|
| Proven wrote:
| [dead]
| cgeier wrote:
| Question for the space nerds: how impressive is this?
| ericd wrote:
| According to the wikipedia article (
| https://en.wikipedia.org/wiki/Prometheus_(rocket_engine) ),
| they're aiming for 3-5 reuses, which I believe is significantly
| fewer than SpaceX's Falcon 9 engine, Merlin. But maybe they'll
| get more in practice.
|
| It's a methalox/methane-oxygen engine, like SpaceX's Raptor, as
| opposed to RP-1 kerosene, like Merlin. One nice aspect of this
| is that methalox doesn't deposit so much soot on the inside of
| the engine, so reuse should be simpler (this is one of the
| reasons for SpaceX's newer Raptor engines also using methalox).
|
| It's got an open gas generator cycle, which means that it's
| likely less efficient than SpaceX's full-flow staged combustion
| Raptors, since it means it loses a few percent of its fuel to
| just running the turbopumps and the exhaust spitting off the
| side, rather than than heading down into the combustion
| chamber.
|
| It sounds like it's much cheaper to build vs. their last
| generation of engine, but we'll see how it ends up in practice.
|
| Getting something like this working is impressive, but who
| knows if it will end up being competitive, SpaceX is still
| iterating really quickly. Not an expert, but the design feels a
| little dated already, in comparison in comparison to Raptor,
| and Raptor is already flying.
| [deleted]
| Diederich wrote:
| > this is one of the reasons for SpaceX's newer Raptor
| engines also using kerosene
|
| Typo there :)
| ericd wrote:
| Oh good catch, thanks!
| frederikvs wrote:
| I'd say it's pretty impressive. Building and igniting a rocket
| engine is hard. For more detail, I can recommend watching "Why
| starting a rocket engine is so hard" by Tim Dodd [0].
|
| It's not "never been done before" impressive, they're a few
| years behind e.g. SpaceX's Raptor engine, which uses the same
| propellants, and is also reusable. But still, a new rocket
| engine is no small feat - the engine is probably the hardest
| part of a rocket. This is quite literally rocket science.
|
| [0] https://www.youtube.com/watch?v=bAUVCn_jw5I
| chroma wrote:
| They're more than a few years behind SpaceX. SpaceX reached a
| similar milestone back in 2016, when they test fired a
| subscale Raptor engine[1] that produced 1 meganewton (~100Tf)
| of thrust.[2]
|
| By 2019, they'd tested their full size Raptor at 1.5
| meganewtons (172Tf) of thrust.[3] The current production
| version of Raptor produces 2 meganewtons (225Tf)[4]. SpaceX
| has successfully tested a newer version of Raptor that
| produced 2.4MN (269Tf) for 45 seconds.[5]
|
| 1. https://twitter.com/elonmusk/status/780275236922994688
|
| 2. "With a thrust of 1MN (225klbf) at sea level, this was to
| be the first methane full flow engine to ever reach a test
| stand." https://www.nasaspaceflight.com/2016/10/its-
| propulsion-evolu...
|
| 3. https://twitter.com/elonmusk/status/1093424663269523456
|
| 4. https://twitter.com/elonmusk/status/1295498964205068289
|
| 5. https://twitter.com/elonmusk/status/1657249739925258240
| breput wrote:
| Positives:
|
| * Uses liquid methane and oxygen for fuel, which is far easier
| to work with than the current Vulcain hydrogen/oxygen fueled
| engine and burns cleaner than kerosene/oxygen engines, which is
| better for reusability.
|
| * This is an engine that might work well on a small to medium
| reusable launcher, which ESA no longer has access to after
| their Vega rocket repeatedly failed and they lost access to
| Russia's Soyuz rockets[0].
|
| * ESA is at least trying to do reusability after dismissing the
| idea for years.
|
| Negatives:
|
| * "100-tonne thrust class" is half the thrust of either
| SpaceX's Raptor or Blue Origin's BE-4 engines, which will be
| similarly reusable and using the same fuels.
|
| * Additive layer manufacturing sounds cool but I'm not sure it
| has any real benefits over conventional engine manufacturing
| techniques. SpaceX is reportedly close to building one Raptor
| engine _per day_ without 3D printing.
|
| * They are undecided on the fuel ("A version using liquid
| hydrogen-liquid oxygen is also being developed."). That is an
| entirely different engine and ground support infrastructure,
| but they are presumably doing it so it could be used directly
| in the Ariane 6 rocket?
|
| * Arianespace/ESA is at least a decade[1] behind SpaceX in
| reusability and due to rocket failures and retirements, and the
| delays with Ariane 6, won't have _any_ flying rockets until
| 2024. So they are far behind and do not have a good track
| record with speedy development.
