity would have been in the neighborhood of 2,700 pounds. That is a take-off weight to payload weight ratio of 120:1.

Another example is the Saturn 1B with Apollo spacecraft.

It had a take-off weight of 1.3 million pounds and a gross payload capacity of 44,000 pounds when flying to the Skylab space station. The Apollo spacecraft had a launch weight of 32,000 pounds, which left 12,000 pounds for useful payload. That is a take-off weight to payload weight ratio of 108:1.

A more modern example of this is the Falcon 9 rocket with Dragon spacecraft.

The Falcon 9 with Dragon has a take-off weight of 1.2 million pounds. It can deliver 6,000 pounds of useful payload to the International Space Station. Like the Space Shuttle, it has a take-off weight to payload weight ratio of 200:1 for this mission. Its cost per flight, including the cost of flying the Dragon, is approximately $120 million dollars. That results in a cost of $20,000 dollars per pound delivered to the International Space Station. That is 1/3rd of what the Space Shuttle cost.

The last example is the Falcon Heavy launch vehicle with Dragon spacecraft.

This vehicle has a take-off weight of 3.1 million pounds and should be able to deliver approximately 16,500 pounds of useful payload to the International Space Station when both boosters and the core stage are recovered. That is a take-off weight to payload weight ratio of 188:1. Assuming that the Falcon Heavy with Dragon spacecraft costs $120 million dollars per flight when the boosters and core stage are recovered, the cost per pound to the International Space Station drops to approximately $7,000 dollars per pound. That is approximately 1/8th of what the Space Shuttle cost.

Both the Falcon 9 and the Falcon Heavy reduce the cost of getting to orbit by making as much of the rocket reusable as possible, and by simplifying the design so it is less expensive to build, fly, and maintain. Unfortunately, neither of these launch vehicles has been able to reduce the amount of propellant that is required to reach the speed of orbit. Just like the Space Shuttle, both the Falcon 9 and the Falcon Heavy have a take-off weight to payload weight ratio of approximately 200:1 when flying to the International Space Station. This places a limit on how much cost reduction can be achieved by simplifying the design and making the first stages of the vehicle reusable. So, while both of these vehicles are a wonderful improvement over the Space Shuttle, neither of them is low enough in cost to allow us to start building a spacefaring civilization. For that to happen the cost to orbit will need to drop to a few pennies on the dollar of what the Falcon Heavy costs. That just isn’t going to be possible using launch vehicles that have take-off weight to payload weight ratios this high. In order to get the cost down low enough to build a spacefaring civilization, we need to rethink how we get into space.

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Back in the early-mid 1800s, steamships had a similar problem to today’s launch vehicles. The steam engines of the day burned so much coal that the ships were limited in how far they could travel and still have enough room left over to carry a worthwhile amount of cargo. They solved this problem by breaking up the longer shipping routes into shorter lengths with strategically placed coaling stations. This allowed the early steamships to travel the globe while carrying a lot less coal and a lot more cargo. This significantly reduced the cost of shipping goods and people around the world while allowing the shipping companies to operate at a higher profit margin. It was a win-win solution for everyone.

In the case of Earth to orbit spaceflight, the problem isn’t distance traveled, the problem is the amount of speed the rocket needs to achieve to reach orbit. Since it isn’t possible to place a refueling station halfway up, the only other option is to reduce the amount of speed the launch vehicle needs to achieve to reach orbit. This can be done by adding speed to the launch vehicle at both the beginning and the end of its flight to orbit using externally applied power. This will significantly reduce the amount of propellant the launch vehicle needs to carry, which will allow it to carry more payload.

This is what a Combination Launch System does.

A combination launch system adds velocity to the launch vehicle at the beginning of its flight to orbit using either a catapult,

or by air launching the launch vehicle from high in the atmosphere with a carrier aircraft.

The combination launch system also adds velocity to the launch vehicle at the end of the flight with a non-rotating skyhook.

