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An impressive and successful landing streak comes to an end.
SpaceX successfully launched a unique Falcon 9 rocket at LC-39A for the in-flight abort test…
A 1970 law could throw a major wrench in SpaceX's plans. //
Ramon Ryan, law student at Vanderbilt University, argues in a yet to be published paper that the Federal Communications Commission’s (FCC) approval for the project might have been unlawful, Scientific American reports.
“There is this law, the National Environmental Policy Act [NEPA], which requires federal agencies to take a hard look at their actions,” Ryan told the Scientific American. “The FCC’s lack of review of these commercial satellite projects violates [NEPA], so in the most basic sense, it would be unlawful.”
NEPA was introduced in 1970 to force all federal agencies to take the environmental toll, covering anything from wildlife preservation to the effects on climate, of projects into account — a requirement that can be skirted with a special “categorical exclusion” if there’s proof a certain project doesn’t impact the environment.
The FCC was granted such an exclusion for almost all of its activities, including in space, in 1986.
Ryan argues that such an exclusion would never hold up in court.
“If the FCC were sued over its noncompliance with NEPA, it would likely lose,” Ryan told the Scientific American, as the agency has never actually been able to prove that commercial satellites don’t impact the environment.
Before dawn on January 10th, SpaceX technicians and engineers intentionally blew up a miniature Starship tank in order to test recently-upgraded manufacturing and assembly methods, likely to be used to build the first Starships bound for flight tests and orbit. SpaceX CEO Elon Musk quickly weighed in on Twitter later the same day, revealing some […]
Becoming a satellite operator has not been without its challenges.
SpaceX performed a hold-down test-firing of the Falcon 9’s first stage Merlin engines Friday. The test-firing is a customary pre-launch checkout before every SpaceX mission, providing a test of launch vehicle systems and a rehearsal for the company’s launch team.
The Falcon 9 was raised vertical at pad 40 without its satellite payload or fairing Friday in preparation for the static fire test. SpaceX loaded super-chilled, densified kerosene and liquid oxygen propellants into the two-stage Falcon 9 rocket, and the countdown proceeded through through the final steps before launch, including retraction of the strongback structure into position for liftoff and pressurization of the rocket’s propellant tanks. //
The nine Merlin 1D engines at the bottom of the Falcon 9’s first stage ignited for several seconds at 1:20 p.m. EST (1820 GMT) Friday, throttling up to full power to generate some 1.7 million pounds of thrust as hold-down restraints keep the rocket firmly on the ground.
SpaceX engineers will perform a data review after the static fire as technicians at Cape Canaveral roll the rocket back to the hangar and prepare to mate it with the JCSAT 18/Kacific 1 communications satellite inside a climate-controller hangar.//
The Falcon 9 rocket slated to launch the JCSAT 18/Kacific 1 spacecraft is a veteran of two previous missions. It first launched in May on a space station cargo mission, then landed on SpaceX’s drone ship in the Atlantic Ocean. On its second flight, the rocket again powered a Dragon supply ship toward the space station, and returned to Cape Canaveral for an onshore landing.
SpaceX is expected to recover the first stage again after Monday’s launch aboard a drone ship in the Atlantic east of Florida’s Space Coast.
The 15,335-pound (6,956-kilogram) JCSAT 18/Kacific 1 spacecraft will launch into an elliptical transfer orbit, then use its on-board liquid-fueled engine to maneuver into a circular geostationary orbit more than 22,000 miles (nearly 36,000 kilometers) over the equator.
Iterative design is faster and arguably better. But you have to be willing to fail. //
This "fail early, fail forward" strategy allows a company to move more quickly and improve its design along the way. It also results in public failures, such as the all-explodey rocket Wednesday. //
For casual observers of spaceflight, this "iterative" design philosophy is very different from the much slower, linear design process used by traditional aerospace partners for large development projects. Under this more traditional process, a company—or, historically, NASA—seeks to avoid the risk of a rocket failing before it is perfected. Years are spent designing and testing every component of a vehicle before it is assembled for a full-scale test. As a result the process is much slower and more costly. //
It is easier for a company like SpaceX working on a self-funded project like Starship to do this than a government agency, noted Phil Metzger, a planetary scientist at the University of Central Florida. "You have to let people see you fail, and you have to push back when the critics use your early failures as an excuse to shut you down," he recently said. "This is why it is hard for national space agencies to adopt it. The geopolitics and domestic politics are brutal." //
MrTeapotSeniorius Lurkiusreplyabout 8 hours agoReader Fav
DanNeely wrote:
It was. OTOH Saturn 1 was highly iterative; with almost every launch prior to the 1b series being a different configuration as they went from a first stage with a mass simulator on top, to a first and second stage with a simulator in place of a payload, to flying a boilerplate Apollo capsule; all while fiddling with the rest of the stack below.