|
| [0] https://spacenews.com/europe-grappling-with-space-access-
| cha...
|
| [1] https://www.space.com/europe-no-reusable-rocket-until-2030s
| frederikvs wrote:
| The thrust of 100 tonne isn't really that important IMO. The
| Raptor has far less thrust than the F-1 engine used on the
| Apollo missions, but if you strap 33 Raptors to a rocket,
| they can beat five F-1s.
| panick21_ wrote:
| What really matters at the end of the day for actual rocket
| building is thrust per area of nozzle size. Or how much
| thrust can you put under a rocket of some core size X.
|
| Raptor is by far the best engine ever built according to
| that measure.
|
| Prometheus doesn't seem that impressive but we don't have
| all the information on it as far as I can find.
| TaylorAlexander wrote:
| > What really matters at the end of the day for actual
| rocket building is thrust per area of nozzle size.
|
| What? I am a casual observer but I believe specific
| impulse is most important - how much thrust do you get
| per unit of fuel. The amount of fuel you have to carry
| has a huge impact on how much. Of course things like ion
| thrusters have high ISP but not enough thrust for launch
| - but once you get enough thrust to launch a rocket, you
| want a high ISP. High ISP means way less fuel required
| which means even with less thrust you will be okay. So
| thrust per nozzle area isn't strictly that important if
| the engine is so inefficient you need to carry twice as
| much fuel.
| panick21_ wrote:
| If you have a high ISP engine that is low thrust, your
| rocket will either not get of the ground or if it does
| get off the ground it will suffer from a very high amount
| of gravity loses. High ISP on the engine doesn't matter
| when your rocket spends a long time just fighting
| gravity.
|
| High thrust to weight ratio is important for a rocket.
| The higher your TWR the less gravity loses your rocket
| suffers.
|
| There is a reason most rockets main liftoff comes from
| lowers ISP RP-1 engines or solids rocket. High ISP
| hydrogen engines just result in losses.
|
| SpaceX Raptor actually deliberately reduced its ISP to
| increase its thrust.
| marcosdumay wrote:
| There are quite a few important numbers here.
|
| Weight/thrust is important; thrust/area is important; ISP
| is important; thrust/dollar is important...
| lamontcg wrote:
| > thrust/dollar is important.
|
| something more like that is probably the most important
| variable.
|
| all the rest of them impress space nerds, the ones ending
| in per-dollar are the ones that impress accountants and
| finance people.
| dotnet00 wrote:
| ISP isn't everything, even in space, as you don't have
| infinite time to get places, transfer burns etc are more
| efficient when closer to being instantaneous (in terms of
| dV) and capture burns need to happen within a fixed
| timeframe.
|
| Also I think what they meant is that the engine's thrust
| dictates the height above it that it can lift. So lots of
| larger low thrust engines = short and stubby rocket,
| which adds all sorts of limitations (construction,
| transportation, aerodynamics).
| pfdietz wrote:
| High Isp is actually a bad thing in a first stage. That
| stage is done almost immediately, so high Isp doesn't buy
| much, but low propellant density (which tends to go with
| high Isp) makes the stage larger and more expensive. This
| is why launchers tend to use hydrocarbons, not hydrogen,
| as fuel in the first stage. Low propellant density also
| makes the pumps larger and so reduces the thrust/mass
| ratio of the engines.
| ericd wrote:
| That's a good point, I'm guessing the bigger issue is that
| the chamber pressure is 1/3 of the Raptor 2's (100 bar vs
| 300 bar), which I assume means much lower ISP and therefore
| fuel efficiency, and therefore cargo lifting capacity after
| carrying additional necessary fuel.
| mezeek wrote:
| Additive layer manufacturing has major benefits... unless you
| want to have a super-high production rate like Raptor. So
| it's a positive for them.
| hutzlibu wrote:
| Like normal 3D printers, they are slow, but the benefits
| are, that you can change the design quickly and improve it
| - and then in the end you can invest into optimizing
| production with a different manufacturing process.
|
| (But that is of course hard, to get the same results)
| panick21_ wrote:
| Pretty hard to reproduce the exact same design coming out
| of a 3D printer with other methods. Unless you put real
| effort into making sure the part is build-able with other
| methods you could run into real problems.
| ByThyGrace wrote:
| I also wonder about durability of materials. Will the
| engine last shorter or longer due to being additive-layer-
| manufactured, all else being equal? Compared, say, to the
| Raptor?
| panick21_ wrote:
| Today there are lots of different metals that can be 3D
| printed. Some have very high capability. Are there any
| that compete with custom forged parts used in Raptor? I
| don't know, I don't think people outside of industry
| really have this information.