The end result is that the launch vehicle only needs to carry the propellant for the increase in speed that occurs in the middle part of the flight. The total amount of speed supplied by a mature combination launch system represents up to 1/3 or more of the total speed required for reaching orbit. This reduces the take-off weight to payload weight ratio of the launch vehicle from 200:1 down to 20:1 or less.

This will also allow the launch vehicle to be built as a 100% reusable single-stage vehicle that is much smaller in size than existing launch vehicles.

For example, the Falcon 9, which carries 6,000 pounds of usable payload to the International Space Station, has a take-off weight of 1.2 million pounds. A launch vehicle that is flown as part of a mature combination launch system that has the same payload capacity will have a take-off weight of approximately 120,000 pounds.

An example of what such a vehicle might look like is the X-24C that was designed by Lockheed back in the 1970s.

(photo from fantastic-plastic.com)

In addition, due to its smaller size, lack of drop off components, and complete reusability, this launch vehicle will also be able to make up to 6 flights per day to the skyhook when the skyhook is in an equatorial orbit.

It is the total of these changes that will reduce the cost of getting to orbit down to an amount that anyone can afford. It is the total of these changes that will also allow us to finally start building orbiting hotels and orbital industries on a commercial basis.

But this is not all.

It takes more than affordable Earth to orbit transportation to build a spacefaring civilization. Many of the astronauts have described low Earth orbit as barely skimming the cloud tops. Others have described it as Earth’s doorstep.

To truly step out into the solar system and build a real spacefaring civilization, it will also be necessary to make Earth orbit to escape velocity spaceflight affordable to everyone. Fortunately, the upper end of the non-rotating skyhook makes this possible. Just like the lower end of the skyhook that moves at less than orbital velocity for its altitude, the upper end of the skyhook is moving faster than orbital velocity for its altitude. This allows a spacecraft that releases from the upper end of a suitably long skyhook to be given a boost to escape velocity without using any of its onboard propellant. This reduction in propellant will reduce the size and cost of a spaceship for traveling to the Moon, Mars, and the asteroids to an amount that just about anyone can afford to use. This is what will make Moon bases and cities on Mars both affordable and possible. This will also make asteroid mining possible. Once we have affordable access to lunar materials and the asteroids, building space colonies will also become possible.

In short, a combination launch system is like the transcontinental railroad that opened up the American West. Once it is built, it will open up the solar system for settlement and development and allow us to finally start building a real spacefaring civilization.

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Opening the High Frontier

Opening the High Frontier – When is it going to Happen?

When will we finally have orbital industries, space hotels, and spaceports where anyone can buy a ticket to the high frontier?

I grew up with the space program and these are questions I have asked myself many times over the years. In 2018 it will be 50 years since Apollo 8 flew around the Moon and 46 years since anyone has gone further than low Earth orbit.

Compared to all the dreams of space that we have all read about and seen in movies, the last 45 years appear fairly boring by comparison. Yet if viewed from a historical perspective our slow rate of progress is pretty much the norm. After all, it took over 100 years after the discovery of the Americas before the Jamestown colony was founded on the east coast of North America.

The reason for the delay was the lack of a compelling economic reason to go there. It lacked the weather for growing sugar and it lacked the gold and silver of Central and South America. On top of that, it was far away, the cost was high, and the risk was great. This is also why we stopped going to the Moon. There was no compelling economic reason to go there, it was far away, the cost was high, and the risk was great. Like it or not, this also applies to going to Mars or the asteroids.

Fortunately, compelling economic reasons change with the cost of transportation. An activity that produces a product that is worth $1,000/lb is not going to be profitable if it costs $10,000/lb to ship it. Yet that same product will be very profitable if the shipping cost is reduced to $100/lb. This is what a Combination Launch System makes possible. It lowers the bar on what constitutes a compelling economic reason.

