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Blue Origin's New Glenn blows up during static fire test

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Re: Blue Origin's New Glenn blows up during static fire test

#271

Post by SyzygyRhythm »

userbinator wrote: post #113

Does anyone else find it surprising that rockets are a century old[1] and yet still seem to fail spectacularly with amazing regularity, often due to some small flaw? Is it just that they're still relatively niche machines and thus haven't benefited from mass manufacturing improvements? [1] https://en.wikipedia.org/wiki/File:Goddard_and_Rocket.jpg

There are a number of ways of looking at this, which others have answered, but here's another:

The kinetic and potential energy of a 1 kg mass in orbit is around 33 MJ. The chemical energy of 1 kg of methane+oxygen propellant is only about 11 MJ.

Alternately, perfectly combusted methane-oxygen propellant has an exit velocity of around 3500 m/s. But you need about 7800 m/s to get into orbit.

Chemical energy is just very weak compared to the energy of things in orbit. It's really shocking that we can do it at all.

The result of this is that your vehicle is going to be almost entirely propellant. You simply can't just build a big, beefy rocket that's, say, only half propellant, with lots of extra safety margin for things that go wrong. Cars and bridges and things have immense margins. Airplanes, a bit less so, but still more than rockets. Rockets live right on the edge of what's possible, and as long as we use chemical thrust it'll always be that way.

Which isn't to say that rockets won't get more reliable. The Falcon 9 has had hundreds of flights since the last failure, and it isn't as optimized as it could be. But there will be a lot more failures before we get there.

Re: Blue Origin's New Glenn blows up during static fire test

#272

Post by generuso »

catlikesshrimp wrote: post #186
generuso wrote: post #116

Earlier quoted context omitted.

You are talking about the energy of the blast. In my comment I was talking about the heat output. From the followup comments it seems I have not made it sufficiently clear. The energy of the detonation wave in rocket explosions is typically 1-2% of the energy in the fuel, at least that is the ballpark of what people use for estimating the effects of mishaps. We also do not know if the tanks were fully filled -- it th…

About the couple of times you have said "fully filled", is that a specific industry or engineering slang or term?

Maybe it was a bit too colloquial. I am not sure if this is very important. A formal term would have been "full propellant load." The phrase "fill level" is also used in NASA documents.

The question was whether during this test the stage was loaded with the same amount of fuel as for an actual flight, or only a small fraction of that.

Re: Blue Origin's New Glenn blows up during static fire test

#273

Post by Laremere »

oconnor663 wrote: post #130
userbinator wrote: post #113

Does anyone else find it surprising that rockets are a century old[1] and yet still seem to fail spectacularly with amazing regularity, often due to some small flaw? Is it just that they're still relatively niche machines and thus haven't benefited from mass manufacturing improvements? [1] https://en.wikipedia.org/wiki/File:Goddard_and_Rocket.jpg

https://web.archive.org/web/20120503175355/https://www.nasa.... > The percent propellant has huge implications on the ease of fabrication and robustness in achieving the engineering design (and cost). If a vehicle is less than 10% propellant, it is typically made from billets of steel. Changes to its structure are readily done without engineering analysis; you simple weld on another hunk of steel to reinforce the fra…

To add to this excellent explanation: Rockets have a fundamental problem. They need to go absurdly fast. If you have a rocket that can reach speed X, to go faster than X you need to reach X but also have fuel left over. However to get that fuel to speed X, you need even more fuel. This is the tyranny of the rocket equation.

Roughly put, the rocket equation is: change in speed = (engine efficiency) * log(mass of the rocket with fuel / mass of the rocket without fuel). So there's limited parameters to play with:

- The speed you need to reach is fixed.

- You can change the weight of the payload. Payload (eg, satellite) designers try to make things as light as possible, rocket designers try to give as much capacity as possible, and everyone prays they can meet in the middle.

- You want as little propellant as possible for cost and practicality, but mostly the other parameters fix how much you need. If the other parameters aren't good enough, you can easily get results like needing a rocket the size of Central Park. [1]

- You can make the engine more efficient. This means running it hotter with higher pressure, pushing the limits of material science. [2]

- You can make the non-payload static parts of the rocket lighter. This means removing structural integrity. It also means making the lightest parts to complete hard tasks like being a valve for cryogenically cooled, literally the smallest element, hydrogen.

Both the engine and non-payload static mass are essentially asking the question "How far can I push this without it breaking". Get your answer to that question even slightly wrong on any of the thousands parts in a rocket, and suddenly all of the fuel that you're using to go in one direction fast decide that you should instead go in every direction fast.

[1] https://what-if.xkcd.com/24/

[2] Or not using chemical propulsion. However things like ion engines don't have enough thrust to get through the atmosphere and into orbit, and things like nuclear propulsion spew fallout everywhere.

Re: Blue Origin's New Glenn blows up during static fire test

#274

Post by bruckie »

kolinko wrote: post #212
kitd wrote: post #195

Earlier quoted context omitted.

Interesting post. I'd never thought of it that way. Not consciously anyway. Might that make an air-launched system more reliable? Even if it's less efficient, the TCO would be lower using a winged system for the initial phases of launch.

It wouldn’t help much, sadly. Getting to orbit is about speed, not height — you need 27000 kph to get to orbit, and having an air launched platform would shave off 1k kph off it at most, perhaps 5k with some insane hypersonic engineering.

It helps a bit more than you imply, though: if you can launch from a higher altitude, you have less atmosphere to plow through. That lets you use more of your propellant to speed up instead of to push air out of the way.

