SpaceX, the Heavy Falcon, and the Push for the Colonizaiton of Mars
Founded in 2002 by Elon Musk (the creator of the Paypal online banking system), Space X wants to focus on one primary goal: cheap spaceflight. Specifically, they want to be able to send 1,400 pounds into Earth orbit for about $6.5 million. To put that into perspective, the next cheapest option for such a launch would put you back around $30 million. This is despite the fact that over 30 countries can launch into space and that the U.S. is only responsible for 20% of current launches. Such conditions should offer more competition but sadly do not, and that is where SpaceX is attempting to lead in the private space company race (Lemley 30).
Elon looked at the Falcon 1 (named after the Millennium Falcon) as a basis for a clean slate in rocket technology. He examined the main reasons why spaceflight is so expensive and addressed those in the design of Falcon 1. For starters, he did not rely on old and failing equipment that is difficult and expensive to replace. Often, the space shuttle did just that and it was one of the reasons why it failed when comparing the original cost-projections to the actual. Also, a huge staff means that you have more people to pay for. Elon’s staff totals 130 people and is thus able to keep further costs down (32)
The actual Falcon 1 is a fairly traditional looking rocket. It stands 70 feet tall, has a 5.5 foot diameter, separates into two stages, has an aluminum casing and runs on a kerosene/liquid oxygen fuel source. A typical flight goes as follows: after the ignition of the rocket, Stage 1(known as Merlin) separates to Stage 2 (called Kestral) after 169 seconds and at a height of 297,000 feet. About 5 seconds later and 27,000 feet later, the Stage 2 rockets will fire. 194 seconds after launch, the next separation occurs at 429,000 feet and by 552 seconds after launch the rocket’s fuel supply will be exhausted. The rocket is now at 1,333,200 feet. 18 seconds later, the payload Falcon 1 carries with is deployed, entering an orbit of 317 miles above the Earth. SS1 could only get to 2% of this height (Lemley 28, 30, 32; Belfiore 168).
The Merlin is a simple design: a pintle engine with “high pressure coaxial fuel injection.” It mixes kerosene with liquid oxygen using a turbo pump, sending it to the combustion chamber where it ignites out of one engine with one injector, further driving down costs. This is totally different from the Space Shuttle, which has 100’s of little injectors that ignite. With this capability, Merlin can generate 75,000 pounds of thrust. It also has an added bonus: it can be shutdown at any point in the flight, unlike the Space Shuttle. So long as Falcon 1 proves its worth over and over again, Musk has designs for the Falcon V, which puts 5 Merlins together and can carry 10,000 pounds of cargo into space at about $15.8 million a launch. For the same payload amount, Boeing charges $60 million (Lemley 32-3, Belfiore 176). Falcon V would be almost 75% cheaper!
Another bonus of the Falcon 1 and V is their ability for reuse, something the Shuttle was able to do. About 80% of Falcon 1 can be recovered and reused, while 100% of Falcon V can be recovered and reused for up to 100 flights. Also, these rockets have GPS guidance, are friction welded, and are made of carbon-fiber materials which are lighter and stronger than conventional stock (Lemley 33).
Unfortunately, the Space X program did suffer a setback on March 26, 2006. The Falcon 1’s rockets caught on fire 25 seconds after is launched off Omelek, an island in the Pacific. The system responded to it by shutting down the engines and it fell back to Earth. After reviewing the data, it was determined that a fuel component was not properly secured, which led to a leak. The main computer even detected it and told HQ about it about 6 minutes before the launch but since no automatic kill-switch was programmed for it, nothing happened. Now Space X has a procedure for it and over ten times as many unlikely scenarios, just in case (16).
Falcon 9 and the Future
After that small failure, the team recovered and a few years ago Falcon successfully launched. Eventually though designs changed and the Falcon 9 replaced the Falcon 1 and the proposed Falcon V has been shelved and in its place the Falcon Heavy (essentially three Falcon 9s) has been designed, and will be capable of lifting 54 metric tons. Falcon 9 is 224.4 feet tall, 12 feet in diameter, weighs over 1 million pounds and can successfully put 29,000 lbs into low-Earth orbit and almost 11,000 lbs into geosynchronous-transfer-orbit. The second-stage tanks are the same as the first but shorter, slowing production time and costs to be significantly decreased. Made of an aluminum-lithium alloy, the rocket also has the ability for multiple burns, allowing for multiple orbits to be achieved. ("Falcon 9", "Production at SpaceX").
