It’s fair to say that there’s really no phase of spaceflight that could be considered easy. But the case could be made that the most difficult part of a spacecraft’s journey is right at the very beginning, within the first few minutes of flight. At this point the vehicle’s booster rocket will be fighting with all its might against its own immense propellant-laden mass, a battle that it’s been engineered to win by the smallest of margins. Assuming the balance was struck properly and the vehicle makes its way off of the launch pad, it will still need to contend with the thick sea-level atmosphere as it accelerates, a building dynamic pressure that culminates with a point known as “Max q” — the moment where the air density imposes the maximum structural load on the rocket before quickly dropping off as the vehicle continues to ascend and the atmosphere thins.
While the vast majority of rocket launches have to contend with the realities of flying through the lower atmosphere, there are some exceptions. By launching a rocket from an aircraft, it can avoid having to power itself up from sea level. This allows the rocket to be smaller and lighter, as it doesn’t require as much propellant nor do its engines need to be as powerful.
The downside of this approach however is that even a relatively small rocket needs a very large aircraft to carry it. For example, Virgin Orbit’s LauncherOne rocket must be carried to launch altitude by a Boeing 747-400 airliner in order to place a 500 kg (1,100 lb) payload into orbit.
But what if there was another way? What if you could get all the benefits of starting your rocket from a higher altitude, without the cost and logistical issues involved in carrying it with a massive airplane? It might sound impossible, but the answer is actually quite simple…all you have to do it throw it hard enough.
It might sound like science fiction, but that’s exactly what startup SpinLaunch is currently working on in the New Mexico desert. The plan is to use their mass accelerator, essentially a vacuum-sealed centrifuge, to spin a small rocket up to a velocity of 8,000 km/h (5,000 mph). The vehicle will experience up to 10,000 Gs before it’s carefully released at the precise moment that will allow it to exit the centrifuge skyward through a rapidly-actuating airlock.
The rocket would then coast to an altitude of approximately 61,000 meters (200,000 feet), at which point it would ignite its first stage engine. From that point on the flight would progress more or less like a traditional rocket launch, with the payload ultimately being accelerated to a nominal orbital velocity of 28,200 km/h (17,500 mph). The big difference would be cost, as SpinLaunch estimates each launch could be cost as little as $500,000 USD.
Currently, SpinLaunch is running tests on a one-third scale centrifuge that has a diameter of 33 m (108 ft) and forgoes the complex high-speed airlock for a simple sheet of thin material that the test projectile smashes its way through when released. This naturally means the centrifuge loses its vacuum upon release, but that’s not really an issue this early in the game; maintaining vacuum will only become important when the system is fully operational, and is intended to help maintain a rapid launch cadence as the massive centrifuge chamber won’t need to be repeatedly pumped down.
So far they have flung passive projectiles to a reported altitude of “tens of thousands of feet”, but that’s a long way from reaching orbit, much less space. The key to making this system work is developing a rocket that can not only withstand the immense g-forces it will undergo while being spun up to speed, but also be able to guide itself during the coast phase before engine ignition using either control surfaces. It should also go without saying that such a rocket only has one chance to get it right — should the engine of a traditional booster rocket fail to light at T-0, the launch can be scrubbed and the vehicle reconfigured to try again. But there’s no do-overs when the vehicle is already flying through the air.
SpinLaunch seems confident they can solve the engineering issues involved, but the fact remains that a similar project was undertaken as a joint venture by the United States and Canada in the 1960s, and things didn’t exactly go to plan.
Technically the High Altitude Research Project (HARP) got its start in the 1950s when ballistic engineer Gerald Bull got it into his head that with a large enough cannon you should be able to shoot a payload directly into space. But anyone familiar with Jules Verne’s From the Earth to the Moon knows that the idea is much older than that. Conceptually it makes a certain degree of sense, and it’s not as if humanity hasn’t spent hundreds of years perfecting gunpowder weapons anyway.
