🚓 💅 🖕🏿 SLS vs STARSHIP: Why do both programs exist? Everyday astronaut 📞 🧗🏼 🤴🏿

MAY 1, 2020, TIM DODD, EVERYDAY ASTROUNAVT
WEB VERSION: FLORIAN KORDINA AND JOEY SCHWARTZ

A few words from me why and why.
I like the American space journalist - Tim Dodd. For his enthusiasm and meticulousness when considering the topic. You can be critical of his assessments and conclusions, but his materials are interesting and always cause resonance. But very, very large in size. Adapted google translation of his new article (released to the video of the same name). For all the jambs of such a translation (I apologize in advance for this) it is better to read the primary sources than retellings with censorship and distortions and, sometimes, without mentioning the author.

A video released by Everyday Astronaut this week talks about SLS and Starship. The video and this article describe how they relate to NASA’s plans to return to the moon by 2024.

The video on which NASA

INTRODUCTION
is written has
just announced its selection of lunar ships for the Artemis program. To everyone's surprise, the huge Starship SpaceX was one of the three spacecraft chosen by NASA along with Blue Origin and Dynetics.

It is clear that this raises many questions. We will answer some of them in my next video / article: “Should NASA just cancel the SLS and use Starship and / or other commercial launch vehicles for Artemis?”

But first, I think, we need to consider a lot of controversial issues about these two missiles. Now, more than ever, it's time to truly compare them directly with each other.

WHY TWO MEGA-ROCKETS?

This can go into history books as a historical curiosity that these two missiles existed simultaneously. Despite the fact that they have very similar capabilities, you will not be able to come up with more opposite options. The embodiment of two fundamentally unique engineering approaches.

Boeing and NASA have been building their project over the years with experienced rocket scientists. In contrast, Starship is being built on a field in Texas by a "diverse team of space cowboys." Some of which previously built water towers.

HOW TO COMPARE THESE ANIMALS?

Let's take a look at the history and development of Starship and SLS today. In addition, we consider the Orion spacecraft and everything else necessary for the missions of Artemis, including their design features and capabilities.

As soon as we do this, I think we can answer the question. How is it possible that two rockets, such as SLS and Starship, exist simultaneously? Should they exist simultaneously? Moreover, one of them is the most ambitious rocket ever conceived. And another project lives on in the past. This is a literal reuse of old parts from the era of "space shuttles."

How did we end up in this situation? The two most powerful missiles ever made, and they go out into the world at the same time. We have something to tell about this. Let's start.

WHAT IS AN EXTRA HEAVY CARRIER?

You guys know me. As soon as I got into the topic of “SLS vs Starship”, I got too carried away answering my questions. I delved deeply into the subject and changed many of my assumptions in which I was mistaken. And everything that “cooked”, we will consider in detail and deeply! This is madness!

NASA AND SPACEX ARE NOT COMPETITORS!

Immediately, we need to clarify one thing. NASA and SpaceX are not competitors. If you love SpaceX, you can thank NASA for this. NASA is SpaceX's largest customer and their largest supporter. Remember this.

This has become very obvious now than ever before, after the start of NASA's Starship investment in the Artemis program. Proof of this may be the NASA logos throughout the SpaceX Falcon 9 rocket for the Commercial Crew mission. It is worth remembering that the relationship between NASA and SpaceX has continued since the founding of the company.

SpaceX 'Falcon 9 with NASA retro logo on its side. This particular rocket is for the DM-2. (Courtesy: NASA)

If it weren’t for NASA’s initial investment of about $ 400 million for the Falcon 9 and Dragon spacecraft, SpaceX would not exist now. Plus, the multi-billion dollar CRS and Commercial Crew contracts have helped SpaceX rise to where they are today.

NASA is doing incredible things. They are engaged in vital research and science that no private company could and could not do. They do a lot “behind the scenes,” things that often go unnoticed. In my previous video comparing SLS and Starship, I explained why it is unfair to compare NASA, as an organization, directly with a private SpaceX company.

LET'S DO IT TOGETHER!

As you guys know, I'm mostly for teamwork. I like to encourage my audience to fight tribalism, and not just think that one is better, and everything else sucks. But given how NASA builds and operates rockets, we can correctly compare the pros and cons of these two systems. I already know that for many of you, the “Orange Rocket” is “bad,” and the “Brilliant Rocket” is “good,” or vice versa. So let's get together, sing Kumbaya and just accept the fact that we have some mega-missiles!

DEFINITION OF AN EXTRA HEAVY CARRIER

Now that the emotions are gone, let's define the term Super Heavy Class Booster (SHLLV). I just wanted to explain why we didn't include missiles like the upcoming New Glenn from Blue Origin or other heavy launch systems in this comparison. The aerospace industry sees SHLLV as a rocket that can launch more than 50 metric tons into low Earth orbit (LEO).

Superheavy launch vehicles can launch even heavier objects into orbit. This means that they have the ability to send potentially huge devices to the moon. Or they are able to send interplanetary vehicles along direct trajectories to objects of the solar system without traditional gravitational maneuvers. This means that flying to distant objects of the system will be three times faster!