But transportation costs and compelling economic reasons are not the only issues. Another concern is the buy-in cost, the amount of investment that is needed to start a project. The larger the buy-in cost the more difficult it is to earn that money back. In other words; a large buy-in cost requires a product that everyone is going to want and that has enough total profit in it to pay for the initial investment and then some. If the projected total profit for the product is not enough to repay the buy-in cost, there will not be many people who will be willing to put up their money to start the project.

An example of this is the first transcontinental railroad. The first steam locomotive was built in 1803.

It didn’t take long for the economic advantages of this new invention to be proven and for people to realize the incredible wealth that would be generated by building one that would cross a continent. Yet it took over 65 years before the first transcontinental railroad was built.

A big part of the reason for that delay was the size of the buy-in cost. It finally took the US government to fund the first one to get the ball rolling, but after that, the railroads took off on their own.

So how can this information be applied to assist in opening the high frontier?

Compelling Economic Reasons

There are 4 immediate compelling economic reasons for making spaceflight more affordable.

to serve the existing launch market (commercial satellites, military satellites, NASA, and the International Space Station)
to reduce the cost of the planned Outpost Space Station program
space tourism
zero-g manufacturing

After those have been addressed there are:

return to the Moon for water, raw materials, and regolith for shielding
asteroid mining for strategic materials for Earth and for additional raw materials for the zero-g industries in Earth orbit

Are these reasons enough? While most pro-space people would say yes, it is the opinion of the people in charge of NASA, our leaders, and the people who have money to invest that count the most.

Buy-in Cost

The buy-in cost for building a combination launch system is a 200 km long non-rotating skyhook, a reusable Mach 6 X-15 style first stage, a reusable upper stage rocket, and a reusable spacecraft. The only new technology on this list that hasn’t flown before is the non-rotating skyhook. As a result, it might be necessary to fly a skyhook flight experiment on the International Space Station and dock some unmanned suborbital spacecraft at the lower end before starting to build the full-size 200 km long skyhook.

In dollar terms, the buy-in cost for all these items should be in the neighborhood of $2 billion assuming they are all built by commercial companies working on fixed price contracts. Since all of these items will be profitable for the owner/operators, it should also be possible to build all of them as joint government/industry programs which will further reduce the buy-in cost.

Politics

Dealing with politics is probably the most difficult part of starting any space project as there are so many factions in the space community with so many different and opposing positions. Considering how long these groups have been competing with each other, it is also unlikely that they can be enticed to finally start working together. More likely, it will take someone in a leadership position at NASA, in the government, or someone who has the funds to make a decision to build it.

So what would entice someone to make such a decision?

The answer to that will most likely be a combination of both stick and carrot. The carrot being all the economic advantages, the stick being the fear of someone else building it first.

The reason for that fear is that there is room for only one skyhook around a planet. That is because the skyhook will be constantly changing its orbital altitude and its orbital eccentricity in the process of launching and receiving spacecraft at both the upper and lower ends of the skyhook. This constant change of orbital altitude, position, and period would lead to a collision between multiple skyhooks. This means that whoever builds the first one will end up controlling access to the high frontier. Whoever does that will also establish the political and social standards for the spacefaring civilization that will come into being as the result of affordable access to space. In addition, the wealth brought home by those space activities will make the country that controls the skyhook the wealthiest nation on the planet. I suspect that the only way to keep the peace with this will be to build the skyhook as part of a multi-national program as was done with the International Space Station. It won’t be an easy sell.

In Conclusion

Writing the book Opening the High Frontier, this blog, the video, the other websites [1] [2], and presenting this idea at conferences has been a very interesting experience. The growing level of interest as shown by the increasing number of people who read these sites, buy the book, as well as the interest and comments at the conferences, is both enlightening and gratifying. I have no doubt at this point that a combination launch system with non-rotating skyhook will be built someday. The only remaining questions are who will do it, and when they will do it. As to the when, I hope soon as I would dearly like to use it. As to the who, that is anybody’s guess. While I hope it is the United States that takes the lead in building this, I can’t help but notice in the website statistics that there are a growing number of people from all over the world who are reading about this. I hadn’t realized just how much interest there is in the idea of building a spacefaring civilization by people from all around the world. I hope all of you who read this will consider writing a letter to President Trump and tell him of your support for making this happen. It can’t hurt and it just might help speed things up.

