Rocket Lab announced a bunch more details about their upcoming Neutron rocket:
It’s a pretty nice-looking design. It’s still only first-stage reusable, but their second stage is very minimal. It’s a different approach than SpaceX, depending more on lightweight materials than high performance engines. It’s methane+oxygen, like Starship.
They must be using a lofted trajectory to get away with fairing deployment at the same time as second stage ignition. Normally the fairings are deployed some time after when the atmosphere is a bit thinner. But here, the fairings stay with the first stage, which implies that their trajectory goes up a bit more than usual. That would also help with the return-to-launch-site landing.
It won’t be competitive with Starship in the long run, but it should be competitive with Falcon 9, and it’ll probably be a while before Starship really works as intended. So it may well be competitive for a reasonable time (giving Rocket Lab some runway to develop second-stage reusability).
I love it. It’s great to see so many organizations working on different architectures to achieve cheap spaceflight.
I wasn’t thrilled with his materials demo. No one doubts that carbon fiber will resist deformation better than an equivalent thickness of steel or aluminum. But that’s not really the critical parameter, and there are a lot of problems with carbon fiber. For example, loss of strength when it gets hot. Also, composites always promise weight reductions on paper, but it never seems to materialize in production. The Beech Starship was supposed to be light because of composite constructiin, but that never worked out.
Carbon Fiber is a perfectly viable material for rockets, and may be the best choice in this rocket. But his impact test doesn’t demonstrate that. Not one little bit.
Yeah, I like this one because it comes from a credible company but is also notably different from the SpaceX approach. I enjoy the far-out stuff like SpinLaunch, but Neutron is at least 10x more likely to happen (probably more like 100x). And not just another F9 clone like some of the Chinese or European outfits.
I agree with your critique about the materials demo. The results would also have been very different if he used a pressurized tank.
That Neutron rocket looks really cool and I love some of their design solutions. SpaceX go with stainless steel for Starship because it is easy to work with and actually gets stronger when it is cold. It’ll be interesting to see how useable their carbon composite material really is. You can’t just bolt or weld stuff to it as you go along.
One big difference is the lack of upper-stage reusability. The thermal environment is way worse on the upper stage, even with thermal protection tiles. The Rocket Lab solution is to enclose the whole upper stage and make it really cheap; barely more than an engine and tank.
I also wonder if the carbon fiber gives them enough structural margin to not need pressurization. You need some pressurization at first to feed the engines, but once it gets going the acceleration forces may be enough. As such, they may not need all the pressurization hardware (either helium or autogenous) that others need.
I do wonder if SpaceX will use CF for the booster once they really dial things in. It’s too expensive, given the size of Starship, to iterate with it right now. But maybe in the future. Neutron is small enough that they can iterate relatively cheaply. And maybe SpaceX will benefit from whatever lessons are learned from Neutron (Electron uses CF too, but at a much smaller scale).
My video link above stopped working, but here’s an updated one:
Peter Beck answered a few questions over Twitter:
I didn’t catch the part about the suspended second stage the first time around; that’s an interesting design decision. They claim that they’ll have the lightest second stage ever, which I presume means mass fraction. SpaceX is at about 28 to 1 (3.5% dry mass), which is insanely good, but maybe they can exceed that with their reduced constraints.
Yeah, it makes sense. The stage is no doubt much stronger in tension than compression, so hanging it should result in less material required on the stage itself. Clever.
In the meantime, SpaceX has a real issue with Raptor production - Musk says it’s a big enough problem to bankrupt tye company if they don’t fix it. He fired the guy in charge of Raptor production, who apparently didn’t bother to send information about the problems upstairs.
Musk also revealed that SoaceX needs to fly Starship at least once every 2 weeks in 2022, or their finances are in trouble. That sounds like a really tall order. Any technical problem or regulatory hurdle or production problem could throw their entire launch schedule into the garbage. I reslly hope thry aren’t on that tight of a shoestring. Maybe Elon’s selling of 10 billion of Tesla stock is related. He might need the capital for SpaceX.
I’m rooting for the others becuse no matter how nice your SoaceX basket is, you shouldn’t keep all your eggs in it. Rockets are hard.
Their Raptor issue won’t sink the company on its own. But Musk has experience with capital liquidity drying up at just the wrong moment, and is understandably concerned that SpaceX could see the same fate. Starship and Starlink are both expensive.
I’d thought that Musk’s stock sale was more related to taxes and expiring options than needing cash, but you could be right. Might be worth stashing a few bucks for a rainy day while Tesla is riding high.
I didn’t check for any additional people being launched before Blue Origin launch tomorrow. There’s now three more people on ISS, including that Japanese billionaire. So now the new record, for one minute and not all in orbit, will be 19.
The James Webb Space Telescope launch is now December 24, 07:20 (Eastern Time). Christmas Eve. They had a glitch in the ground-to-vehicle telemetry that added a couple of days delay, but the problem was in the cable connected to the vehicle, so no issues with the launch vehicle or the payload.
You can watch the launch live on a number of sites. here’s one.
The launch will either signal the start of a new era in astronomy or be the most expensive fireworks display in history.
As I understand it, most of those failure points are not during the launch, but rather over the subsequent several months when the sun screen and mirror segments have to unfold exactly right. They probably should have included a small robot that can move around and unstick anything that’s not releasing right.
There are a few space missions that might have been saved with just a little percussive maintenance.
It would be pretty funny, actually. It’s too far out for human repairs. But if some deployment failed due to cold welding or bearing failure or something–sending a little robot that could just bang into the affected unit might well do the trick.
That page is contradicting the graphic it’s displaying, since that graphic shows things deploying as it’s moving out. As far as the “several months”, it’ll take about 6 months (if everything goes right) to commission it, and I probably got the two conflated.
One of my cubesats failed (probably) because the solar panels were held in place with Spectra oriented-strand ultra-high-molecular-weight polyethylene synthetic fiber (ok, fishing line) and the cutter didn’t work. A little robot with a tiny pair of scissors would have saved it…
A cubesat to way too small and cheap to invest in a robot, but the Webb Telescope is costing multiple billions. And has way too many ways it can fail. A robot with a camera or two, and one or two general purpose arms/hands would be good insurance.