ALL SHLLV ROCKETS: PAST AND PRESENT.

Historically, there were only five super-heavy missiles built for flight. And only four launch systems were successful in flight. This is a 1960s American Saturn V booster rocket that could lift 140 tons on LEO. Also in the 1960s and early 70s, the Soviet Union had an unsuccessful N-1 booster rocket designed to launch 95 tons on the LEO. In the 1980s, the Energia launch vehicle, which could launch 100 tons on LEO, was also launched twice in the Soviet Union.

To date, the only SHLLV flying rocket is the Falcon Heavy from SpaceX. Officially, it can withdraw about 64 tons on a single-use LEO. If run in reusable mode, it can still output more than 50 tons on LEO. Until now, the Falcon Heavy did not need to fly in a one-time option, and this may never be required.

STS SPACE TRANSPORT SYSTEM: SPACE SHUTTLE PROGRAM

And finally, we had the Space Shuttle “space shuttle” —or, as NASA officially called it, the Space Transport System (STS). If we add an orbiter as part of the payload, technically the STS can put 122.5 tons into orbit. Now we must indicate that following this logic, if you turn on, say, the basic SLS stage, which can go into orbit if you want to, it will add another 80 tons to its payload.

But STS was just another “beast,” and you should consider the orbiter as a payload that went into orbit, but the actual payload was only 27 tons. While there was a Shuttle-C proposal to make STS an extra-heavy launch system, we will ignore it and continue.

If people want to return to the Moon as soon as possible, or, especially, if we want to get to Mars, we absolutely need serious opportunities to put them into orbit. I think that the time has come for such missions. I want people to the moon again! In 4k! Or 8K, which is even better! Send MKBHD there!

ARTEMIS AND GATEWAY PROGRAMS

Before we begin to learn the facts about SLS and Starship, we will consider returning to the moon using NASA's Artemis program. NASA has already completed a significant amount of work, allocated funds and set goals for turning Artemis into a real program.

In this article, you will also hear how Artemis is often “scattered” without measure. We could combine the future Gateway lunar space station with Artemis. Instead, we confine ourselves to considering SLS, Orion, and Human Lander Systems. To make it clear, Artemis is for SLS, like Apollo was for Saturn V. This is the name of the program, not a rocket or spaceship.

Currently, the Gateway is not intended for the first or two first missions, which are planned for the landing of astronauts on the lunar surface. Although the construction of the Gateway is planned for future missions, we will simply focus on flying to the moon and on equipment directly related to this.

HISTORY OF SLS AND ORION

We will tell you some facts right before we push these two missiles head-on! First, I think many people have a misconception about how and why NASA developed SLS and Orion. Or how these programs fit into Artemis’s plans. Secondly, we will move on to the history of Starship with its rapid development.

POST-COLOMBIAN TRAGEDY, CONSTELLATION PROGRAM

After the tragedy of the Columbia spacecraft (Colombia), NASA revised its future plans. The search began for a replacement of low-orbit means of access in the Space Transportation System program. NASA changed its priorities for deep space exploration, and for this they needed to build a large rocket.

NASA's original plan for deep space and LEO was the Constellation program. Ares I manned spacecraft replaced Shuttle in missions with LEO. NASA has planned an even larger rocket called Ares V for its moon and Mars exploration missions. After slow progress and huge cost overruns, as indicated in the 2009 Augustine Commission report, the Constellation program was closed.

The Ares-1X rocket takes off on October 28, 2009. (Source: NASA)

SLS: SPACE LAUNCH SYSTEM, AKA “Senate Launch System”

The 2010 NASA Authorization Act instructed NASA to develop the Space Launch System (“Space Launch System”). She was supposed to raise from 70 to 100 metric tons on LEO, and later - up to 130 tons or more. The booster should be able to lift the Orion Crew manned spacecraft as its development continued, and Congress demanded that NASA work with existing partners who are already working on the topic.

Initially, NASA hoped to quickly and efficiently launch a superheavy rocket, as required by a directive from Congress. They were supposed to fly before December 31, 2016! NASA performed an analysis of the project’s quality indicators and reduced it to five different launch vehicle options. Some of them looked spectacular, with diameters of the base stage of ten meters and a two-stage engine with oxygen-enriched generator gas afterburning. The analysis was carried out according to the following criteria: feasibility 55 percent; work schedule 25 percent; 10 percent payload and 10 percent software.

Comparison of what would be an Ares V rocket and SLS. (Source: NASA)

SLS WITH HERITAGE STS

NASA settled on the option now known as SLS. Although SLS and Ares V look very similar, SLS was actually a fairly new design. This was definitely related to an early rocket offering called Direct. SLS made the most of the remaining parts and facilities (literally) from Space Shuttle. Their speculative approach was that such an approach should facilitate the rapid prototyping and testing of the most powerful rocket ever created.