|
| We know that SpaceX has its own material science team
| developing its own alloys specifically for their use
| case. This material doesn't seem to be designed for 3D
| printing (as far as we know).
|
| What if SpaceX had instead invested that money in
| superior material for 3D printing instead?
|
| Maybe somebody who is doing their PhD on material science
| in rocketry can comment.
|
| I would also consider that engine likely has other places
| that would be more likely to put a limiting factor on
| durability so maybe it doesn't matter so much.
| breput wrote:
| I considered putting it as both a positive and negative,
| but I consider it overall a negative until the technology
| is proven to be as strong and reliable as traditional
| manufacturing techniques - not to mention faster and less
| expensive.
| dotnet00 wrote:
| One example of additive layer manufacturing I remember
| reading about when it comes to engines (and I think Raptor
| does use it) is the ability to reduce weight and potential
| failure points by combing parts which would otherwise have to
| be separated with methods of connecting them adding to weight
| and failure points. IIRC the engine cooling solution also
| becomes much easier to engineer and manufacture with 3d
| printing.
|
| When it comes to mass production, 3d printing isn't that
| problematic, as you can just have several printers.
| panick21_ wrote:
| Lots of space companies have different opinions on 3d
| printing. Relativity Space uses it a lot. Firefly doesn't
| as much. 3d printing is just one way of combining parts
| there are others.
|
| > 3d printing isn't that problematic, as you can just have
| several printers.
|
| The faster you want to manufacture the more printers you
| need. Its ok for most engine plant but for SpaceX Raptor
| manufacturing line, it would be challenging.
| causality0 wrote:
| _testing will continue at the end of 2023 at the German aerospace
| agency DLR's test site in Lampoldshausen, Germany._
|
| Uh, so what are they spending the next six months doing?
| AlgorithmicTime wrote:
| [dead]
| martin8412 wrote:
| Preparations for test flight of Ariane 6.
| [deleted]
| [deleted]
| frederikvs wrote:
| ESA really needs to work on how they present this kind of thing.
| Igniting a brand new rocket engine is a sensational event - I
| would have expected at least a video of the full 12 second burn,
| from a good viewpoint. Ideally from multiple camera angles.
|
| But we just get one still image, taken from what looks like the
| worst position.
|
| ESA is doing really cool stuff, but they're doing a bad job of
| convincing people that they're doing cool stuff.
| aeroman wrote:
| The PR part also applies to Earth Observation Satellites (ESA
| and EUMETSAT). (Almost) any time you see a wide area picture of
| the Earth from Space (particularly around a weather event), it
| comes from NASA's MODIS instrument [e.g. 0].
|
| The European (approximate) equivalent, AATSR, had a lot of
| really nice scientific qualities, but it was missing a blue
| channel, meaning that the 'true-colour' images it produced
| always had a blue tint to the clouds. There was a similar
| problem with the European geostationary satellite imager
| (SEVIRI) [1].
|
| Scientifically, SEVIRI was incredibly useful (and far in
| advance of the American equivalent at the time), but the lack
| of a blue channel meant that it was never really used for those
| shots that made it onto the news (and neither was AATSR). When
| you have spent multiple billions on a satellite programme, you
| generally want the public to see it.
|
| I remember being told at one point that this was considered
| such an issue that the Europeans would 'never launch a
| satellite without a blue channel again' - although that might
| be overstating it a little.
|
| [0] - https://www.bbc.co.uk/news/uk-scotland-11901718
|
| [1] - https://www.cloudsandclimate.com/blog/got_the_blues/
| breput wrote:
| They do a similar thing for their launch webcasts - they barely
| show or talk about the rocket and focus mostly on the pan-
| European cooperation aspects. It might be a cultural thing but
| they also know who is paying their bills.
|
| Always. Show. The. Rocket.
| localplume wrote:
| [dead]
| carstenhag wrote:
| On the other hand, I was at CERN once, and they were just
| giving us slides like no tomorrow (and of course also a
| tour). If I was a billionaire (or a politician) I would have
| given them lots of money
| voidfunc wrote:
| I think it's a European cultural thing. They're not good at
| selling sizzle.
| mytailorisrich wrote:
| In Europe we say that Americans know showmanship, which is not
| always meant as a compliment.
|
| This is a cultural difference.
| lamontcg wrote:
| > ESA is doing really cool stuff, but they're doing a bad job
| of convincing people that they're doing cool stuff.
|
| Why does it matter?
|
| They don't need to convince you that they're doing "cool
| stuff", they need to convince the people who want to put up
| satellites that they're going to offer cheap cost-competitive
| launch vehicles.
| MrDresden wrote:
| ESA is a government run entity and as such definitely needs
| the public behind it when it comes to funding.
|
| Not realising that would be gross incompetence on their part.