The HARP cannon was built by welding together 16-inch naval gun barrels, and mounted in such a way that it could be raised into a near vertical position. Barbados was selected as the primary test site as its relative proximity to the equator theoretically meant projectiles fired eastward would receive a boost to their velocity due to the Earth’s rotation. Starting in 1962, a series of launches were conducted that saw the cannon fire Canadian-made Martlet sounding rockets of roughly 1,800 mm (70 inches) in length.
Early flights carried research payloads that not only studied the performance of the cannon itself, but also observed upper atmosphere and near-space conditions. Updated versions included solid rocket motors that were designed to ignite after the rocket had coasted for about 15 seconds in an effort to increase their velocity and maximum altitude. The ultimate goal was to develop a multi-stage rocket that could carry a small 23 kg (50 lb) payload to an altitude of approximately 425 km (264 mi).
By the time HARP ended in 1967, the cannon had successfully fired more than 200 Martlet rockets, some of which reached an apogee as high as 180 kilometers (112 miles). With a per-launch cost of just $3,000 USD, or roughly $27,000 in 2022, it remains one of the most cost-effective means of delivering a payload above the 100 km Kármán line that marks the internationally recognized boundary of space.
Unfortunately, despite considerable effort, HARP was never able to develop a Martlet rocket that could successfully accelerate itself beyond the initial velocity at which it was fired from the cannon. Because of this, none of the rockets were able to reach orbit, and fell back down to Earth — often not far from the cannon itself.
The primary issue was the inability to develop a rocket engine that could survive the 12,000+ g’s each rocket was subjected to when fired from the cannon. So while HARP was technically a successful space launch program, it was limited to suborbital research flights which became less scientifically valuable as the more traditional rocket programs spearheaded by NASA began to mature.
Of course, just because the HARP engineers couldn’t design a rocket engine that could survive high g-forces in the 1960s doesn’t mean SpinLaunch can’t do it. It would hardly be the first time a small startup achieved something the entrenched aerospace industry had deemed to be impossible. The company is also clearly aware of the challenge, as they’ve recently released videos explaining that a large portion of their research right now is going towards exploring the effects of the centrifuge environment on various rocket and spacecraft components.
But the fact remains that there are many challenges ahead for SpinLaunch. History tells us that the development of the engine won’t come easy, but there’s truly no precedent for building a mass accelerator of the scale that would be required to hurl their vehicle into the upper atmosphere. One also can’t ignore the reality that the cost of spaceflight is already dropping precipitously thanks to commercial competition between providers such as SpaceX, Rocket Lab, and Astra. A launch price of $500,000 would have been revolutionary 20 years ago, but today isn’t far off from where the market is headed anyway.
That said, all signs point to an exciting new era in space exploration ahead, and it’s not outside the realm of possibility that SpinLaunch could find its greatest success away from Earth. For instance, a SpinLaunch accelerator on the Moon would have a far easier time hurling vehicles into orbit without an atmosphere to contend with. Given NASA’s goal to establish a long-term presence on and around the Moon, a system that could cheaply loft payloads from the lunar surface would likely be in high demand.
One could also imagine a small centrifugal satellite launcher mounted to a future space station to dispense CubeSats and other payloads with limited internal propulsion. It might sound far fetched, but keep in mind that the Japanese JEM Small Satellite Orbital Deployer (J-SSOD) currently in use on the International Space Station uses a simple spring-loaded mechanism to push the spacecraft out of their storage racks. A small mass accelerator that allows the spacecraft operator to select the velocity and even departure angle for their craft would be a clear improvement over the current state-of-the-art.
The fact is, we simply don’t know what the future holds for SpinLaunch. Their current technology demonstrator is impressive for what it is, but at the same time, is so far removed from what would actually be required to achieve their goals that it’s hardly an indicator that the company is on the right track. Only time will tell if they can succeed where others have failed, or if their mass accelerator will join HARP as just another interesting footnote in the long history of spaceflight.