NASA tried to bring the project as close as possible to the previous Space Transportation System. Thus making happy some contractors, their employees and members of Congress. This design decision guaranteed (or so assumed) that funds would continue to flow to Shuttle contractors.

CONTRACT "COST-PLUS"

Unlike the Commercial Crew, NASA will continue to work with Space Shuttle contractors using a cost-plus financing scheme. In practice, this means, "That's how much money we will give you to do this, but we will also pay bills for anything that goes beyond the budget."

Funding for the development of SLS has been around $ 1.5 billion per year since 2011. The Orion spacecraft receives a little over $ 1 billion a year, also since 2011. NASA assured contractors that they will have enough resources to implement these projects. Contractors remained within the framework of NASA's realistic budget, which corresponded to NASA funding levels in the Space Shuttle era.

Nevertheless, the problem associated with the conclusion of contracts with payment of costs is that they have very little incentive to remain on the budget and adhere to the work schedule. In fact, “slipping” a work schedule literally means more money for contractors. The main SLS contractor, Boeing, receives the most money from the project. NASA periodically reviews the performance of its contractors. However, government officials are still scolding NASA for treating some of these contractors too easily. More about this later.

LIKE SLS WITH SHUTTLE EXTERNAL ONLY

Although the SLS literally looks like a giant wingless “space shuttle”, NASA has made many changes to the design of the rocket. For example, they increased its carrying capacity and reduced costs. Here is a summary of the changes.

The SLS will have SRBs (side solid fuel boosters) with five segments, as opposed to the four-segment SRBs that the STS had. Unlike Space Shuttle, these boosters lack reusability. They have a different design of joints, which does not allow gases to escape during flight. The redesign ensures that debris does not damage the nozzles of the nearby RS-25 engines.

Solid Rocket Booster (SRB) for SLS during the test. Fragments flying around is a newly developed cork. (Source: NASA)

The base stage looks like an external Space Shuttle fuel tank. In addition to appearance, it has practically nothing to do with the external Shuttle tank, except for its color and diameter of 8.4 meters. A new material is used - AL 2219 aluminum. The design itself is different from Shuttle's external tank. Various welding methods are used, and even a new sprayed thermal insulation. The SLS will be designed with load distribution applied to the top of the tank and to the sides of the tank.

Aerospace-Rocketdyne finalized the RS-25 engines used in the STS program. They increased power output from 104.5 percent to 109 percent, or 111 percent in an emergency. At the same time, as for SRB, RS-25D, and then available RS-25E options, can be used in SLS.

Just a fun note, I base these percentages on an initial nominal thrust of 1.6 MN (375,000 pounds of force) at sea level. After some changes in the main engines, they were able to go beyond their original design parameters for the Shuttle program. For SLS, they were upgraded to great power.

INTERMEDIATE CRYOGENIC UPPER STAGE

Another solution, which helped save money and reduce time, was to first use SLS with the upper stage from the Delta IV and Delta IV Heavy ULA. NASA has modified the Delta Cryogenic Second Stage (DCSS) so that it mechanically matches the top of the base stage with a diameter of 8.4 meters. This Interim Cryogenic Propulsion Stage (ICPS) has hydrogen tanks of a different design and more fuel than the Delta IV version.

Interim Cryogenic Propulsion Stage (ICPS) ULA for SLS.

NASA plans that the SLS will have a much more powerful upper stage in the future, known as the Exploration Upper Stage. The upgraded stage, which is part of the Block 1B update, will make the SLS much more load-bearing. Although this design will not see the light until 2025.

Comparison of ICPS and EUS. (Source: NASA)

ORION SPACE SHIP. APOLLO ON STEROIDS?

Next we need to talk about the Orion spaceship (Orion), which is located on top of the rocket for missions Artemis (Artemis). Orion is a traditional conical shaped manned ship. In a sense, this is a newer and more advanced version of the Apollo command module.

Parallel comparison of command and service modules Orion and Apollo.

Although Orion looks similar, it is bigger than it might seem. In fact, it is a spacious vehicle with a diameter of five meters compared to the diameter of the Apollo command module of 3.9 meters. Orion also has a whopping 9 cubic meters of pressurized volume compared to 6.2 cubic meters of Apollo. This allows the Orion spacecraft to accommodate up to six astronauts compared to a regular crew of three Apollo astronauts. It is worth recalling Skylab for which the Apollo command module was changed so that it could accommodate five astronauts in an emergency.

The original name of the Orion spacecraft was the Crew Exploration Vehicle (Manned Research Vehicle). That is what he was called in development for the Constellation program. But since then it has changed. Now it has implemented yet another cost-saving measure: it uses a service module based on the European ESA Automated Transfer Vehicle.

LUNAR LANDING VEHICLE? ANYTHING?

There is one more thing that we should mention. Something new for a system that is still under development. If the Artemis program is to moon on the moon, it will need a lander.

This brings us to the current situation. So far, everything we talked about and discussed was for putting people into lunar orbit only with the help of SLS and Orion. Without the ability to install an additional lunar lander on SLS Block 1 as part of the overall package when flying to the moon. This is not possible even with the upgraded Block 1B.