| booi wrote:
| this is definitely something SpaceX does right. Even the most
| mundane launches is a multi-hour professional production with
| high quality cameras in multiple angles.. even when the thing
| explodes it feels like it went well.
| GuB-42 wrote:
| ESA maybe does too little, but SpaceX does too much, at least
| to my taste.
|
| Looking at SpaceX streams sometimes feel more like a sporting
| event than the coverage of a space mission. I mean, is it
| really necessary to cheer at every successful phase of the
| launch even though these are pretty much nailed down, that
| the mission is still underway, and that the hard part (like
| the landing when it wasn't a routine thing) is up ahead?
|
| For me, NASA is the best. They show the things as they are,
| without trying to pump up the hype. I mean, rocket launches
| are maybe the most awe inspiring thing humanity can do,
| alongside nuclear explosions (imagine nuclear rockets if we
| ever make them). Some of the most iconic footage from NASA is
| technical footage, not originally intended for the public, so
| really, let the thing speak for itself, no need for SpaceX
| cheerleaders.
| palata wrote:
| > this is definitely something SpaceX does right.
|
| To me (european), I don't like how SpaceX shows off. The
| technology is cool though, but when I see their kind of
| communication, to me it sounds like "US marketing".
|
| So yeah... cultural thing maybe.
| reaperducer wrote:
| I don't think of it as showing off. I think of it as
| documenting for posterity.
|
| We're at an inflection point when it comes to space
| exploration. Ar this rate, future generations will have
| days of video and documentation of the accomplishments in
| America, and a footnote along the lines of "Europe did some
| things, too. Visit the sub-basement of a library in an
| office building in Paris for more information."
| palata wrote:
| Not sure who will spend days watching the same rocket
| takeoff and land :-).
|
| Also at this rate, future generations will have to focus
| on _surviving_ with _much_ less fossil fuels (we 're
| passed peak oil), in a world that basically wants to kill
| them due to global warming.
|
| Chances are that days of video of the accomplishments of
| the generation that actively destroyed their world (while
| being fully aware of it) won't be their main concern.
| panick21_ wrote:
| Rockets are one of the things where we simply have to use
| fossil fuels, and its a drop in the bucket.
|
| The resulting services and sats actually help in any
| reasonable climate change strategy.
|
| > Not sure who will spend days watching the same rocket
| takeoff and land :-).
|
| Here is the thing. Anytime can be the first time for
| somebody. If you don't make an effort to show everything
| you do, nobody will ever know you exists.
|
| Yes some space obsessed people will watch everything, and
| that's fine also. But you never get those people if they
| don't see something first time.
|
| I am European too and I like how transparent SpaceX is,
| and they don't even have to be. Arianespace literally
| tried to hide for 1 year that they had major issues with
| Ariane 5. When asked why it wasn't launching they were
| basically saying 'everything is ok'. But eventually
| journalist got wind off the fact that there were major
| issues in the fairings.
|
| The culture of secrecy and non-transparency has done
| nothing but harm to European space flight.
|
| Its not barging to show a video of a test fire or a test
| launch.
| palata wrote:
| > Rockets are one of the things where we simply have to
| use fossil fuels, and its a drop in the bucket.
|
| Well it's more than you may think (don't take only the
| fuel for the flight, but consider the whole construction
| of the thing).
|
| But more importantly, they are making space a business.
| The first plane was a drop in a bucket, but it enabled
| modern aviation. If SpaceX hits their target of 10M per
| flight... rich people will go have lunch in space.
|
| > The resulting services and sats actually help in any
| reasonable climate change strategy.
|
| What? I very strongly disagree. But I won't elaborate
| more than you did.
| panick21_ wrote:
| > Well it's more than you may think
|
| Currently, no its not.
|
| > don't take only the fuel for the flight, but consider
| the whole construction of the thing
|
| Making them reusable is a huge gain in efficiency.
|
| > What? I very strongly disagree. But I won't elaborate
| more than you did.
|
| Earth observation sat measure climate change. We measure
| the atmosphere with sats. We conduct planetary science.
| Sat imagery is vital when looking at ecosystems like the
| Amazon. Space based monitoring is valuable for all kinds
| of application and can increase efficiency of farming,
| mining, infrastructure and so on. Weather satellites are
| vital in many way, including preventing harm people. GPS
| is a vital technology for so many industries. Space based
| communication brings modernity to many people who don't
| live close to major infrastructure.
|
| You simply can't separate modern humanity from space.
|
| Granted space isn't anywhere close to the most important,
| but it does play an important role. Generally energy
| production, heating, transport and steel/cement are the
| real issues. And where the overwhelming focus should be.
|
| > If SpaceX hits their target of 10M per flight... rich
| people will go have lunch in space.