I suspect there aren’t many items that we need in space that also can withstand 10,000 G’s. That’s 140,000 pounds per square inch of pressure, far more than a bug experiences when he goes splat across your windshield. Modern electronics won’t, neither will we or anything contained within a tank or anything with any sort of structure. A block of aluminum would but what are you going to do with that in space?
But the technology could be used as a weapon.
If you actually read the post, it says they have already spun up various pieces of electronics to launch Gs without issue.
I’m sure they were very selective.
Almost any SMD device will survive both enormous acceleration and enormous jerks (change in acceleration) with the exception of some MEMS components. Modern electronics are far more G-tolerant than many assume.
Other than the glass bonded display techs that lots of people have mastered the art of breaking via a small drop – so with pretty low g loads I’d agree.
Sure, SMD assemblies that are manufactured and hardened properly can survive what they were designed for. But you can’t assume that almost any SMD device will survive… Every component is attached with 2 or more solder joints and every one of those solder joints ha it’s point of failure.
For example – We used to test PCB assemblies rated for air flight. Someone made a 1 line error in our shaker table program and the surface mount tantalum caps flew off the board we were testing. And these weren’t large parts, they were only 10 to 35 microfarad caps. The acceleration sheared both solder joints and the glue dots that were holding the caps to the board. I did the math and that one line error change linear acceleration in one direction from 12 G’s to 120 G’s.
In many cases the whole assembly could be potted in a material like epoxy. The potting material surrounds all components and takes the stress, instead of solder joints taking the stress. Of course, that makes the whole assembly heavier….
Yes but what about the stuff you typically find in satellites? Folded solar panels, lightweight main structures, small propulsion systems, antennas, etc… Ruggedizing that to survive 10000g instead of the typical 4-8g will quickly eat away the mass budget.
Less so than you would think, while you certainly won’t be launching the most delicate designs this way with the bulk of the launch energy provided from the ground you can get much much heavier payloads without having to carry more fuel to carry the fuel to carry the fuel to carry that extra weight, which allows for much more durable higher mass payloads to take the G loading.
The HARP program *did* successfully launch electronic instrumentation that survived the 12,000 G’s acceleration. The US Navy also has many “smart” artillery shells that contain electronics. So it *is* possible.
As the photo shows, several rather ordinary electronic items also survived surprising G levels. What do you think the peak G force is when you drop an ordinary integrated circuit on a concrete floor? It’s certainly in the 1000’s of Gs — and yet they survive.
“Many things are impossible only so long as one does not attempt to do them.” — André Gide
‘Is possible’ and ‘is practical’ are far distant cousins.
My mother had a Galaxy S8 phone screen crack, despite a tempered glass screen protector. It fell about 2 feet from the arm of her chair and struck its face on the corner of her laptop that was on the floor. Somehow it managed to strike into the tiny gap between the screen protector and the rubber case. Same thing happend to an S8 my sister had. Fell off her lap onto gravel, onto a chunk that had a point upwards and just the right width to go between the glass screen protector and the case.
Before that, I had an S4 which got knocked out of my hand and of course it fell face down onto a tile floor. Unlike the S8’s mine got the cracked, destroyed the digitizer and the OLED display. Fortunately I had installed Vysor and had it setup with my desktop before that happened, so I was able to copy everything to the SD then wipe the phone.
WWII proximity fuses survived being shot out of AAA and were vacuum tube devices.
Gs and psi of pressure measure completely different things. It’s meaningless to say 10,000 Gs is 140K psi of pressure.
So, what i am wondering: how is this centrifuge balanced, and what happens to the balance once the payload is ejected? Do they launch a counterweight into the earth? Or do they just casually spin up an off balance centrifuge up to 10k g?
More rocket launching, more climate change. Replies Elon Musk and friends, “What, me worry??”
Access to space will absolutely be required if we are to deal with and make real progress fixing climate change, while keeping a human world remotely similar to todays, and things like this and the massive reuseable rockets are making getting those useful satellites and in the near future quite probably rarer mineral imports from space affordable, and vastly more efficient. Way greener than the previous options.