NASA officially selected three completely different lunar ships for the Artemis program. Each of the applicants has time until 2021 to accurately demonstrate how they will get to the moon. Moreover, some offers can send lunar modules together with Orion on the updated SLS Block 1B.

In order for the Artemis III mission to reach the moon in 2024, it will have to use SLS Block 1. The lunar lander will have to fly one or two commercial missiles. Maybe even three? It will depend on how big it turns out. Atremis hardware is huge by modern manned flight standards.

CALL FOR COMMERCIAL LANDING DEVICES

This part of the Artemis program is closer to the Commercial Crew program than to the rest of the SLS and Orion programs.

NASA has developed a number of requirements for contractors to bid on moon landing contracts. At the same time, they hope that this will be a quick process to meet their ambitious deadlines - by 2024 to deliver astronauts to the moon. NASA will not own and control a spacecraft, as they do for SLS and Orion.

Artemis will need at least two missiles per mission with a crew landing on the lunar surface. We will consider the options proposed in the Human Lander Systems program in the second part of this article. Consider what other options NASA has if they decide to cancel SLS in favor of Starship and other commercial offerings. For this reason, let's talk about Starship.

STARSHIP HISTORY

If you are new to Star Wars, you may not understand how far this joke has gone. In fact, since the creation of SpaceX, there has been talk of creating a “BFR” or “Big F * + # ing Rocket”. Unlike SLS, the actual design and development from the first days were mostly behind closed doors.

TOM MULLER, MISSION GUY Guy

Returning to SpaceX, engine engineer and number one worker, Tom Muller, built the BFR rocket engine at his powerful rocket club, the Research Research Society. And yes, this name is taken from the BFG in Doom.

Note that the Tom BFR engine was a pin-injected injector engine that could create a thrust of 45 KN / s. He fought David Chrisally, who built a more traditional flat-injected engine. Tom's design won and eventually became the basis for the modern Merlin engine!

But the BFR rocket did not receive public coverage until around 2012, when Ilon mentioned a huge rocket called the Mars Colonial Transporter, which SpaceX added to its line of future plans.

SpaceX was still a relatively small company, only launching three Falcon 9s by the end of 2012. After that, there were rumors about the Falcon X, Falcon X Heavy and Falcon XX missiles, which will be their next mega-missiles.

MAK-2016, ILON AND ITS ITS

Only in 2016 - at the International Aviation Congress (IAC) in Guadalajara, Mexico - Ilon detonated a “bomb”. The world has finally understood what SpaceX is working on. And yes, it was a super weird press conference where everyone asked ridiculous questions. But not everyone understood ...

The plans presented by Ilon were ridiculous, perhaps even insane. Something that the world has never seen in the form of a practical project. The rocket is fully reusable, 12 meters in diameter, 122 meters high with 42 closed-cycle engines with complete gasification of methane-fired components in the first stage. Six vacuum engines and three more sea level engines on the upper stage. She used an advanced carbon composite hull design and had a load capacity of 300 tons per LEO. We recognized it as the "Interplanetary Transport System" or ITS.

Speech by Ilona Mask at MAK-16

After 2016, we observed design changes from year to year. The biggest change is downsizing. Suddenly, the rocket shrank to a diameter of nine meters, and its payload decreased with size.

Around 2018, SpaceX again began calling it BFR and announced plans to send Japanese billionaire Yusaku Maezawa on a journey to the moon. Meanwhile, perhaps another big change was the decision to abandon the carbon composite body design and use stainless steel instead.

STARSHIP, THREE IN ONE!

Then, finally, the name Starship (Star Ship) appeared. Not to be confused, SpaceX calls the entire Starship system. But this is also the name used for the upper rung! They call the Super Heavy accelerator stage. Therefore, we can freely say Starship, which means Starship and Super Heavy. However, we could also mean only the upper stage.

It’s like you can show the corn and say, “Hey look, this is corn! If it is on the cob or in a plate, you will still call it corn. But when she is on the cob, you can say that it is corn on the cob. " God, you want to say that I'm from Iowa, right?

In 2019, SpaceX held a press conference in front of the full-size prototype Starship in Boca Chica. Later we learned that his name is Mk 1, short for "Mark One." At this point, the design came to the conclusion that the upper stage should have only two "ribs" that act like giant air brakes. I shot a video explaining the reasons why they most likely chose two “fins” instead of three, and it's interesting to watch!

This greatly helped to understand the design of Starship, since most of the actual development was conducted behind the closed doors of SpaceX. I think that now will be a great time to go through the progress of these two programs. Let's put together exactly what they built and see if we can better understand their wildly unique design philosophies.

Video about the fundamental design changes BFR / Straship

PROGRESS SLS VS PROGRESS STARSHIP

This is a piece that I have been thinking about for some time. Starship skeptics will point to all the exploded test prototypes and say, "They can't even build a tank." While the skeptics of the SLS say: "Ten years have passed and nothing happened."