|
| Just like with aviation we need to consider what
| regulation we want to apply to these things. I am not
| against regulating these things.
|
| Your attitude of nobody is allowed to show any pride in
| anything related to fossil fuels and its general bad and
| shouldn't be done is simply no way to go forward.
| neerajsi wrote:
| > Not sure who will spend days watching the same rocket
| takeoff and land :-).
|
| Have you met a small child?
| Aeolun wrote:
| On the balance, I much prefer having the stream to not
| having it. I can always turn the sound/commentary off.
| lo_zamoyski wrote:
| I wonder if they use canned cheering, or get/hire a claque.
| throw_pm23 wrote:
| It is a US/Europe difference in attitude that can be seen
| across all fields.
| adventured wrote:
| Perhaps, however I would expect they would understand the
| immense value of selling it to the European public by
| properly showing them what they're paying for. Getting the
| European public excited about space is half the battle (for
| funding), NASA has understood that for well over half a
| century. Somehow ESA is still oblivious (which helps explain
| their budget).
| goethes_kind wrote:
| They don't need to sell it to the public because the public
| has less than zero say. They need to sell it to the funding
| agencies and that is what they are doing. Also, the
| bombastic American style marketing comes off as insincere
| to most of us.
| Aeolun wrote:
| > Also, the bombastic American style marketing comes off
| as insincere to most of us.
|
| It does. But I also enjoy me rocket videos. Having a nice
| video instead of a still image would not appreciably move
| the meter of my bullshit detector.
| roarcher wrote:
| They're being paid by the public to build something.
| Showing them that it actually works is "bombastic
| American style marketing"? In the US we would call it
| accountability.
|
| Modesty is great and all, but this comes across more like
| "thanks for the taxes, now fuck off".
| xyzzyz wrote:
| You're right in principle, this is indeed how it should
| work in theory. In practice, though, it's all very much
| "thanks for the taxes, now fuck off", and US is not much
| better here.
| JumpCrisscross wrote:
| There is nothing here they could hype without sounding
| bombastic because the only novel bit is it's European.
| Europe produces great marketing when it has something
| worth promoting.
| roarcher wrote:
| Nobody is asking for "hype" or "bombastic marketing".
| Just a video of it in operation. It's a rocket, it's
| cool, people like to see rockets. If you used their money
| to build it, that doesn't seem like too much to ask.
|
| I'm not a European taxpayer so nobody owes me a video.
| I'm just perplexed by the attitude of the (I presume)
| Europeans in this thread. Being proud of the fact that
| your government doesn't care if you're happy with their
| use of your taxes is...I'm not sure what it is, but it
| isn't modesty.
|
| And before anyone (correctly) points this out: Yes, the
| US government doesn't much care what we think either,
| though it does a better job of pretending to. But you'd
| be hard pressed to find an American who will brag about
| it. And at least NASA releases cool videos.
| panick21_ wrote:
| As a European from an ESA member state. Shaking my head
| at how ESA and Arianespace operate is just so frequent
| that I risking whiplash. I can't get bothered by every
| single instance where they do a bad job on minor things
| like this.
|
| I wouldn't even mind if they sucked at things like this
| if they would actually have the right strategy and do the
| large things correct. Sadly they are really bad at the
| large things and the small things.
| JumpCrisscross wrote:
| > _perplexed by the attitude of the (I presume) Europeans
| in this thread_
|
| It's deflection. ESA and ArianeSpace have left a massive
| strategic hole in Europe's capabilities, in large part
| due to the arrogance of their leadership.
|
| I haven't met a capable European (and yes, I think I can
| speak that broadly to this) who couldn't communicate why
| they'd be good at a job or why a job done was done well.
| When people say they're eschewing promotion out of
| humility, it's usually because they don't have anything
| promotable or are bad communicators.
| Aeolun wrote:
| > I haven't met a capable European
|
| Or maybe you've just been unable to appreciate it for the
| ones that didn't promote themselves _your_ way?
|
| I do a really good job, but there's no reason to make a
| big deal out of it because that's what I'm hired for.
| kergonath wrote:
| The public does not vote directly on any of this, and
| science in general is far down the list of priorities and
| thus get very little time in debates and campaigns. None
| of the regular citizens watching this can realistically
| do anything if they don't like it.
|
| The ESA is at its core all about cooperation and has to
| navigate an international landscape very far from the US
| government. It's a technocratic agency; it cannot be used
| for communication purposes by politicians. Their job is
| to do the work and leave the communication bits to
| journalists. On one hand I'd like them to do more
| outreach towards the general population, because history
| has proven time and time again that you cannot trust
| journalists for vulgarisation. On the other, I don't want
| this to turn into a political circus and funding to
| fluctuate as political parties get interested or not.