I had the opportunity to hear a bunch of Apollo engineers talk when NASA celebrated 50 years since Explorer 1 was launched. They wanted Saturn V to be iterative to, but to meet schedule, they decided to gamble instead. In general though, all the NASA contractors are highly dependent on simulation and systems integration labs. The perception is that's cheaper than blowing hardware up, but I'm not certain that's true. //
greybeardengineerArs Centurionreplyabout 8 hours agoReader Fav
VidasDuday wrote:
Fail fast. Fail often. Succeed sooner.
Edit: As I recall, the Saturn V stack was also a combined unit and integration test- smoke or blow.
The Saturn V stages were also tested individually. And sometime didn't pass.
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SpaceX launched 60 Starlink satellites into orbit on its most flown Falcon 9 rocket yet, which made a historic fourth launch and landing on Monday (Nov. 11).
This is a video of every SpaceX landing or landing attempt of which a video was taken. I tried to edit it down as much as possible but it still ended up pretty long, mainly due to including Grasshopper and F9R flights (I didn't feel I could use the word "every" if I didn't). I made this because I couldn't find any such compilations on Youtube. Most videos are from SpaceX's Youtube Channel. Thanks for watching and thanks to SpaceX for all the excitement.
Here is the full list of all launches that I used as my notes while putting this together:
SpaceX is making progress assembling its Starship orbital spacecraft prototype, as seen in new photos shared by SpaceX CEO Elon Musk . This full-scale testing version of the Starship will take over for the StarHopper, which was a scaled-down version used to test the Raptor engine initially with low…
Japanese commercial space company iSpace has provided an updated schedule for its first private missions to the Moon, both set to launch on Falcon 9 rockets and land on the Moon as early as 2021 and 2023. iSpace’s goal is to understand and map lunar resources (particularly water ice) and eventually gather and process those […] //
Despite the death of the Lunar XPRIZE, iSpace managed to not only survive but thrive in a more entrepreneurial environment. The company managed to convince several major investors of the potential value of commercial space exploration and became one of a select few spaceflight startups – certainly the only space resources startup – that has raised almost $100 million.
We are pleased to announce 3 new Corporate Partners! Suzuki Motor Corporation, Citizen Watch and Sumitomo Corporation will support and sponsor the HAKUTO-R program with their professional and technological expertise.
We also announced an updated mission schedule for the HAKUTO-R Program. We will perform a lunar landing in 2021 and a lunar landing and rover deployment in 2023.
One could likely climb to the Moon with nothing more than a printed stack of all the studies, analyses, white papers, and hollow promises ever published on the utilization of space-based resources, an ode to the simultaneous promise and pitfalls the idea poses. As many have discovered, developing the ability to acquire, refine, and sell space resources is one of the most long-lead problems in existence. Put another way, funding a space exploration company on the promise of (or income from) space resources is a bit like paying for a solid-gold ladder by selling the fruit you needed it to reach. //
The need to secure funding via investors – investors expecting some sort of return – is the biggest roadblock to space resource utilization. Really, the only conceivable way to sustainably raise funding for space resource acquisition is to already have a functional and sustainable company as a base. SpaceX is a prime example: the company hopes to fund the development of a sustainable city on Mars with income from its launch business and Starlink internet constellation.
Merlin 1D and MVacD both rely on a relatively simple, reliable, cheap, and easy method of chemical ignition, using a duo of pyrophoric materials known as triethylaluminum-triethylborane (TEA-TEB). When mixed, these materials immediately combust, generating an iconic green flash visible during Falcon 9 and Heavy launches, and thus producing the ‘spark’ needed to start Merlin engines.
Generally speaking, TEA-TEB is an excellent method of igniting rockets, even if it is more of a brute-force, inelegant solution than alternatives. It does, however, bring limitations: every single ignition requires a new ‘cartridge’ be expended, fundamentally limiting the number of times Merlin 1D (and Merlin Vacuum) engines can be ignited before and after liftoff.
This doesn’t even consider the fact that TEA-TEB are extremely complex chemical products that would be next to impossible to produce off of Earth, at least for the indefinite future.