If you don’t have space launching capacity say goodbye to anything like reliable weather forecasting, GPS navigation, and global communications (to name a few) in relatively short order – society relies on it and making it massively less expensive and greener to launch these required services which both SpaceX (as you mentioned Elon) and this concept are taking steps in the right direction for ever better results.
All the things you list can be done well enough with current generation of rockets. We don’t need crazy amounts of launch capabilities. Space mining is unrealistic and not necessary. We can cleanly mine minerals here on Earth for less effort than mining them in space.
The current generation of rockets, at least with SpaceX’s falcon 9 now existing and a few of the more promising looking rivial are not bad – but they only got that way from being relics of the cold war very recently thanks to investment mostly for the commercial uses of space by folks with some vision, with your attitude…
If it wasn’t for them the ‘best’ launch vehicles are very very much obsolete so consuming vastly more, often much more toxic fuels, AND being entirely disposable so vastly more energy wasted in building the launch vehicle… The least green thing you can possible have to provide the services… I can agree we don’t need 8 millions competing LEO internet systems, but that isn’t saving many launches these days..
Space mining really isn’t unrealistic – once you are out of our gravity well you don’t need much energy to shift around so once there give any huge mass the tiniest of push and it will move, and stay moving, very very damn slowly, but more than enough to deliberately crash mineral rich or artificial processed asteroids into a very precise and location many years later.
On Earth really isn’t less effort, you still have to fight with gravity moving the spoil which usually amounts to more than 90% of the material moved, the easy way to get at the mineral you actually want is often strip mining, which is about as destructive a process as you can get, mining often contaminates ground and river water and there is only so much of everything on Earth – once you really start to run out of the rarer or most high demand minerals there is no choice but to get them from elsewhere… And if you want to support anything like the current human population you will need a great deal of rarer minerals for all the electronics… (Note not saying mining on Earth can’t be done cleanly, but it commonly isn’t done even remotely cleanly, and even if it is there is still the hard limit on how much x there is)
Before GPS there was LORAN. Global positioning, at least on land, doesn’t require satellites. Likewise, global communications can be done with cable and land-based microwave, as most of it already is,
That said, loss of space access would be a disaster and improving access to space is a tremendous good.
But with how very much, especially in such an environmentally damaged and global economic world we are reliant on shipping we need coverage over oceans, and coverage that won’t be knocked out by a storm (long term or easily anyway).
And weather predictions are only going to get harder and yet become more relevant – in the last few decades when forecasting got pretty damn good it almost never said anything that important or with improved precision enough to really matter, oh no the picnic got rained on, or the sea is a bit too dangerous to be out on today afterall is about the worse shock you can get as you can see and prep for the by cyclonic storms with or without space, and being such significant forces you prep even when its not expected to pass that close to you.
But now extreme weather is becoming so common knowing if its going to rain any time in the next month, and how badly is going to start becoming important for water consumption and flood protections, and knowing how much sun and wind will be needed to manage the electrical grid effectively.
There really isn’t a way to move forward without space access, though I do agree many things we can and do use space for are functionally replaceable, to a useful enough extent anyway, and its not like if we stop launching stuff now space will suddenly empty, there will be many years of degrading utility from the existing networks.
Everything works in CAD and CGI ..
IDK if the Spinlaunch CEO is the right guy to do it or not, but this dude here comes across as the kind of towering intellect, who in 1895, you’d have to take hours to explain to that IC propelled carriages were possible because you removed the horses, and that his criticism that it was impossible because you’d run the horses over is nonsense.
In other words, I think he sets up a bunch of straw men to knock down, and does a lot of appealing to ignorance, aka “I personally cannot conceive of a way around this huge (minor) problem so of course it’s impossible.”