For this to work, Falcon 9 makes use of nine Merlin engines in the first-stage and one Merlin engine in the second-stage (which will be a vacuum version of the first-stage) to deliver its cargo, which is significantly different from Falcon 1. That cargo is the Dragon capsule, which is capable of deploying solar panels and is designed to deliver cargo (both industrial and human) to the ISS. In 2012, it accomplished this goal, becoming the first private craft to do so. Later in the same year on October 10 another Dragon capsule made it to the ISS. This one, however, was a resupply mission dubbed SpaceX CRS-1. It carried crew supplies as well as additional hardware and was the 1st of 12 planned resupply missions that SpaceX agreed to under the Commercial Resupply Services contract they signed with NASA for $1.6 billion ("Falcon 9", "SpaceX Dragon", "Production at SpaceX").
On September 29, 2013 an upgraded version of the Falcon rocket launched. The Falcon 9 v1.1 launched without any major difficulties and inserted the DANDE, CASSIOPE, POPACS, and CUSat satellites into orbit. This improved rocket had more powerful Merlin engines in the first stage that propel it to 1.5 million pounds of thrust once in space, nearly double that if its predecessor. The configuration of the 9 engines was changed to what is called the "Octaweb," which is not only simpler to manufacture but it also helps ensure the rocket will fire correctly. Additionally, the fuel tank was increased by 60%, the redundancies were increased, and the heat shield was strengthened ("Upgraded", Timmer "SpaceX").
On April 18, 2014 SpaceX CRS-3, the third resupply mission to the ISS, launched successfully and docked with the station a few days later on the 20th. Also, the first stage fired its retrorockets correctly and landed in the water safely, where it was recovered shortly thereafter. The mission brought more supplies to the ISS and also brought some cargo back a month later and was able to show Falcon 9 v1.1 would function normally ("Launch").
The missions SpaceX had done up to this point had a clear emphasis on cargo and satellite insertions. On May 29, 2014, it gave the public the first glance into the human cargo portion of the Dragon capsule program. The new Dragon V2, known as Crew Dragon, is designed to carry 7 people into LEO and is able to land with a combination of retrorockets (dubbed SuperDraco rockets) firing 122,600 pounds of thrust and landing gear, allowing reusability and saving money. It could even be used ten times before needing a replaced heat shield and other maintenance. If operating under ideal conditions, the SuperDraco rockets can accelerate a rocket from 0 to 100 miles an hour in just 1.2 seconds. As for the capsule, it will have two levels to accomidate all 7 people and will be able to escape danger at any point in the flight of Falcon. If everything goes okay, the possible cost per person would be around $20 million, much less than the $71 million that NASA pays Russia to get to the ISS. NASA also shelled out nearly 50% of the production costs to get the Crew Dragon realized (Dillion, "Dragon Version 2," Geuss, Berger "From").
NASA took this and all of SpaceX's accomplishments into consideration when on Sept. 16, 2014 it awarded the company $2.6 billion under the Commercial Crew Program. SpaceX will make use of the Crew Dragon and Falcon 9 to launch astronauts to the ISS as early as 2016, but it will have to pass the same safety measures that the space shuttle went through before launching NASA astronauts. Once accomplished, two to six missions will launch four astronauts a piece. And depending on how those go, more may follow ("NASA Selects," Trimmer "Boeing," Klotz "Award"). Finally, after all the hard years of work that Musk and SpaceX put forth, the rewards have begun.
Now, one of the key features of the Falcon 9 v1.1 is the potential for it to land vertically on an ocean platform. This is a key feature of its reusability, for it reduces the fuel needed by expanding the capability to land anywhere and also puts the platform in charge of meeting up with the rocket. SpaceX got a chance to try it out in mid-January of 2015. Cold-gas thrusters flip the rocket over while grid fins help the rocket stay vertical as it descends and lands on carbon fiber legs. The rocket launched fine, got a Dragon capsule on its way to the ISS, and went down to land. It did find the platform but was not in the full vertical position when it initiated landing due to loss of fluid to the grid fins. Simply put, the rocket did not land. Full disclosure: it blew up. But fortunately it only damaged the floating platform and did not destroy it (Trimmer "SpaceX: Launch," Wall "SpaceX"). Important data will be harvested from this and mistakes will be learned from, as is often the case in space exploration.