Let's look at all the equipment that was built. This will be a comprehensive but not complete list of absolutely everything. At least we will mark the milestones. Starting with SLS and Orion, the equipment that contractors built and / or tested is much more than you think.

Inventory of SLS and Orion, consisting of test samples and flight equipment.

ARTEMIS I, ORION AND TEST SLS

So far, we have seen more than a dozen Orion used on the Ares 1-X, in various CAC tests, with layouts and landing tests. In 2014, the fully-functional, mainly, flight of the Orion prototype on the Delta IV Heavy in the EFT-1 mission took place. In 2019, in the Space Center. Marshall even tested the full-size SLS hydrogen tank for destruction. The test lasted more than five hours at loads up to 260 percent of the nominal mode exceeded.

All equipment for the first comprehensive testing of SLS and Orion for the Artemis 1 mission is basically ready for final assembly. The base stage is located on the test bench, preparing for continuous static burning of engines. The assembly of five segments of each accelerator SRB will happen soon. The emergency rescue system is ready. The Orion spacecraft has completed all of its trials. He returned to the Kennedy Space Center in anticipation of his upcoming launch around the moon!

The upper cryogenic stage has been ready for operation for several years. The Orion ship service module supplied by EAS is ready. Literally - the equipment for Artemis I is in full! It remains only to complete the testing, and then make the final assembly.

There are 16 RS-25D engines. 14 of the 16 engines previously flew Space Shuttle. They have already installed four engines in the engine compartment of the Artemis I base stage. Enough segments of the solid rocket boosters have been produced to assemble 16 boosters for eight SLS flights. Even 4 RL-10 engines are ready for use in the next stages of the program.

TASKS FOR ARTEMIS II AND III

Now that production lines and assembly sites have freed up, parts for Artemis II are coming together. This includes an oxygen tank, a hydrogen tank, an intermediate tank, a transition upper section, an engine section at the base stage. The tank for Orion, its service module, heat shield, CAC tower and other equipment items are in place. And, as already mentioned, the RS-25 and booster segments are also ready.

That's not all, the Artemis III hardware is also packaged together! This includes Orion ship parts, service module parts, an SLS hydrogen tank, engines, and solid rocket boosters.

So you can see that SLS and Orion have accomplished a lot in the last decade. Even considering the longer development period of Orion. But how does it look compared to Starship progress?

STARSHIP PROGRESS Starship

progress is significantly different from SLS and Orion. Most of Starship’s early development was very closed. They even mysteriously hid the Raptor engine development program until Ilon showed a video about it at MAK-2016.

The development of the Raptor engine began around 2012. Since then, he has passed many tests. To date, 26 Raptor engines have been built, many of which are currently being tested. But, most likely, there is only a handful that is really capable of flying at the moment. This number is changing since SpaceX built most of them only in 2019.

SpaceX inventory of test items, prototypes, and Starhopper.

REAL STEEL

If we ignore everything built from a carbon composite and / or for Starship with a diameter of 12 meters, SpaceX built almost everything that we are going to list only last year. Starting with Starhopper, this single Starship prototype that has advanced in tests. Its 20-meter, and then 150-meter flight is the only prototype flights so far. We saw that the full-scale prototype of the Mk 1 was fully assembled, but then removed the top.

SpaceX simultaneously built a similar prototype in Cocoa, Florida. It was an opportunity for the two teams to work simultaneously on different construction methods in a friendly competition. SpaceX has abandoned the construction of the prototype Mk 2, and it is still standing there in Florida.

2020: ONE BETTER THAN TWO

Then we saw the two teams come together at the end of 2019 and furiously set about completing the next prototype, Mk1. As we expected, it failed during testing. Ilon tweeted before the test that the prototype would not perform “jumping”. And SpaceX is already working on the next prototype.

This was not the only change. Around the same time, SpaceX also switched from using Mk to SN nomenclature. There were three pressure test specimens that tested welds and the ability of tanks to withstand pressure at cryogenic temperatures. Then there was another full-scale test of the SN-1 tank, which exploded, exploded, and then exploded again when its lid fell. Finally, we have SN-3, which also failed due to incorrect testing procedures. Despite these failures, their next prototype, SN-4, is already ready and has passed pressure tests at cryogenic temperatures.

SpaceX built and exploded three times as many tanks in the past six months as SLS in the past six years! It is here that we see huge differences in the construction, testing and general development philosophy! Time is compressed in seconds.

PHILOSOPHY STARSHIP VS PHILOSOPHY SLS

By now, you probably already have an understanding of the design differences of projects and development philosophy. Just by looking at how these two programs have evolved, the differences become apparent. But there are a few things that confidently confirm how truly different they are.

SLS, LET PLAN EVERYTHING IN ADVANCE

Let's start by putting ourselves in the shoes of NASA. Government-funded NASA must act differently from a private company with private funding. Perhaps the most fundamental thing they cannot do is take risks.