To combat these downsides, SpaceX has designed Raptor with an entirely different method of ignition, known as torch ignition. Technically speaking, Raptor’s power, design, and methalox propellant combine to demand more than a relatively common solution, in which spark plugs are used to ignite an engine. Instead, Raptor uses those spark plugs to ignite its ignition sources, what CEO Elon Musk has described as full-up blow torches. Once ignited, those blow torches – likely miniature rocket engines using the same methane and oxygen fuel as Raptor – then ignite the engine’s methane and oxygen preburners before finally igniting those mixed, high-pressure gases in the combustion chamber. //
the fact that Raptor is a full-flow staged-combustion (FFSC) engine means that the pressures it must operate under are extreme, verging on unprecedented in large-scale rocketry. Extremely high-pressure gases (on the order of 3,000-10,000+ psi or 200-700+ bar) are just as difficult to reliably ignite, especially if hypergolic solutions (i.e. TEA-TEB) are off the table.
Like, seriously. //
On Thursday morning, United Launch Alliance's Delta IV Medium rocket took flight for the final time. //
Since 2002, this rocket (which can fly with or without small, side-mounted solid rocket boosters) has flown 29 missions. All have been successful. //
But the venerable Delta rocket will fly no more. Put simply, in today's marketplace—in which United Launch Alliance must compete with SpaceX for national security launches and with many other providers for commercial missions—the Delta-IV Medium cannot compete.
A 2017 report by the US Government Accountability Office put the per-unit cost of a single-core Delta launch at $164 million. This is nearly three times the price of SpaceX's Falcon 9 rocket, which can not only be re-used but has comparable or better performance. //
To compete more effectively in this new landscape, United Launch Alliance is phasing out its use of heritage Delta and Atlas rockets in favor of a new Vulcan-Centaur rocket. In dropping the Delta IV Medium, the company is eschewing Aerojet Rocketdyne's costly RS-68A main engine in favor of the less-expensive BE-4 engine under development by the new space company Blue Origin. Similarly, it is seeking to cut costs on Vulcan in other ways, while maintaining its performance.
The immediate thought that would probably come into your mind would be "Because 4 legs is more stable than 3." However that is not always true. 3 legs offer the same or in some cases more stability...
According to comments made to a member of the space industry by a RUAG spokesperson, the prominent aerospace supplier may have finally reached an agreement with SpaceX to manufacture a handful of larger payload fairings for future Falcon 9 and Heavy launches. In the likely event that SpaceX is one of two contractors awarded a […] //
European company RUAG has effectively cornered the Western rocket fairing market, with SpaceX being the only Western launch company currently building its own fairings. RUAG builds fairings for both Arianespace’s Ariane 5 and Vega rockets and ULA’s Atlas V. Additionally, RUAG will build and supply fairings for both companies’ next-gen rockets – Arianespace’s Ariane 6 and ULA’s Vulcan – and builds fairings for a number of smallsat launch companies.
Ben Blackburn says:
August 5, 2019 at 3:34 pm
Airlines land, refuel and take off all the time, and all the pilots do is walk around and kick the tires between flights. That is the goal for Starship.
Yes, they will inspect any heat shielding that it has after every flight, but it will be designed so that it doesn’t take months to inspect like the Shuttle,, and won’t need repair under normal circumstances.
The shuttle used an aluminum skin and structure, so any heat leakage would cause catastrophic failure because the aluminum just falls apart..Starship will be stainless steel, so it may warp or melt in worst case scenario, but only where the damage is, and they won’t have crew or fuel directly on the other side. So much more robust design, and being a simple shape, much less complicated heat shielding design.
The Starship booster is about the same diameter as the Shuttle external tank, and about 50 feet longer.
It will have more fuel, and more power, than the shuttle did.
And then Starship will be sitting on top of it, instead of on the side like the shuttle.
And unlike the shuttle, Starship has a lot of fuel on board itself.
The shuttle only used fuel from the external tank and had none on board.
So when you look at the total fuel on board the full stack its considerably more than shuttle had.
This is possible because the Raptor engines are more powerful and efficient with the ffsc design.
As far as fuel for landing, it will take very little fuel for the booster to land, because most of its weight will be gone as fuel is burned on ascent so it just needs enough to run 1 or 3 out of the 31 engines and only for a few seconds.
Ben Blackburn says:
August 5, 2019 at 3:12 pm
The check valves were needed to prevent propellant from going from the propellant tanks back into the unpressurized helium lines.