|
| The good side of this is that science gets done reliably,
| on predictable budgets that span decades and not years,
| even the unsexy science that would not set crowds on
| fire. True, it reduces enthusiasm but you cannot have
| everything.
| panick21_ wrote:
| > Their job is to do the work and leave the communication
| bits to journalists.
|
| Yeah but here is the thing. If you systematically exclude
| journalist. Don't give them any access. Hide everything
| you are doing and not even provide basic video footage of
| a engine test, they don't have anything to work with.
|
| And of course that is even more true when Arianespace is
| flat out hiding damaging information that tax payers
| should know. And ESA supports them in that.
|
| Major issues with Ariane 5 fairings were hidden from the
| public and it took a long time until it came out.
|
| Lets face the facts, ESA has constructed a space monopoly
| and the monopolist is doing everything to hide its
| failures from the public, not giving journalist access so
| they can't talk about it. Journalist that are known to
| ask critical questions are routinely not invited to
| events.
|
| If that is the kind of society you want to live in, be my
| guest. But I prefer that we actually have some
| accountability from our tax pair funded agency and
| monopolist.
|
| > The good side of this is that science gets done
| reliably, on predictable budgets that span decades and
| not years
|
| That's just not really true. ESA has as many project go
| over budget as anybody else. The Ariane 6 is a massive
| delayed and has a massively increased budget (and no end
| in sight). And we could talk about many other projects
| too.
|
| The idea that ESA is some unpolitical agency that just
| executes perfectly is what they want you to believe and
| they downplay all the issues. Journalist that report on
| these issues have to find the details the hard way. But
| because space is so uninteresting in Europe there is not
| much good reporting on it.
|
| Its also not true that ESA is humble and unpolitical. If
| they have something to brag about they do so pretty
| relentlessly. Go read ESA and Arianespace comments about
| SpaceX around 2015-2019, the were basically all over them
| selfes talking about how much superior they were.
|
| And reticently they have done a lot of political lobbying
| to increase their budget and pushing for European space
| flight.
|
| They do all these things, its just less visible to the
| public because the public cares less then in the US.
| Dylan16807 wrote:
| A video (or two) of the rocket surely isn't too
| bombastic?
| noselasd wrote:
| And that's the difference
| masswerk wrote:
| I guess that will happen, when they have a functioning
| system, i.e. a product. (Showing off with some in-between,
| not fit for purpose stage may be deemed somewhat
| embarassing, compare cultural differences.)
| panick21_ wrote:
| Its not cultural. Lots of European aerospace startups act
| not much different then American ones. In some cases they
| are even more over the top then American startups.
|
| This is more about ESA culture then European culture in
| general.
| palata wrote:
| I like to think that ESA tries to do mostly research (even
| though they also like manned missions, which are mostly for
| fun).
|
| SpaceX, on the other hand, is building a very polluting
| business, which IMHO should be forbidden in 2023. But there
| I would think that the people in the EU are more aware of
| the problem than in the US.
| martin8412 wrote:
| ESAs budget for 2023 is a measly EUR7.08B coming from the
| member states which is in return invested proportionally
| into contracts in the member states.
|
| The US spends four times the amount of tax money per
| capita.
| panick21_ wrote:
| This engine development for example, is something that in
| the US startups who don't get much government money are
| doing. And there are like 10+ companies working on
| comparable technology.
|
| Yes ESA budget is small compared to NASA but they also do
| far less things.
|
| And when they do things its not efficient. Ariane 6 for
| example is a minor upgrade over Ariane 5 with mostly
| parts that were developed for Ariane 5 ME. And yet
| somehow it cost will easily pass 5 billion $ and that
| doesn't include even e new engine. And a lot of cost is
| also hidden on other balance sheet, a full accounting
| would be likely more.
|
| That might be about 2x as much as the complete Falcon 9
| (+ Falcon Heavy) + Merlin + Re-usability program cost.
|
| So yes, a comparative small budget, but that doesn't
| actually explain many of the issues.
| aardvarkr wrote:
| How does SpaceX pollute?
| rqtwteye wrote:
| Self promotion is just way more accepted in the US vs most
| European countries. You notice this in ESA vs NASA. I also
| notice it when I read resumes. Resumes from European
| countries are way more subdued than ones from the US.
| fastball wrote:
| ESA isn't avoiding self-promotion, they're just bad at it.
| causality0 wrote:
| I have to agree with you. They're more than happy to
| label anything "NASA/ESA" when the ESA's project
| contribution was fifty Euros and a can of spray paint.
| martin8412 wrote:
| Hey, that spray paint was load bearing!
| panick21_ wrote:
| This is just overplayed. If you look at European rocket
| startups, they don't act much different. Some of them are
| even more prone to hype and exaggeration then American
| equivalence.