When creating something as large-scale, complex, and ambitious as the SLS project, you really need to consider everything before sending tasks to contractors. If you tell contractors something to build, and then something changes in plan, all their work will be in vain. This inevitably happens when you have dozens of contractors and government employees who all rely on each other to complete their tasks on time.

Imagine if the key part of the project is delayed for a year, what should government officials who develop this system do? You cannot fire them for a year and then return them to the project. They would leave in search of a new job. And you cannot transfer them to something else. It is unlikely that the engine engineer will simply move on to another rocket NASA is working on. Every year there are many costs that are burdensome to implement a program of this magnitude.

NASA, DISTRIBUTE MONEY

Although this is inherently less risky and inefficient, distributing money and contracts to various locations works for political support. There is also a project security system through funding from several contractors and space centers across the country. Such a decentralized approach helps make it more attractive to Congress for budget adoption. Even if it is ineffective, it helps to secure program funding at the political level.

This is especially true when you realize that the Europa Clipper project, designed to explore Europe, the satellite of Jupiter, must legally fly to SLS. Perhaps the craziest fact is that they additionally added $ 250 million worth of storage to the program! The SLS rocket for him will not be ready, at least until 2025. Despite the fact that the probe will be ready by 2023. And this law will help in the long run by supporting the program. In addition, it will be funded for a potentially indefinite period of time during a change of administration.

This situation is clearly far from ideal. But if you are worried about the survival of the program, and not that your goals are shifted 180 degrees every four to eight years, then these things are part of the game.

Remember, NASA’s budget is only about half a percent of our national budget, and spaceflight programs aren’t even half that.

DISCLAIMER, NOT AN OPTION FOR SLS

Consequently, the basic philosophy of building SLS is planning and reducing the risks of implementing the program. There really aren’t many places where you can fail, when you have to answer to the taxpayers why their money literally “evaporated”. Do not forget once again that NASA’s budget is only half a percent of our national budget, and human spaceflight programs are only part of this.

STARSHIP. ANSWER - 42!

Now compare this to Starship. The development of the spacecraft in the literal sense of the word is as fast as possible. SpaceX did not start with detailed drawings. Literally, it started by just finding out what questions to ask. Then, how to formulate the limitations of what their apparatus should do.

Two main goals were born in this process. First, be completely reusable. Secondly, to have sufficient power to be useful for delivering people to other planets. This is really the point. Then you can go back to find answers to these tasks.

The next most important point helps to answer the question of developing an engine that would be effective and could be used repeatedly. As I said in my video about the SpaceX Raptor engine, a methane-fueled closed-cycle engine with complete gasification of components perfectly matches these goals.

Raptor fuel provides soot-free combustion and keeps the engine clean for easy reuse. And its high efficiency improves the use of fuel on board. High engine thrust and small footprint allow you to quickly scale rockets with multiple engines.

From that moment, all the movements of the project were in the sandbox. Do not be surprised when you saw a sudden turn from carbon fiber to stainless steel. You understand how important it is for SpaceX to simply start flying so that they have a starting point for repetition when you hear how Elon explains why it was so important to change the design of Starship.

Starship presentation in fall 2019

STARSHIP ITERATION SPEED

Therefore, the speed of iteration determines why we see so many random things happening in Boca Chica. For this reason, it’s stupid to even worry about future plans. I was mistaken in this, like everyone else, because everything subsequent depends on what will happen now with their current version. Then they will develop the next step after that, based on the results of the previous step, etc.

This is a philosophy similar to the “cascading model” or, possibly, a flexible model standard in software development. This is Ilona's original approach. In fact, you are not working on the second step until you take the first step. Plan for a long period, and you are likely to cancel all work.

This is literally the opposite of SLS, where everything must have an accurate plan. If in the end you build a rocket three meters shorter than the blueprints, suddenly you also have to change the entire ground support system! This incident happened with the SLS and its mobile service tower.

FLEXIBILITY AND SPEED

Everything for Starship is still in limbo at the moment. I mean, we naturally observe how they build a plant around a rocket, and not vice versa. And frankly, this is very risky, but it is also much easier to do. Since the company is extremely vertically integrated, it can move faster and more flexibly. This means that changes in solutions do not have such a strong ripple effect for the project as a more traditional method.

We will see even more equipment failures and prototypes. There will be setbacks. We are likely to see explosions! But, unlike SLS, accidents are a step towards the goal. This approach fosters learning through prototyping at lower cost and greater speed. Ilon repeats again and again: “Failure is a sign of development, if something does not fail, you are not innovative enough.”

This is very similar to the philosophy of developing the Soviet Union during the heyday of Sergei Korolev. Create something as cheap as possible, test it if it explodes, see what went wrong, make improvements, repeat it! And it definitely gave them a head start in the early stages of development. Say you blew up a rocket that you built in two months. We will learn from this. We’ll build another rocket in less time than NASA needs to refuel and experience the SLS once. This is simply a monumental difference in philosophy.

STARSHIP VS SLS

I think the time has come for us to really push these missiles head-on. This will help to understand how truly available they are for comparison when we look at their “bolts and nuts”. After the initial encounter, we look at some of the “rabbit holes” of indicators and opportunities. Get ready!