There is a valve at the helium tank, long pipes taking a twisted path to the propellant tanks, a check valve at the propellant tanks, and then throttle valves between the propellant tanks and the engines.
Once the helium valve is turned on, the pressurization lines are at a higher pressure than the propellant, so no propellant will get back up into the helium lines.
And once the system is activated and pressurized, it will stay pressurized until it lands and is safed, either for abort or for propulsive landing.
The throttle valve is what controls the engines for maneuvering, the fuel system stays pressurized.
In order for propellant to mix, it would have to travel upstream a long distance through 2 long and twisty pipes, and then back feed through 2 pressure regulator valves, and finally to the manifold at the helium tank.
That’s not going to happen!
What did happen is that a small amount flowed back through a check valve and pooled in a low spot in the piping, and then when the system was pressurized rapidly, it was driven at extreme force down the pipe, like water hammer burst the check valve, and under the high pressure and temperature of the impact reacted with the titanium in the valve causing the explosion. It wasn’t propellants mixing that caused it, and as long as the system is pressurized, the helium prevents the back flow.
SpaceX is irrevocably on a path to a much larger craft called “BFR” or the more family-friendly “Starship”. This is intended to have all of the features that Falcon and Dragon are not getting. They developed a staged-combustion full-flow engine to fly it. This is more powerful than other engines, and around twice as complicated, as there is a fuel-rich and an oxidizer-rich pre-combustion stage, each with its own turbopump. This recently flew on the hopper prototype in Boca Chica, Texas. However, it avoids pumping fuel and oxidizer on the same shaft, as all conventional liquid-fueled rockets do today, which requires a lot of the seal between them.
This was the first flight of that sort of engine not to end in explosion since 1969, when the Russian N1, their answer to the Saturn V, failed 23 seconds after lift-off, causing one of the largest non-nuclear explosions in history.
Despite this entire project looking far-fetched and being carried out in an unconventional way (construction of major components outdoors, a low-fidelity prototype that could have been a water tower, but flew), they have made tremendous progress. SpaceX and Musk make very ambitious bets, and carry them out, which appears to have been missing from other space efforts.
I understated. It was the first flight of that engine type ever which did not end in explosion. I think only three design attempts have even made it to a test stand.
When the SpaceX Dragon spacecraft reached orbit for the first time in 2010, it was a historic achievement. But to qualify for NASA’s Commercial Orbital Transportation Services (COTS) program,… //
Unfortunately, this complex dual-function system has now become something of a liability. SpaceX believes the explosion in April was not due to a fault in the SuperDraco engines themselves, but in a leaky one-way check valve. Put simply, the propellants leaked into a part of the system in which they were never designed to be. When the propellant tanks were pressurized in preparation of firing the engines, the foreign liquids caused the plumbing to rupture. The resulting release of the highly energetic hypergolic hydrazine and nitrogen tetroxide propellants used in the SuperDraco tore the spacecraft to pieces almost instantaneously. //
Replacing the valves with single-use burst discs means the SuperDraco engines cannot be fired until they are actually needed, and when they are activated, they’ll likely be run until the propellant tanks are dry. In short, the switch to burst discs means the SuperDraco engines are much closer to the traditional “one and done” abort systems than SpaceX originally envisioned.
"Boeing became furious and tried to get me fired." //
In the early and mid-2010s, Sowers was leading the advanced programs group at United Launch Alliance (ULA), the rocket company co-owned by Boeing and Lockheed Martin. Propellant depots were among the technologies he was working on. Sowers is now a professor at the Colorado School of Mines. //
One of ULA's chief assets was its Centaur upper stage, and the company wanted to build an innovative version that could be refueled in space, and reused, called the Advanced Cryogenic Evolved Stage, or ACES. As part of this development, in 2011, ULA proposed an in-space test of depots to NASA that would cost less than $100 million.
"We had released a series of papers showing how a depot/refueling architecture would enable a human exploration program using existing (at the time) commercial rockets," Sowers tweeted on Wednesday. "Boeing became furious and tried to get me fired. Kudos to my CEO for protecting me. But we were banned from even saying the 'd' word out loud. Sad part is that ULA did a lot of pathfinding work in that area and could have owned the refueling/depot market, enriching Boeing (and Lockheed) in the process. But it was shut down because it threatened SLS." //
SpaceX privately developed the Falcon Heavy rocket for about $500 million, and it flew its first flight in February 2018. It has now flown three successful missions. NASA has spent about $14 billion on the SLS rocket and related development costs since 2011. That rocket is not expected to fly before at least mid or late 2021.