Ad Astra!

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New Worlds Conference, 2017

I just finished presenting the Combination Launch System concept at the New Worlds Conference in Austin Texas. The conference was really fun with a lot of great presentations, some potentially world-changing ideas, and a lot of really wonderful people.

The Combination Launch System concept also received a tremendous amount of interest and questions as well as many very positive comments by some very important people as a result of that presentation. My thanks to all who were there for your interest, questions, and comments. It has been a lot of work to create and validate this concept, write the book and put together the presentations, so it is truly gratifying to see people understanding and getting the value of it. I hope all of you will share this idea with everyone you know so that we can get it built.

The Combination Launch System concept is the real deal. It can be affordably built with existing materials and technology, and it will open the high frontier for settlement and development to everyone who has the dream and desire to go there. All that is missing is communicating the idea to enough people so that we can get it built.

The need for a Compelling Economic Reason

One statement that was repeated many times by the business people and venture capitalists at the New Worlds Conference was the need for a compelling economic reason to invest the money for building a more affordable launch system for any space activity. No one is interested in financing a project of this magnitude without the ability to recoup that investment and make a profit. As Robert Heinlein once said, “There is no free lunch.”

Sending people to Mars to build a settlement is not enough of a reason to justify that investment. There needs to be something on Mars that will justify the risk and payback the cost. Something like the gold rush that drew people to California in the 1850s. The same applies to going to the Moon, the asteroids, or building a space colony. There needs to be a compelling reason that is worth all the effort that can’t be obtained for a lower cost on Earth.

The Outpost Space Station

One possible justification for such an investment is when that investment will reduce the cost of an already planned project by more than the cost of the addition. An example of this is the Outpost Space Station that NASA wants to assemble out near the Moon. The cost of launching all the pieces of the Outpost Space Station into orbit, boosting them to escape velocity, and then placing them in orbit at either L1, L2, or around the Moon will be extremely expensive. Sending crews, supplies, and spare parts to it will also be extremely expensive. Building a Combination Launch System to help launch the pieces of the Outpost Space Station into orbit and to escape velocity, as well as for sending crews and supplies to it once it is in position near the Moon, will reduce the cost of the Outpost Space Station program by more than it will cost to build the Combination Launch System. It is a win-win situation that justifies the investment to build the Combination Launch System and makes the Outpost Space Station much more affordable. Also, since the Combination Launch System will make money for its owners, it will also be possible to build every component of the Combination Launch System as a joint government/industry project. That will further reduce the cost of the program.

Think about that for a bit. The Outpost Space Station with Combination Launch System could become the modern-day equivalent of the transcontinental railroad that connected the East Coast with the West Coast and everything in between. Only, in this case, it will connect the Earth with low Earth orbit, lunar orbit, and the Earth-Moon Lagrange Points. It will also allow affordable access to the lunar surface and near-Earth asteroids on a regular basis once the spacecraft for those missions are built.

In addition, the Combination Launch System will make Earth to orbit transportation so affordable that it will allow the commercial development of low Earth orbit with orbiting hotels for space tourism as well as orbiting industries for zero gravity manufacturing and spacecraft assembly.

It will be the true birth of a real spacefaring civilization.

Once this is all in place it will only be a matter of time before spaceships will be going to Mars and the asteroids.

Those spacecraft will be followed by space colonies in cislunar space and in orbit around Mars

And it all starts with a Combination Launch System.

We are that close.