|
| Its just that ESA in particular has that culture.
| JBorrow wrote:
| No it's not, this even goes to things like reference
| letters. US letters for the same candidate are always
| much stronger and use very different language.
| teajunky wrote:
| You watch this video about the excitement level of NASA vs
| ESA: https://www.youtube.com/watch?v=mtOGcgWozd4
| lo_zamoyski wrote:
| Even in resumes/CVs. Americans tend to exaggerate and play up
| their experience in a manner you don't see that much of in
| Europe.
| semessier wrote:
| very impressive and competitive - if it were 2010
|
| Note that the Raptor 3 is at 269 tons thrust (vis-a-vis 100 tons)
| and 350 bar chamber pressure (with 100 bar for the Prometheus).
| The raptor is state-of-the-art full-flow staged combustion which
| is described as very tricky, Prometheus dated open-cycle. Raptor
| has been extensively tested and refined for years now and is
| getting very close to real flight heritage. Once Prometheus has
| flight models the Raptor will be at least a decade ahead,
| probably continuing to move rapidly. Taking a guess Raptor is
| probably much cheaper to produce and operate than Prometheus. It
| appears like a failed design by plan similar to a decision to
| continue expendable Arianes provided that 'there are only 10 or
| so launches per year' and implicitly that the system is set up to
| produce throw-away rockets that need lots of resources to produce
| each example.
| dotnet00 wrote:
| As cool as Raptor is, I feel that ESA, as a government
| organization, making any effort towards a truly reusable engine
| is very good when over here in the US, NASA is still forced to
| pour billions into resuscitating the RS-25 while Boeing
| continues to embarass itself with Starliner and ULA rushes full
| speed into using reusable engines in the least effective ways.
| panick21_ wrote:
| NASA doesn't need to invest in its own engines. RS-25 is just
| something congress forced on them. In reality the private
| companies are developing lots of engine, Raptor is just one
| example. I have documented this in my top level post.
|
| NASA and DoD are both committed to buying rockets on
| commercial rockets, and all of the competitors view engine
| development as a majorly important.
|
| There are at least 10 major reusable engines in development
| in the US. And of course Merlin is already flying and
| Prometheus has a very, very long way to go until to reach it.
|
| > while Boeing continues to embarass itself with Starliner
|
| True but that's a fixed price contract. Boeing is spending
| its own money to finish that program.
|
| NASA actually has crewed spaceflight, something Europe never
| even came close to.
|
| > ULA rushes full speed into using reusable engines in the
| least effective ways
|
| Not sure what you mean? ULA is adopting a pretty modern
| engine. That engine took a while to develop but that isn't so
| surprising. And it isn't ULAs fault.
| cubefox wrote:
| After Ariane 5, ESA should probably award fixed price contracts
| to private European rocket startups rather than doing it
| together with Arianespace. But I suspect this wouldn't work
| well with EU funding, since those startups are only located in
| certain member states.
| panick21_ wrote:
| There are a whole host of issues with the idea that ESA could
| do things like NASA does them now. Politics is one issue, but
| there are many others.
|
| > But I suspect this wouldn't work well with EU funding
|
| Just FYI, while EU funds some of ESA. ESA is independent and
| most of its budget is directly from member states.
| Aeolun wrote:
| EU startups would get _huge_ 500k grants! Maybe even up to
| 2M. And the only thing they need to do in return is develop a
| reusable rocket engine.
|
| The reason nothing happens in Europe.
| sottol wrote:
| This is clearly geo-strategic. Also never hurts to have
| competition, see eg Amazon or Google what happens when the
| innovator becomes a monopoly.
| martin8412 wrote:
| The goal of ESA is to have independent space capabilities.
| panick21_ wrote:
| Well actually their STATED GOAL was to be highly
| competitive in the international launch market as well.
| When Ariane 6 was greenlit there was much talk about that
| this investment needed to be made to be competitive and so
| on and so on.
|
| And of course now 10 years later its all like 'all we
| wanted is independent space access'.
|
| Of course if that was the case just flying Ariane 5 would
| have been better. Not having 3 different rockets would have
| been better.
| trompetenaccoun wrote:
| And sadly they're behind even China at this point, which is
| a bit of a joke if we're honest.
|
| ESA is a perfect example for what a bureaucratic monster
| Europe is these days. With a similar budget as CNSA but no
| clear vision and goals, the funds have mostly been wasted
| in recent years. They have the engineers, a good spaceport,
| the knowledge, etc... everything they'd need. But the
| stagnating political culture is holding them back. The US
| went through something similar, but at least with the
| private spaceflight boom the Americans seem to have snapped
| out of it.