Parallel comparison of super-heavy missiles by parameters: thrust [MN], load capacity LEO [t], load capacity TLI [t], price [$] and price per kg per TLI.

We have already touched on the size of each rocket, so they are listed here. In the meantime, we just compare the initial assembly of each rocket. Block 1 and Block 1B SLS, as well as a rough version of Starship in its current form.

Be sure to keep in mind that Starship will change a lot in the future. Almost every time a new one is built, it will be different from the previous one. Expect this pace of change to end sometime in the 1920s or even after SN30. SLS can also change a little when Block 1B goes on real flights.

LET'S COMPARE ENGINES

While we're here, let's compare Saturn V and Falcon Heavy! We just have some additional views on how these missiles really compare. SLS is big, but Starship will be huge. It will be larger than Saturn V in overall height, and only slightly narrower than the first two steps of Saturn V, but it hardly narrows like Saturn V.

Now let's talk about engines and their fuel. Falcon Heavy has 27 Merlin engines for sea level operation and one Merlin optimized for vacuum operation at the upper stage. All of them work on RP-1 kerosene and liquid oxygen. There is Saturn V, which had five F1 engines in the first stage, which used kerosene RP-1. Five J2 engines in the second stage and one J-2 in the third stage operated on hydrogen.

As we know, SLS has basically the same design as Space Shuttle. There are two SRB solid fuel boosters and four hydrogen-powered RS-25 engines. In Block 1 configuration, there will be only one RL-10B2 engine in the upper stage, also powered by hydrogen. In contrast, its next version, Block 1B, will have four RL-10 engines, also powered by hydrogen.

Finally, Starship has 37 Raptor engines on the Super Heavy Booster and, most likely, six Raptors on the Starship. This number can be changed, and SpaceX will do this relatively easily due to the small size of the Raptor engine.

LIFTING DRAW

Next, let's look at their draft at launch. As always, this is fun. Falcon Heavy is a child with its 22.8 MN. Then we turn to powerful rockets with Saturn V with its 35.1 MN. The SLS is slightly superior to him at the start with 39.1 MN, but it is Starship who will be the king here with 72 MN in its current configuration.

USEFUL LOAD IN MOON ORBIT

We've already covered some of the payload capabilities of these missiles when deploying to LEO, so let's get back to SLS and Starship. But this time we will show how much mass they can send to the moon. We call this “trans-lunar injection” (TLI), because in any case we are talking about lunar missions. Please note, we will show the load capacity for SLS Block 1 and Block 1B. Nevertheless, their capabilities on LEO are almost the same, since it is the base stage that puts them into orbit.

Note, this is not the mass that the rocket system can bring to the path of flight to the moon. This is the mass that the system can deliver to the moon. You must go into lunar orbit with your spaceship. For Orion or Apollo, the service module will take care of this. Additional energy is required to achieve the characteristic velocity (delta-v) in order to reach a certain point in space.

The Falcon Heavy in reusable mode can deliver about nine tons to the lunar orbit. This also means that all three of the first boosters land on drones, unlike the two boosters landing back on the LZ-1 platform. Compare this mass with 15 tons per TLI in a one-time mode.

SATURN V VS SLS

Next we have Saturn V, which can deliver 48.6 tons to the orbit of the moon. Then SLS Block 1, which can deliver 27 tons. An updated version of Block 1B will raise up to 43 tons in TLI. You may ask how a more powerful rocket can get only half the payload on the moon from the one that could Saturn V? Well, this result is due to the transition cryogenic stage with low thrust for a rocket of this size. Oddly enough, even with SLS Block 1B with its four RL-10 engines on the upper stage, it can deliver only 43 tons to the orbit of the moon. Less than what Saturn V was capable of, to be honest, it baffled me.

Starship is a little confusing for the lunar orbit. Starship alone cannot fly into TLI orbit. Its huge 120-tonne dry mass prevents it from leaving LEO. The flight of all this dead cargo to the moon will not work without its refueling. Refueling is an integral part of the Starship flight plan. But we will talk about this in the next video. This video will discuss whether Starship should use additional boost stages or refueling.

RE-USE OR DISPOSABLE. AT WHAT PRICE?

Now I will show which of these missile systems are disposable, partially reusable and completely reusable. That's where we are going to dive into the deep “rabbit hole”, so take care of your asses. We will talk about the price, and talking about it is not easy. You will understand in a moment why. For comparison, I adjusted all the numbers that you see in US dollars to 2020 prices.

To begin with, what I will call the “rocket price tag”. This is the price you can probably buy a launch for. At the moment, we are ignoring development costs. But we will cover development costs in the next article. For now, just keep them in mind. We will also only look at rockets for now, without spaceships such as Appolo or Orion.

ROCKET PRICE

Let's start with the Falcon Heavy for about $ 90 million. Saturn V was about $ 1.2 billion per launch. After the launch of production of SLS Block 1 and its later version of Block 1B, they will cost $ 875 million. Remains Starship. Well, Ilon claims that they can launch it for $ 2 million. Let's assume that they can someday make for $ 2 million, but for some time it will be wise to take $ 100 million until the market catches up with them. So let's just add $ 100 million there as a price tag for the worst case scenario.