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Starship Congress 2017, Combination Launch Systems

How a Combination Launch System Works

A combination launch system works by reducing the total speed a launch vehicle needs to achieve in order to reach low Earth orbit. For a launch vehicle to reach low Earth orbit on its own without the assistance of a combination launch system, it needs to accelerate to a very high apparent velocity. In addition to achieving the actual speed of low Earth orbit (7,800 m/s), it also needs additional speed to overcome the force of gravity that is working to pull it down as it boosts for orbit and even more speed for overcoming the aerodynamic drag that wants to slow it down. There are also other issues that require additional speed to overcome but these are the three largest. It is the total of all these speeds that are known as the apparent velocity, or the total speed required for orbit. When all of these speeds are combined together, the total amount of speed required to reach low Earth orbit when launching due east from Cape Kennedy is approximately 9,100 m/s. This is the total speed required for orbit.

For a launch vehicle to reach orbit and do it affordably it also needs to be single stage, completely reusable, and carry a large enough payload to make it all worthwhile. Unfortunately, it is not possible to build such a launch vehicle with current technology. The reason for this is the amount of propellant that it takes to get to low Earth orbit using chemical rocket motors. Using the highest performance chemical rocket motors available, a Single Stage To Orbit launch vehicle would need to be 87% propellant when it leaves the launch pad. That leaves only 13% for the launch vehicle and payload. That is not enough to make a Single Stage To Orbit launch vehicle completely reusable and still carry enough payload to make the cost per pound to orbit mass market affordable.

The closest we have come to building such a launch vehicle was the partially reusable Two Stage To Orbit Space Shuttle. It had a propellant fraction of 87.2%, an empty weight fraction of 12%, and a maximum payload fraction of 0.8% when flying to the International Space Station. It was also significantly more expensive to fly than any expendable launch vehicle.

This is where the combination launch system with non-rotating skyhook comes in. The first step of a combination launch system consists of either

an air-assisted launch

or a ground assisted launch.

A subsonic air-assisted launch using a carrier aircraft like Stratolaunch will reduce the total speed required for orbit by approximately 1,100 m/s. A 600 MPH ground assisted launch from a mountain top will reduce the required speed for orbit by approximately 900 m/s. An air-assisted launch will require the addition of wings to the launch vehicle. This will increase the empty weight of the launch vehicle as well as the drag. A ground assisted launch does not require this. The end result is they are both about the same when it comes to reducing the total speed required for orbit. Reducing the total speed required for orbit by 900 m/s will reduce the necessary propellant fraction from 87% to 84%.

If it is assumed that a fully reusable single stage launch vehicle requires an empty weight fraction of 15% to be built (3% more than the empty weight fraction of the Space Shuttle, or a 25% increase in empty weight), then either of these assisted launch concepts will make this kind of launch vehicle possible but the payload fraction will still be only 1%.

If it is assumed that a fully reusable single stage launch vehicle will reduce the cost to orbit by 90% compared to existing expendable launch vehicles, then this system will reduce the cost to orbit to approximately 1/10th of what it is today.

If this reduction to the propellant fraction is used to increase the payload fraction from 1% to 4% and the launch vehicle is left unchanged, then this system will reduce the cost to orbit to approximately 1/4th of what it is today.

Either approach will work, but neither of them by themselves will make spaceflight affordable to everyone.

Now add the non-rotating skyhook to the launch system. One design for a mature non-rotating skyhook has an overall length of 2,200 km and a lower endpoint velocity of 80% of orbital velocity for its altitude. This will reduce the total speed required for the launch vehicle by 1,560 m/s. Combine this with the 900 m/s velocity reduction that comes with a ground assisted launch and the total speed required for flying to the lower end of the skyhook becomes 6,640 m/s. If it is assumed that the same high-performance LOX/LH2 rocket motors are used, the required propellant fraction will drop from the original 87% to 77%. If it is also assumed that the fully reusable Single Stage To Skyhook launch vehicle can be built with an empty weight fraction of 15%, the payload fraction becomes 8%. This is 10 times the payload fraction of the Space Shuttle when it flew to the International Space Station. Now, keep in mind that this launch vehicle is a fully reusable Single Stage To Skyhook vehicle that is expected to cost 1/10th the amount to fly as any expendable launch vehicle and combine this number with the 10 fold increase in payload. That works out to 1/10th divided by 10 = 1/100th the cost in dollars per pound to orbit of any expendable launch vehicle flying to orbit without the assistance of a combination launch system. In other words, if the original expendable launch vehicle cost $10,000 per pound to orbit, the fully reusable Single Stage To Skyhook vehicle will cost somewhere in the neighborhood of $100 per pound.