He is really a smug asshole. Every one of his videos is taking some claims that are made and then comparing against some arbitrary test. Like the one in here where they say they have run tests to mach 6 and so he grabs frames from some arbitrary test in a promotional video and for some reason assumes that is the fastest test they’ve ever run?
I was on a DARPA program that he “busted” to extract water from the air. Spoiler: it definitely works though he insisted it wouldn’t.
so he grew up watching mythbusters and decided that good science wasnt as youtube friendly as what they did.
Mythbusters was far from perfect, but they showed real actual tests and drew conclusions from it – that is 90% of the way to really, really good science, all its lacking is larger sample sizes, a budget sufficient to improve the scale/quality of the simulations and the academic papers and workings to really make replication of their results or refuting of the method more possible.
Just yelling stuff will never work, is stupid etc with no actual proof of anything, making sure to only show what they want you to see is about as far from Mythbusters as its possible to get…
The self filling water bottle?
It might extract water from air (like any bog standard dehumidifier). But the claims it’s promoters make are clearly bullshit and its gofundme backers clearly chumps (who were lucky to get together with their money in the first place).
I wonder if this guy thinks Solar Roadways is a viable technology? Sure seems to be Mr. Opposite.
He hates Solar Roadways. And he does tend to be a contrarian, though he does often have some good points, even if he is a bit of a jerk. In fairness, solar roadways probably is a dumb idea. The angle’s not great, roads get really dirty and making a solar panel tough enough to survive in that environment is really difficult (can’t even make normal pavement roads that last all that long). Better to put panels on roofs and over parking lots first. For that matter, putting panels over the roads (like a roof) might be more practical. I’m sure they’ll keep trying though and maybe they’ll figure something out, but I suspect solar roadways will be a technological dead end – there’s just cheaper, easier, better ways to accomplish the task.
That group in particular are clearly scamming gofundme. They haven’t really started trying yet. Just putting on a show.
However, it remains an immoral and unethical act to let a sucker keep his/her money, so good on the scammers.
Solar bike trails don’t work (been pilot projected, in some mayo on french fries type eurospot). Solar roads for cars are an _idiotic_ idea. They haven’t even worked in a pedestrian quad.
Solar roadways should have been discarded as an idea after an hour of thought. Perhaps set for revisit after they were done with roofs, but no, not even then.
At least that would be a defensible position as removed from the engineering realities that make the idea impractical in tests so far it actually makes some sense on paper – a very large surface area you were building and maintaining anyway that connects major electric consumers and is usually empty (on average in many places) – so lots of good sun capture space.
Story thumbnail is impressive when you consider those are ants in white coats to the lower left.
What I would like answered is how the angular momentum is handled at the instant of launch. The images I have seen show the projectile stuck to the end of the arm. So the projectile is spinning end for end at the same RPM as the arm. That spin needs to be removed at release – how?
Not sure how my comment became a reply – serves me right for expecting the comment section to just work…
As soon as it is released there is no force trying to make it do anything but the drag slowing it down – so its not really spinning end over end at all, as that is only happening because of the external force. All it wants to do is fly dead straight off the arm by its own inertia, and its being tethered to the arm that forces it to go round at all.
If it wants to tumble after release that will be because the COM of the whole thing is wrong or the aerodynamics are and if there is a little residual spin (no system is perfectly going to follow the ideal mathematical models) than the aerodynamics effects should handle it pretty easily, as there is so little of it.
I think the problem there is at the moment of release and for several meters there is no aerodynamics because of the vacuum. It probably sorts itself out a few meters outside, but there needs to be some plan to help it out in the interim. Magnetics maybe.
But even without aerodynamics at that initial stage there shouldn’t be any tumble – as the only reason its circles at all is the constant force of the tether to the arm, release that force and there are no external forces acting on it and its momentum at that point wants to carry it off in a straight line – its not got any stored rotation of its own, you are not giving it any rotation at all relative to itself – as far as its concerned you pushed its nose forward and kept doing it to a great speed and then turned gravity off.