Now with these numbers, we can calculate the basic dollar / kilogram ratio. Since we're talking about the moon, let's see how much it costs to send 1 kg to the lunar orbit for each of these rocket systems.

KILOGRAM / MOON RATIO

Falcon Heavy can deliver a kilogram to the moon for about $ 10,000 in reusable or single-use mode. Saturn V will deliver for approximately $ 25,600 per kg. SLS for Block 1 after the start of production will take about $ 31,500 per kg. For Block 1B, the price tag looks much better, about $ 20,000 per kg. Starship with a single launch for $ 100 million can not reach the lunar orbit. He will need two additional launches to refuel the ship in Earth orbit in order to complete such a flight. It will cost 300 million dollars. Having refueled, it can send a 156-ton payload to the lunar orbit. Thus, the cost of Starship per kilogram will cost about $ 2,000.

These are some very preliminary estimates, and they are based on assumptions. This is for the case if you want to say that we deliberately “interfere” with Starship. Just in case, the launch price is too optimistic. But still Starship is the most economical option possible.

Preliminary calculations are based on arbitrary assumptions. For example, they do not account for development costs. We still have a lot to learn about budgets and costs. In the meantime, just accept this topic. We will explore all of the “rabbit holes” in the next article on spending.

CONCLUSION

How did we get here? How is it that we are simultaneously developing two super-duper-mega-missiles?

I think the story speaks for itself. When NASA started working on SLS, the idea of a rocket like Starship was completely ridiculous. Even today, many people think that this is crazy and an undertaking will fail. Starship is "impossible" - while it is not there. And then, suddenly, literally everything changes in a second.

WILL THE CHIEF BELIEVE?

NASA has been working on SLS and Orion for almost a decade. If SpaceX turned to NASA with Starship in 2011, it would be like trying to sell a four-cylinder 8RX 410 John Deere tractor with a 9-liter GPS-powered turbo diesel engine to a farmer in 1870. However, all the farmer was looking for was to buy a plow for his horse. He simply would not believe you if you mentioned the tractor. Oh dudes, Iowa got out of me again, sorry.

NASA stumbled many times along the way. There were so many programs that they led to a dead end. In developing the program, they suffered from a change in the priorities of the mission, staff, and leadership. They repeated this several times before the program really began to be embodied in iron.

They did what they had to do for the SLS. NASA has chosen a reasonable path, relying on existing technologies, partners and program financing schemes. All this to create a rocket capable of operating in deep space, which is supported by politicians. All this to restore the ability to fly, which they lost almost 50 years ago.

Listen to what I came to, and this is the biggest shock. This is not a Starship! But mankind has a Star Ship. Starship is a logical continuation if it is necessary to reduce the cost of space flights. Honestly, it makes sense to produce reusable missiles. Everyone wants to do it! No one thinks this is a terrible idea. Few engineers or managers think this will ever happen.

50 WAYS TO LOSE A LOVE

I think the biggest surprise is that it took 50 years to build another rocket with the capabilities of Saturn V. After the Apollo 17 mission in 1972, none of the people left LEO. If you told Gene Cernan, the last astronaut who walked the moon, he would not believe it. Hearing this news, he might have put you a “finger” under his eye.

Since then, rocket technology has matured. Now this is not achievable by entire nations, but by a handful of brilliant and courageous corporations. These enterprises can rethink everything related to rockets and space flights. They can open up commercial opportunities and opportunities that previously simply did not exist.

MARS OR WASTE

I know that the purpose of Ilon’s life is to fly to Mars. But on the way to it, he will completely change the access of mankind into space for the better. To get to Mars, you need a reusable rocket with huge capabilities. This crazy proposal will lead to a revolution in the economics of space flight by several orders of magnitude.

The reason we stopped flying to the moon was because it was too expensive. The United States measured its “member” during the Cold War against the Soviet Union using the Apollo project. But this was not a sustainable way of exploring the moon.

Let's think about sustainable ways to explore the moon. This is exactly what we will tell in the next article. By chance, we have already researched and recorded. Get ready and we will answer your question: “Should NASA just cancel the SLS and use Starship and other commercial launch systems?”

Let's see if Artemis will be a step in the right direction or not.

In my opinion, the Orange Rocket is good enough at the moment. But the Shiny Rocket will soon be incredible. We, as a "team space", can note the fact that we live in a time when we will have two super-mega-rockets launching into space at about the same time! YES!!!

Sources:

Harry Liles talks about SLS in 2011
SLS C0 - NASA manifest options
NASA SLS payload user guide
FH TLI payload
calculation 3 landing assault landing calculations
OIG SLS / Orion
report SLS ICPS and EUS newsletter

Source: Everyday Astronaut article
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SLS vs STARSHIP: Why do both programs exist? Everyday astronaut

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