As mentioned above, the vertical landing increases reusability (so long as the rocket is intact). Previous rockets could only be partially repurposed (like the space shuttle, whose eternal fuel tank burned up in the atmosphere) at most. Having to produce a new one of these every time you wanted to launch is expensive. However, if the entire rocket survives then cleaning and refurbishment is dramatically reduced as well as anymaterial which would have been lossed, increasing savings. Yes, a bit more extra fuel is needed for the slow-down burns, but the savings justify it ("The Why").
On February 11, 2015 after several delays (one to weather and the other to tech), SpaceX got a big first: a satellite launched into deep space. A Falcon 9 rocket launched the DSCOVR (Deep Space Climate Observatory) satellite, which will eventually reach the L1 Lagrange point after 110 days. The rocket itself was going to attempt a landing on a barge but rough conditions at sea prevented this, so it went for a "soft" landing in the ocean instead (Cooper, Geuss "DSCOVR," "SpaceX Launches").
In an effort to get the Dragon capsule into action, SpaceX had a successful Crew Dragon Pad Abort Test on May 6, 2015. Unlike abort systems of the past, Crew Dragon has the capability to abort at any point on the flight courtesy of the 8 SuperDraco rockets that are designed into the hull of the capsule. These rockets, which burned 3,500 pounds of nitrogen tetroxide and hydrazine for this test, can create a thrust of 120,000 pounds in 1 second, allowing the crew to get thousands of meters away in just a few seconds ("5 Things", Klotz "SpaceX Passenger).
And the good news kept rolling in. Later that same month, SpaceX was given permission by the courts to be contracted by the Air Force to launch military satellites into orbit. This now ends the monopoly that United Launch Alliance (essentially Boeing and Lockheed-Martin) which was a reason for the lawsuit that prevented SpaceX from participating in earlier years. By December of 2014 SpaceX decided to drop the suit against the Alliance which had been in hopes of keeping costs down and competitive. Both are offering different prices and making claims about the competition, so it is fair to say that the game is on (Anthony "SpaceX," Klotz "Game").
A Chance to Learn
That being said, SpaceX had an incident on June 28th of 2015 which hindered efforts for private space companies to visit the ISS. After 18 successful launches, SpaceX had its first failure of a Falcon 9 rocket when it launched its 7th resupply mission to the ISS. 139 seconds into flight, Falcon 9 rocket CRS-7 had a malfunction and 20 seconds later exploded after an over-pressurization in the upper stage caused failure of structure. Amongst the cargo was replacement parts for ISS that were needed after previous resupply missions from other companies failed also. Also lost was an International Docking Adaptors (IDA's), important for multiple private space companies who wish to dock with ISS. NASA was in good spirits though and learned with SpaceX as they progressed forward ("CRS-7 Update", Trimmer "SpaceX Falcon," Thompson "SpaceX Launch," Haynes).
After looking though data collected from 3,000 sources, SpaceX has found the likely source of failure to be a support strut located in the upper stage of the rocket. Its job was to hold a liquid helium tank in place. When the Falcon rocket burns though its kerosene-derived fuel called RP-1, it makes use of liquid oxygen as a main source of molecular action called oxidation. To fill the void in the oxygen tank caused by this is liquid helium, a rather inert element. Because of buoyancy forces experienced by the tank courtesy of a lighter element filling it up, struts need to hold it in place. They are able to withstand up to 10,000 pounds of force but the strut in question failed after only 2,000, disengaging from its connection and dumping its helium without blowing up. One second later and it was over. SpaceX has now switched strut suppliers and will integrate new software to ensure the cargo stage has the capability to deploy parachutes in the event of a failure (Thompson "SpaceX Says," "CRS-7 Investigation," Haynes).
Return to Form
For SpaceX,the third attempt at a rocket landing was the charm, for on December 21, 2015 a Falcon 9 successfully landed back on Earth after orbiting the planet. The only catch was that the landing was not doen on a barge but on terra firma, at Cape Canaveral in Flordia. But it was the first launch since the June incident, it featured some electronic upgrades to the rocket, and helped get the program back on track (Wall "Falcon Returns," Orwig "SpaceX Makes History," Ferron "The Falcon").
