The asset they have is fat, fat, fat, government contracts. And support for legacy systems they can milk for 10 or 20 years while delivering bupkiss.
Other than that, I completely agree w your analysis.
Let’s not do this, please:
(read the last two lines very closely)
Yes, let that sink in.
This is why proofreading contracts before signing them is critical.
I thought Boeing is in charge of all aerospace “scuttling” these days.
Ok, it’s not just SpaceX that’s getting regulatory pushback due to clean (drinking) water discharges being classified as “untreated industrial wastewater”:
This needs to be streamlined somehow. The water is clean, and this is a place where storms regularly drop thousands of times more water on the area than a few deluge system discharges. I don’t see why they can’t pre-approve a category of water discharges as long as they meet certain cleanliness/volume criteria.
That would be too common sense for a bureaucracy. If it has previously flowed through a pipe and it’s not wanted anymore, it’s “wastewater”.
Posted in an old thread in GQ, reposting here:
A pity. Propulsion technology essentially plateaued around 1965 and didn’t show any signs of advancing again until the last decade or so. One would think a hypersonic air-breathing engine should be doable but apparently the devil is in the details.
Crap. I really had high hopes for them.
One wonders how much this is Wall Street blinkered short-termism and how much this was a crackpot idea that almost could be made to work even given infinite money.
As I said in the other thread, the precooler appears viable and appears to be workable for in-atmosphere craft, but there are other hypersonic jet designs on the drawing board. Their airliner concept the A-2 could go anywhere in the world in 1-4 hours.
SpaceX’s multi billion dollar Starship Human Landing System (HLS) rocket for NASA’s Artemis program to land the first humans on the Moon since the Apollo program will have at least two floors and be capable of carrying a crew of 20 astronauts suggest fresh details on X.
Why do you need to be able to carry this many astronauts at one time?
Could someone clarify as to how many people are expected to be on the Gateway station and on the lunar surface?
Because we want to have an actual legit moon base and not just a flag-and-footprints mission. While the first landing will only have two astronauts (four total, but only two descend to the surface), Starship has enormous internal volume and can handle dozens of people if set up properly.
Not that Artemis isn’t almost certainly a failed program (if they’re relying on SLS to work on time and on budget), but I wonder if SpaceX is using their part of the program to help underwrite the costs of developing Starship.
That’s certainly why they were able to submit a low bid in the first place. NASA considered that a positive for the program–SpaceX having other uses for Starship means they have an incentive to complete the project. HLS isn’t exactly like the Mars lander but a great deal of the tech will transfer over, like the long-term life support systems.
It’s one of those technologies where it’s not clear that the size of the niche is greater than zero. In principle, it occupies some nice middle ground between pure rockets and normal aircraft engines… but in practice it gets squeezed down to nothing.
I think it’s clear that the dream of the SSTO is dead. It never really made much sense. There’s nothing wrong with multistage rockets except for throwing away the discarded pieces, but we now have a solution to that, and it turns out not to even be that hard, because staging occurs at such (relatively) low velocities that you don’t have to go crazy with heatshields or the like.
Every technology, at a super high level, must have a good “impedance match” between the underlying mechanism and the physical application. A LEO rocket needs to achieve a delta-V of about 9 km/s. But our engines only achieve an exit velocity of around 3-4.5 km/s. Therefore we expect 2-3 stages to be optimal, just based on “zeroth order” thinking. And that’s what we see.
Air-breathing engines hoped to make SSTO more practical by improving the effective exit velocity for at least part of their flight, but they just can’t suck in enough air to get the thrust needed to lift a typical rocket. So they have to be used with a spaceplane, which uses aerodynamic lift to reduce the thrust needs. But now you have wings and landing gear and a bunch of other stuff that makes the proposition even worse. Oh, and it basically only works when the propellant is H2, since it has the best cooling capacity and sees the most improvement from not having to carry oxidizer. But the tankage for H2 is enormous.
I just don’t see how it makes sense anywhere. Heavy lift is solved by reusable rockets. Hypersonic passenger jets don’t need rockets. Maybe they’ll benefit from the precooler stuff, but it’s hard to see that. The business case for high-speed passenger transport doesn’t really close in the first place.
The Dragonfly mission is getting real:
Flying on–what else?–a Falcon Heavy.
It’s an octocopter the size of a small car intended to explore Saturn’s moon Titan. Too bad it won’t arrive until 2034. An incredibly ambitious project regardless.
One wonders if there’s an option to speed up the transit by putting it on Starship. Someone needs to develop a massive space tug / kick stage for these interplanetary transfers. Storable liquid fuel, 60 tons or so, maybe itself multi-stage. Should be easy to get 8 km/s of delta V out of it. Spend some of that on an insertion burn at the destination so you can arrive at a higher velocity.
At a minimum, a robust kick stage boostable by Starship would enable a direct Earth-Jupiter Hohmann transfer (I presume a Jupiter flyby is de rigueur for outer system missions) instead of needing to use Earth or Mars flybys. At the destination it’s a question of whether aerobraking or fuel for an insertion burn would be the less massive option.
Improving aerocapture/aerobraking techniques would be great. AFAIK, it’s only been used with Earth, Mars, and Venus.
I can’t tell if Dragonfly will use aerocapture or just a standard gravity assist. I think it would be a first if so!
Using Jupiter or Saturn themselves for aerocapture is a tad more difficult, but probably something we should pursue someday.