| jackmott42 wrote:
| It isn't at all clear yet that their open cycle engine is
| dated. Raptor has yet to prove reliable. Perhaps it will be,
| perhaps it will not. It is fundamentally harder to start the
| full flow staged combustion cycle, so time will tell if they
| can make this work as reliably as they have the merlin.
|
| SpaceX still makes all of their money with a simple open cycle
| rocket engine, and it burns RP1 which is expensive to clean up.
| Prometheus would be better in that regard.
| carabiner wrote:
| This engine is going into their reusable demonstrator Callisto.
| Callisto is a copy* of SpaceX's Grasshopper that flew... _11
| years ago_
|
| * https://satelliteobservation.net/2018/06/02/cnes-director-
| of...
|
| > Callisto is Grasshopper. The Chinese are also building a
| similar prototype, I have no problem saying we didn't invent
| anything.
| 908B64B197 wrote:
| What's crazy is that, unlike this ESA engine and prototype
| rocket, Raptor and Starship R&D is all privately funded by
| SpaceX's profits.
|
| Starship will fly payloads to LEO before this European rocket
| reaches the Karman line.
| martin8412 wrote:
| Considering that SpaceX keeps raising cash from private
| investors, I doubt that very much.
| panick21_ wrote:
| What do you doubt?
|
| Private investors are private funding.
|
| And of course they are raising cash, they have literally
| have the most advanced rocket and satellites projects in
| development at the same time.
|
| I can't find when CALLISTO is supposed to fly, some
| information says its 2022 but yeah I don't think they
| will make that. Starship isn't really in a race with
| CALLISTO so its kind of irrelevant.
| carabiner wrote:
| Yes 2022 launch date would be difficult. Some type of
| gravity field manipulation to create a closed time like
| curve would be required.
| panick21_ wrote:
| Its certainty an interesting engine but for a very advanced space
| program, as they Europeans want to be, it isn't anything ground
| breaking. If some US startup would announce something like this
| everybody would shrug and call it par for the course and not
| particularly innovative.
|
| Europe has never developed first stage close cycle engine. The
| Soviets have mastered close cycle engines as far back as the 60s
| and even today (at least until the Ukraine war) great
| Russian/Ukrainian engine were for sale. And today many even
| startups are working on close cycle engines.
|
| This engine is another open cycle engine while the world for real
| competitive launch vehicles is moving to more advanced engines.
| And those that do not, are not doing it because they want their
| next generation rocket to be there as soon as possible. While a
| European rocket with this engine is at least a decade or more
| out.
|
| It is targeted at being reusable and that is good of course but
| pretty much every modern engine program is gone be restartable
| and reusable. We don't have much information how many times it
| will be reusable, what its startup mechanism and we just
| generally don't have that much information.
|
| So the thing that's kind of stunning here is that Esa/Arianespace
| is developing this one next generation engine and keep hyping it
| and building it up as this next generation engine for Europe. But
| its really nothing special, there are many engines in development
| (some much further along) in the US that are just gone be as
| advanced or more advanced. ESA here looks more like a random
| startup, rather being a leader in technology:
|
| Relativity Space Aeon-R:
|
| https://www.youtube.com/watch?v=W91fO97WAPo
| https://www.relativityspace.com/terran-r
|
| RocketLab Archimedes:
|
| https://en.wikipedia.org/wiki/Archimedes_(rocket_engine)
|
| Or how about Launcher E-2:
|
| https://www.youtube.com/watch?v=Th1mP0bU9L8
| https://launcherspace.squarespace.com/engine-2
|
| Ursa Major:
|
| https://www.ursamajor.com/engines/arroway
|
| SpaceX Raptor 3:
|
| https://youtu.be/h_5ltDjun3g?t=72
|
| BlueOrigin BE-4:
|
| https://www.youtube.com/watch?v=hdS4azOaF2M
|
| There are more that we could mention.
|
| So Europe hear is more like a small fish in a big pond. And
| compared to efforts like Raptor, this is many generations behind.
|
| This is not big ambition from Europe, but doing the bare minimum
| to have something that is somewhat modern. But by the time they
| will get it into a launch vehicle it will look old compare to the
| competition.
|
| The problem is that engine development in Europe is just very
| slow, and integrating engines to rockets is even slower. Consider
| the fancy new Vinci Upper Stage engine. It has been in
| development for over 20 years now, and will likely be 25 year of
| total time from start of development to first flight.
|
| And the worst of it is, the Ariane 6 Upper Stage mass is so heavy
| that Vinci amazing performance is held back by a terrible
| structural design. So even as they have this advanced engine,
| they resulting rocket isn't really great.
|
| ESA has a very, very long way ahead if they want their rocket to
| be more then just launcher military launches from its member
| states.
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