With this victory in tow, SpaceX made another barge attempt just a month later. After launching a NASA/NOAA satellite (Jason-3) successfully into orbit from Vandenberg Air Force Base in California, Falcon 9 approached the barge Just Read the Instructions. But sadly, the landing was not successful due to a communications fallout, possibly because of the rough sea conditions at the time. This caused one of the landing legs to break off and thus left the booster no choice but to fall down (Berger "SpaceX," Orwig "SpaceX Just Failed").
On January 14, 2016, NASA released the teams that would receive contracts under the Commercial Resupply Services 2 contract. Amongst the list was SpaceX, who was contracted to send 6 resupply (non-crewed) missions to the ISS from 2019 through 2024 (Gebhardt, Orwig "NASA").
And finally, on April 8, 2016, SpaceX accomplished what it tried so hard to do: a barge landing. This had been after a 2 and a half day mission to drop off an inflatable habitat module for the ISS. And even more amazing is Musk's intent on reusing the rocket for another flight, fulfilling the goal of a reusable rocket for SpaceX. But that is risky, so the engines are fired 10 times in a row to ensure that they are able to withstand the stress again. The next rocket launch proved those stresses are real, for it suffered maximum damage possible as it re-entered our atmosphere at 5220 miles an hour - or about 1 and a half miles a second. It started to break about a half-mile from the surface by igniting 3/9 rockets which slowed the speed of the rocket from 441 miles and hour to 134 in just 3 seconds. It eventually got to the 2.5 miles an hour needed for a successful platform landing, but SpaceX doesn't foresee this rocket being reused (Berger "Like," Klotz "Success!," Ramsey "SpaceX," Klotz "Blazing").
This seemed to get SpaceX into a rhythm, for on July 18 a Falcon rocket landed at Landing Site 1 at Cape Canaveral just 8 minutes after launching. No hickups were detected and the Dragon capsule that was a top the rocket successfully made its way to the ISS to deliver a docking ring for future private spacecraft to use. Mid-August of 2016 would see SpaceX successfully complete its fourth barge landing, hitting a 80% success rate there, and the payload aboard Dragon successfully reached orbit (Klotz "SpaceX Falcon," Berger "SpaceX Is Getting").
And then the helium breach happened. During a September 1, 2016 launch a Falcon 9 carrying a $195 million Amos-6 satellite went up in a spectacular explosion. Seriously, look it up on YouTube. A fault in the rocket's upper-stage oxygen tank caused the material to get so cold it became solid. This created a chain reaction with the liquid helium in a carbon composite container. Reports indicated that the error was not related to the June 2015 explosion. With only 93 milliseconds of data, this was a tough one to unravel with limited data (Klotz "SpaceX: Helium," Berger "SpaceX Still," Klotz "SpaceX Finds").
The Interplanetary Transport System
But Elon Musk did not let that hinder his major announcement at the 67th annual International Astronautical Congress on September 27. There, Elon envisioned the Interplanetary Transport System (ITS), whose initial goal is to get man on Mars. Amazing enough as that is, Elon went further and laid out his vision for planet hopping and colonizing the solar system. Everywhere. But how? First off, carbon-fiber will be the main structural component of most of the rocket including the tanks. This gives a great strength rating while keeping the weight of the rocket down and thus less fuel is required. The rocket would require 42 separate engines that would provide 28.7 million pounds of thrust via a methane based fuel source, picked for its efficiency and low cost. After separating from the space ship, the booster will land on the ground 20 minutes after the launch and then send another craft to meet up with the spaceship. It would contain supplies and fuel for the 100 souls aboard for the long journey. Upon arrival, the craft would use aero braking to slow down and land on pads extending from the tail of the craft, and the Mars colony would begin. Cost projections per person are at $200,000, way less than the current $10 billion projection. With the first practice launch in 3 years, the rocket should land the first humans on Mars in a decade (Milberg).
But...what are concerns and problems that were not addressed at the meeting? For example, space is full of radiation and astronauts would need to be protected. Also, to get a colony started on Mars, Elon plans to use the native resources there but to get to things like water require tons of energy. Interestingly, experts feel the technology and costs are not the biggest hindrance, for the tech is mainly established and the costs are feasible. Also, initial communications will be severely delayed until relay stations can be built and/or deposited in space. And what about laws? How would they work on a brand new world? (Marks)
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© 2015 Leonard Kelley
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