So the only tumbling that should happen is if the release isn’t clean in some way and during the release it gets given a bump that will make it rotate around its COM, or its got a very sloshy payload that when the ‘gravity’ is released could cause similar trouble, and in both cases with the rather stupendous launch velocities involved it will be in the atmosphere and get stabilized by the drag far too fast to actually tumble even if you tried to make it tumble I would think – how far can it possibly start tumbling before being out in the thick low altiude air when being launched at that sort of speed, I think you would have to actively get it spinning around its COM on the arm before launch to even get 1 revolution before even the slightest of stretched sphere level of aerodynamic stability catches it.
Para your comment: I don’t believe in or understand angular momentum.
Why doesn’t the earth stop spinning? There is no force on it, keeping it turning.
“Currently, SpinLaunch is running tests on a one-third scale centrifuge that has a diameter of 33 m (108 ft) and forgoes the complex high-speed airlock for a simple sheet of thin material that the test projectile smashes its way through when released”
The current test system already has the airlock present and in operation: https://mobile.twitter.com/spinlaunch/status/1461534575784443907 The breakable seal is to allow the airlock to be opened in advance of firing and only rapidly close afterwards. The airlock itself is more to prevent a rapid inrush of air whilst the rotor decelerates gradually (rather than rapidly via air friction and subsequent heating) and has no effect on launch cadence, as each shot requires the rotor to be despun to attach a new payload then spun up again, and you may as well perform the attachment in a shirtsleeve environment rather than under a vacuum.
Not sure you would want to use something like this off a spacestation – its one giant gyroscope as you spin it up, which will effect the whole station, and then at release as well – the space station would have to be rather massive (and stiff) with a rather high launch speed needed for the satellite to make using such a system actually better than the simple spring.
Off the Moon however seems like a great idea.
“Off the Moon however seems like a great idea.”
Moon steering sounds like a great idea.
Two launchers spinning in opposite directions, one launching a satellite and another launching something of equal mass at the same time, Newton to the rescue again.
That does mean having to loft more mass to the space station in the first place, which is costly – probably at least – I guess waste containers might be usable.
And its also possible you could use such a thing for dual purpose with clever planning and gain some deliberate course change/boost to reduce the amount of fuel you have to burn.
But it still seems like way to much of a challenge to use such a launcher on anything much smaller than the Deathstar…
“The primary issue was the inability to develop a rocket engine that could survive the 12,000+ g’s each rocket was subjected to when fired from the cannon.”
The primary issue the Martlets encountered was casing design, not the rocket motors. Rocket motors that can survive being fired from a cannon are not uncommon: rocket-boosted artillery projectiles and base-bleed projectiles (rocket-booster projectiles with a thrust below drag) are decades old and in active operation. One nice advantage of purely mechanical launch over chemical launch is that your projectile does not need to fit into and seal against a barrel in a manner that holds pressure. This relieves you of many design and material constraints. The Spinlaucnh projectile for example can be a perfect Sears–Haack body rather than requiring a boat-tail, driving bands, saboting, can be composed of materials not compatible with chemical propellants (e.g. Carbon Fibre), etc.
Is there really *that* much advantage to throwing stuff into space from ground level versus dropping it from a airplane?
A little back-of-the-envelope math shows that at 40,000 feet and 500 knots a rocket bolted to an airplane has about as much speed and potential energy as one thrown from the ground at mach 2.3, without the mechanical overhead of having to be built to withstand 10kilo-G’s, the need to withstand the aerodynamic forces a cannonball feels, or the capital costs of building a 100-yard vacuum centrifuge in the middle of nowhere.
Yes, airplanes cost money, but, they are versatile, and as Virgin and Orbital Sciences have demonstrated, you don’t need anything fancy, you can easily buy an older jet where someone else has taken the depreciation hit. (especially if your parent company is already into aviation and has facilities for servicing large jets)
Unless you’re real goal is having an excuse to build giant catapults in the desert (which is, admittedly, a very cool hobby) I just don’t see where this pencils out.