If an empty weight fraction of 15% is not enough to build a fully reusable Single Stage To Skyhook launch vehicle, increase the empty weight fraction to 18%. That is 50% more than the empty weight fraction of the Space Shuttle. This will reduce the payload fraction to 5% and increase the cost of flying to the skyhook to $160 per pound. To get back to the $100 per pound launch cost it will be necessary to increase the length of the skyhook until the lower endpoint velocity is moving at 73% or orbital velocity for its altitude. This will reduce the propellant fraction of the launch vehicle to 74% and increase the payload fraction back to 8%.

This $100 per pound launch cost is what most people think of as affordable to everyone spaceflight. Think about that. If the seat weight per passenger is 200 pounds, that means the price for a ticket to the lower end of the skyhook will be in the neighborhood of $20,000. How many people would buy a ticket to fly to the lower end of the skyhook for that price? Would you?

What the view from the lower end of a skyhook will look like.

Impact on Lift-off Weight

Another issue that doesn’t get discussed very often is how the combination launch system and non-rotating skyhook affect the lift-off weight of the launch vehicle. Existing launch vehicles are large and that adds to their cost. The Space Shuttle had a lift-off weight of over 4.4 million pounds. The Falcon 9 has a lift-off weight of over 1.2 million pounds. The largest Delta launch vehicle has a lift-off weight of 1.6 million pounds. By comparison, the Boeing 737 MAX airliner has a take-off weight of 195,000 pounds. As the old saying goes, size matters, and it has a direct impact on cost.

What determines the lift-off weight of a launch vehicle is its payload fraction and the size of the payload that needs to be delivered. If the design payload size for a conventional launch vehicle along the lines of the Atlas or the Delta is 12,000 pounds, and the payload fraction for the launch vehicle is 1%, then the lift off weight will be 1.2 million pounds. If the design payload size for a fully reusable Single Stage To Skyhook launch vehicle using the previously mentioned ground accelerator and skyhook is also 12,000 pounds and it has a payload fraction of 8%, its lift off weight will be 150,000 pounds. That is 1/8th the lift-off weight of the conventional expendable launch vehicle and on top of that, it is fully reusable. It is also worth noting that its lift-off weight is less than the take-off weight of the Boeing 737 MAX.

Now notice the empty weight. If the empty weight fraction is 15% its empty weight will be 22,500 lbs. If the empty weight fraction is 18% its empty weight will be 27,000 lbs. By comparison, the empty weight of the Space Shuttle Orbiter was 172,000 pounds. Either way, imagine how much easier it will be to move the Single Stage To Skyhook vehicle around, to service it, and to prep it for flight.

When it comes to cost, smaller is definitely better.

What an air-launched fully reusable Single Stage To Skyhook launch vehicle might look like.

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Combination Launch Systems, Presentation

For those of you who live in or around Monterey, California, I will be giving a presentation on Combination Launch Systems at the Starship Congress August 7-9, 2017, at the Hyatt Monterey Regency.

If you can make it, stop by even if only for an afternoon! It will be great fun!

Eagle Sarmont

_______________________________________

August 18, 2017

The Starship Congress was great fun with lots of interesting ideas, projects, and people. Unfortunately, no one presented a working prototype of either a warp drive or an anti-gravity drive, which means we are stuck with reusable rockets and combination launch systems for the forseeable future.