Re: Blue Origin's New Glenn blows up during static fire test

#275

Post by xboxnolifes »

userbinator wrote: post #164
areoform wrote: post #138

Earlier quoted context omitted.

I've talked about this a few times before but – https://news.ycombinator.com/item?id=47726133 / https://news.ycombinator.com/item?id=47726078 - to repeat myself; It's because we're a very primitive species, and the forces involved here are genuinely new. It's physically not possible at our current level of technology to make this "safer" due to the distances and energies involved. I will let John Young explain it his…

and the forces involved here are genuinely new I remember growing up with things proudly advertised as "space-age technology"... which largely meant the 1950s and 1960s, and of course it's what got us to the moon, multiple times. Yet more than a half a century later, new rockets just don't seem that impressive in comparison.

Personally, I'm impressed with just how unimpressed I am. Or rather, rocket launches feel like they really are becoming more and more commoditized. To the point that routine trips to the moon doesn't feel like a crazy future.

Re: Blue Origin's New Glenn blows up during static fire test

#276

Post by imtringued »

JumpCrisscross wrote: post #40
dgrin91 wrote: post #30

I would guess this puts a big dent in NASA's moon plans. I think Blue origin was _just_ selected to be the first moon lander mission. Now they are going to be grounded _again_. They just got off grounded status last week! And this is not even going to mention the significant ground equipment damage they have to deal with. Very unfortunate all around. I hope BO finds a way to keep the timelines.

> Blue origin was _just_ selected to be the first moon lander mission Just a rover [1]. Blue Moon is one of the two lander contractors. But pretty much everyone thinks Artemis is Starship HLS or bust. Does Blue Origin not have another pad? (Did they blow up a pad or a test stand?) [1] https://www.nasa.gov/news-release/nasa-selects-blue-origin-t...

Blue Origin's lunar architecture is designed for a maximum of twelve moon landings per year for the Blue Moon Mk2 without using Orion and the same $4 billion budget per Orion+SLS flight.

SpaceX's architecture requires a second cislunar starship for the return trip. That will mean at most four moon landings per year and even that is optimistic. The large size of Starship makes return trips and lunar refueling really unattractive. If SpaceX wants to compete they will need to build a dedicated cislunar vehicle.

Re: Blue Origin's New Glenn blows up during static fire test

#277

Post by mongol »

jillesvangurp wrote: post #229
hgoel wrote: post #37

Ouch, losing the rocket is unfortunate, but the damage to the launch infrastructure is going to easily mean over a year of repairs. I hope they're going to take this as an opportunity to update the infrastructure from lessons learned from the flights so far, and to be able to support some of their future ambitions (e.g. Jarvis).

It's an understandable but wrong attitude. If you don't have high profile failures like this, you aren't taking enough R&D risk. It's a fiercely ambitious industry and these launch attempts amount to what literally are moon shots. The race is on between various companies and countries as to who gets there first. Boeing is pretty much out of the race at this point. Just too busy navel gazing and lobbying. There's a bi…

What were the high profile failures in the Apollo program that proves your point?

Re: Blue Origin's New Glenn blows up during static fire test

#278

Post by bolangi »

xeonmc wrote: post #118
userbinator wrote: post #113

Does anyone else find it surprising that rockets are a century old[1] and yet still seem to fail spectacularly with amazing regularity, often due to some small flaw? Is it just that they're still relatively niche machines and thus haven't benefited from mass manufacturing improvements? [1] https://en.wikipedia.org/wiki/File:Goddard_and_Rocket.jpg

aerospace is operating at the absolute limit of what can be asked of known materials science

And an unexpected transient load or heat flux can easily exceed material limits, or materials can have flaws. The ability to qualify the materials, components and processes for aerospace use is an achievement in itself.

Re: Blue Origin's New Glenn blows up during static fire test

#279

Post by coarise »

xethos wrote: post #248
GMoromisato wrote: post #133

This is a crushing setback for Blue Origin. I feel for the engineers. They have been the underdogs for so long, but with the recent successful recovery of the New Glenn booster, it finally seemed like they had some bragging rights. Now they're looking at a year minimum before they get back to a regular launch rhythm. The question now is: What went wrong? If they're lucky, it's just a stupid mistake. Maybe an incorrec…

> They even requested access to a ULA building to see if a sniper could have taken a shot at the rocket. > It turned out to be an exotic failure: liquid oxygen had gotten caught inside a buckled liner I gotta say, suspecting "Rival company hired a sniper" before "Dealing with liquid oxygen is very fucking hard and incredibly flammable" feels very Elon

>feels very Elon

why

Re: Blue Origin's New Glenn blows up during static fire test

#280

Post by aaron695 »

xethos wrote: post #248
GMoromisato wrote: post #133

This is a crushing setback for Blue Origin. I feel for the engineers. They have been the underdogs for so long, but with the recent successful recovery of the New Glenn booster, it finally seemed like they had some bragging rights. Now they're looking at a year minimum before they get back to a regular launch rhythm. The question now is: What went wrong? If they're lucky, it's just a stupid mistake. Maybe an incorrec…

> They even requested access to a ULA building to see if a sniper could have taken a shot at the rocket. > It turned out to be an exotic failure: liquid oxygen had gotten caught inside a buckled liner I gotta say, suspecting "Rival company hired a sniper" before "Dealing with liquid oxygen is very fucking hard and incredibly flammable" feels very Elon

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