How much propellant does a launch vehicle consume to reach 20,000 feet and/or 300 mph? Now, have a 747 take your payload that high instead.
Propellant is cheap. With the reusable booster, the falcon 9 basically made plane launch obsolete.
How did you pick your numbers? They said they plan to accelerate to 5000 mph – mach 6.5. Not 2.3 as you have (arbitrarily?) selected.
Not an exact number, just some rough, back of the envelope math. Actually, now that I look at it again, I may have underestimated.
A kilo of mass in a cruising airplane at 40,000 feet has about 125KJ of potential energy and about 32KJ of kinetic energy.
If you threw it up from the ground you’d have to start at about 550m/s (mach 1.6) just to make the height and speed, not counting air resistance.
Assuming a very well streamlined object of about .2m^2 at 550 m/s that’s a couple of Kn of drag at launch (integrate to zero at 12Km). If the launcher weighs 200K, then each K of mass nets about 60Kj to drag.
Of course, that means you need more initial speed because you have to have make 157Kj *after* drag loss is accounted for… so. more speed, more drag… not gonna do differential integration over my morning toast…
so.. guess a number, plug it into the drag equation… close enough… mach 2.3-ish
I meant that you have to invest an amount of energy equivalent to launching at mach 2.3 just to get up to the initial conditions of an aircraft release. Then you have to go from *there* into orbit, so.. lots more, which is why they’re launching at mach 6+
I plan on sleeping with Natalie Portman and Jessica Alba (at the same time).
Putin plans on rebuilding the Russian empire.
Aircraft launch certainly can make sense, but it wont’ be the right solution for all loads – for one thing the aircraft can only ever be the size and power it is – you won’t build a new one to most efficiently carry x (or be able to at all).
Where spin launching can much more efficiently launch much smaller than its maximum potential (at least in theory).
You also have to ask what orbits/flight path your object is supposed to be on – if its a low orbit on a trajectory that is all wrong for the spinlaunch location aircraft is the obvious choice – it can fly to the best launch sites.
That was yet another reason why it pissed me off they broke up the Concordes… just having one for research would have been great.
I thought the Concordes were doing it themselves. B^)
Yeah, but you could stick internal bracing in and weld up all the windows or something if it’s for yeeting things above the atmosphere vs being a mach 2 champagne lounge. There weren’t insurmountable problems for remaining in passenger service really with careful maintenance. The biggest incident wasn’t even Concordes fault but some other hunk of junk dropping crap all over the runway.
Why? There are much more capable aircraft. Sure they are military, so what?
Aren’t the surviving concords all in museums anyhow? Maybe you can pick up a really rough concordski.
Regarding the g-force acting upon the payload. Wouldn’t it be sufficient to increase the acceleration in steps (adding plateaus) to limit the max g experienced by the payload? This should be possible with such a device, unlike when using rockets.
During the spin, there would be constant high g load, even if rpm is constant.
That’s not how centrifugal ‘g’s work. It’s not the acceleration of the increase in spin speed. it is the forces you experience simply by spinning at such a rotation rate.
note – my comment is in reply to the original comment not the other reply that got in before me which I fully agree with
There is the additional disadvantage that the G force in the centrifuge is going to be at a right angle to the main axis of the rocket. Beefing up the rocket structure becomes more complex and heavier than it would be using a linear accelerator.
The problem isn’t the increase in RPM – it’s the spin itself. As long as that thing is spinning at full speed, the object is constantly experiencing maximum acceleration. It’s a giant centrifuge.
I’m not certain but I think the speed at which the centrifuge spins up should be proportional to jolt, not acceleration.
Thanks for the explanation! Physics is definitely not my stronghold, but I’ll try to recall my high-school Physics (or do some research) before I post a naive idea next time ^^
Gotta question just how much math you got though. Real calc is almost always taught in parallel with physics.
Did you take business major calcuseless?
>”but that’s a long way from reaching orbit, much less space.”