On the plus side, my presentation on Combination Launch Systems received rave reviews from just about everyone who saw it, both at the conference and on the live feed that was broadcast on the internet. Here are two tweets that were forwarded to me as a result of that presentation.

Space elevator.@StarshipCongrss pic.twitter.com/v6D1f6tMtd

— Juan Díaz Infante (@JuanDiazInfante) August 10, 2017

Good to know for people looking for designers who design for space ? Eagle's lunar elevator presentation won over entire conference? https://t.co/GMR4yYrIkT

— Starship Congress (@StarshipCongrss) August 10, 2017

It has not been easy to figure out how to communicate the combination launch system and non-rotating skyhook concepts to non-aerospace people due to both of these ideas being so different from other launch vehicle concepts. It usually takes a good understanding of basic orbital mechanics and Tsiolkovsky’s rocket equation before the significance of these concepts becomes clear. The high percentage of very favorable responses to this presentation tells me that I am finally on the right path for communicating that. Even so, based on a couple of after conference comments, there were still at least two people at the conference who did not get the significance of what $100 per pound to orbit launch costs will mean to the opening of the high frontier for settlement and development.

Currently, it costs over $22,000 per pound to launch supplies and cargo to the International Space Station using the Falcon 9 rocket and unmanned Dragon spacecraft. That number comes from the NASA/SpaceX Commercial Resupply Services contract that consists of NASA paying SpaceX $1.6 billion for 12 cargo resupply flights to the International Space Station. That works out to $133.3 million per flight. The maximum useful payload delivered by one of those flights was reported to be 2,708 kilograms or 5,970 pounds. That comes out to $22,200 per pound of useful payload delivered.

Even if the $62 million per flight cost of flying a basic Falcon 9 rocket without the Dragon spacecraft is used, the cost of flying to the International Space Station would still be $10,300 per pound.

Now think of that cost in terms of your everyday activities such as the food you eat, the water you drink, and the air you breathe.

Now think of it in terms of the cost of launching the computer you are using to read this, of the cost of launching a spacesuit should you need to go on an EVA, and of the cost of launching a habitation module for you to stay in and work in while you are at the International Space Station.

Now think of that cost it in terms of building a spacecraft for going to the Moon, or building the pieces of a modular Moon Base that will need to be lifted into Earth orbit and then sent to Lunar orbit and finally soft landed on the Moon. How many tons of materials will be needed in Earth orbit to do that? Now multiply that figure by $10,000 per pound.

If you think $10,000 per pound to orbit is too much, use $5,000 per pound or $3,000 per pound, the total cost will still be way too much to allow us to start building a spacefaring civilization.

This is why we do not have a base on the Moon. This is why we have not built a spaceship for going to Mars. This is why we have not built space colonies or satellite solar power stations. This is why we do not have space hotels and spaceplanes for carrying tourists into Earth orbit.

For someone to say that the cost of spaceflight is not the single most important issue limiting our activities in space tells me that that person does not understand the problem.

Yes, there are other issues that need to be solved such as closed loop life support systems, and how to deal with the long term effects of either reduced gravity or zero gravity. There are also questions about how to protect astronauts from solar and cosmic radiation, and developing the technology for using lunar and asteroidal materials in order to live off the land, but solving all of these problems won’t matter if we can’t get the cost of getting off planet down to an amount that people can afford to pay.

In closing, I would like to say a special thanks to those of you who “liked” those two tweets. The amount of work that has gone into developing and validating the combination launch system and non-rotating skyhook concepts has been huge and it is very gratifying to see people starting to see the value of them.

Thank you.

To read the conference paper “Combination Launch Systems” that went with my presentation, go here.

One last thing. The people who put together the Starship Congress are currently processing the videos for all the presentations and will start uploading them to the internet as soon as they are completed. I will include a link here to my presentation as soon as it is available.

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