Assuming that by “space” it is meant the payload went “above the 100 km Kármán line” the that would be significantly easier than “orbit” and so, their spots should be switched, as the lower bar is mentioned first when saying “much less”.
I’m surprised that spin launch has gotten as far as they have. But, I’m going to say that this is a fancy/flashy way to get investors dollars. I think their end goal is not space but instead something related to development of high powered centerfuges or hypersonic projectiles.
The math just doesn’t work in their favor, since altitude matters very little, if it didn’t, all rockets would launch from planes or high altitude balloon. The fact that their rocket will have to be so much stronger means that it will weight enough to not be worth it.
It really doesn’t have to be all that much stronger, if stronger at all – just differently strong – the rocket has to go through max Q, and survive all the atmospheric forces while being a less than optimal shape, must be strong enough around all the staging points, all very specific places for load. The spinlaunch concept means you can be very much more aerodynamic, and much much smaller as you don’t have to carry all the fuel to carry the fuel to carry the…
The reason all rockets don’t launch from Aircraft is much simpler than you make out – aircraft capable of lifting let alone flying high enough to be worth launching larger payloads/rockets off just don’t exist, and were not very plausible in the 60’s-90’s so didn’t get any development. And a balloon would be such an entanglement risk and have to be stupendously huge to lift the big rockets..
>It really doesn’t have to be all that much stronger, if stronger at all – just differently strong – the rocket has to go through max Q, and survive all the atmospheric forces while being a less than optimal shape, must be strong enough around all the staging points, all very specific places for load.
According to spin launch, their projectile will be launched at 5,000 mph, which is at least 5 times the speed of a rocket at max q, and the spin launch projectile will be at that speed at ground level, where the atmosphere is 3 times as thick. It may be a gross oversimplification, but it will probably be subjected to 15 times the force a normal rocket has at maxQ.
Additionally, they have two choices, fire straight up, and bring enough fuel to reach orbit, which will make their rocket weight at minimum 1 ton (thanks “tyranny of the rocket equation”), probably much more since Hydrogen fuel is out of the question. The other option is to fire at an angle, so that the launch velocity helps it reach orbital speed (and needs less fuel), but, that means lots more time at lower altitudes and a lot more drag.
If you honestly think launching a 1 ton projectile at 5000mph is a good idea, then, good luck.
Another one for the #confidentlyincorrect pile.
https://www.collinsdictionary.com/us/dictionary/english/much-less
I was wondering, isn’t it possible to take an object to great speed on a horizontal rail (with linear induction motor or else) and then have the track point upward at the end?
The shift from horizontal to any point up will increase the amount of g force placed on the object. The more vertical the shift the high the g force.
There was a proposal to build a linear induction motor launcher floated by balloons. In the concept art the launcher rail was in a tube through the middles of a string of large balloons and tethered with some very long cables so it would maintain position. With the top end floating in the upper atmosphere it would provide a high speed jumping off point aimed to the East.
Unlike building a launcher up the side of a mountain, this wouldn’t rely on suitable mountains being so darn inconveniently located. It could also be lowered to the ground for servicing and have its launch altitude and angle adjusted. Might even be able to aim a bit north and south.
I think a linear accelerator up the side of a carefully chosen mountain (perhaps in Hawaii) might be a reasonable alternative. A long accelerator reduces the required G force in inverse proportion to its length, and a launch at 12,000 feet gets you above 35% of the atmosphere.
On the other hand, a launcher in Hawaii would probably have environmentalists throwing fits.
“On the other hand, a launcher in Hawaii would probably have environmentalists throwing fits.”
Just tell them it’s for launching politicians. They’ll be OK with that.
Well this should save NASA some money, get rid of the rockets and just cut a hole in the roof of the centrifuge building! (The astronauts are going to need a pay raise though!)
I say that the true market for SpinLaunch is not finished goods but raw material. Put one of these on the Moon and throw useful materials back to Earth orbit.
Who puts money into these crackpot ideas
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