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Blue Origin has hot fired its BE-4 rocket engine for the first time

arstechnica.com

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Re: Blue Origin has hot fired its BE-4 rocket engine for the first time

#41

Post by JumpCrisscross »

golfer wrote: post #24
mabbo wrote: post #9

Earlier quoted context omitted.

Just imagine what things would look like if SpaceX has a serious failure again. It could drop them back six months, and Blue Origin would get that much closer. Must be a really good motivator for SpaceX.

Maybe it's a good motivator for SpaceX, but let's look at the macro picture. Blue Origin has zero commercial flights in its history. It is far behind SpaceX. But if BO displays operational expertise and can execute on its plans, it will be an exciting competitor. Then again, if BO has some setbacks like SpaceX has had (delays, launch failures, etc) then it might not shake up the industry as much as we hope.

Tortoise and hare. Blue Origin spends more time designing and testing; SpaceX producing and selling. I tend to default to the latter strategy in most markets, but aerospace is different. The results are and will be interesting.

Re: Blue Origin has hot fired its BE-4 rocket engine for the first time

#42

Post by tim333 »

trothamel wrote: post #6
faitswulff wrote: post #4

A few frames of the video caught my eye: https://screenshots.firefox.com/eOm06NUSg0CSkb1a/arstechnica... It looks like there's some sort of harmonic wave in the blast. Does anyone have any insights on why the design would result in that?

I believe those are Mach/Shock diamonds, which are common in rocket engine exhaust. It wouldn't surprise me if the propellant and the time of the test made them more visible. https://en.wikipedia.org/wiki/Shock_diamond

As also seen on page 2 of "Ignition" with page 3 showing some other interesting rocket effects. http://library.sciencemadness.org/library/books/ignition.pdf

Re: Blue Origin has hot fired its BE-4 rocket engine for the first time

#43

Post by shmerl »

philipkglass wrote: post #39
jofer wrote: post #31

Earlier quoted context omitted.

Wait, I'm confused... LNG is pure methane. Are there rockets that use methane that aren't storing it as a liquid? I would have to guess that any rocket using methane would pressurize it enough to be in liquid form for storage, anyway. Surely they wouldn't use methane in a gas state... It would take up far too much space to be practical.

LNG is 85-95% methane, typically, with ethane making up most of the rest. It contains small amounts of propane and butane. I hadn't known that SpaceX was using a special grade of ~100% liquefied CH4 as nickik says above. EDIT: shale gas is richer in ethane and higher hydrocarbons than traditional sources of natural gas. Maybe SpaceX is sticking to 100% methane just so they don't have to ponder variability of composit…

Methane can be synthesized from CO2 and hydrogen. More complex hydrocarbons are way more difficult to produce. So pure methane based engine is a better method for using on other planets.

Re: Blue Origin has hot fired its BE-4 rocket engine for the first time

#44

Post by greglindahl »

nickik wrote: post #18
vermontdevil wrote: post #15

Biggest thing to me is the use of fuel here. Liquified natural gas has a lot of benefits. Simpler pressurization system, less soot etc The future is exciting.

One of the price advantages that Blue has over SpaceX is that they will fly with LNG rather then pure methane. Edit: Will New Glenn also not use a third gas for pressurisation? Like BFR?

When you liquefy natural gas, ethane and methane liquefy at different times, so it's relatively easy to purify methane. I don't know the price difference, do you?

Re: Blue Origin has hot fired its BE-4 rocket engine for the first time

#45

Post by greglindahl »

iamcreasy wrote: post #38

Anybody knows what's special about this engine besides it being able produces more thrust than SpaceX's Raptor engine?

The main special thing is that it runs on methane fuel, which has less sooting than kerosene engines. That makes it easier to reuse them. SpaceX is headed in the same direction with their Raptor engine, intended to power the BFR, and Europe is working on Prometheus, which might ship in the mid to late 2020s.

Re: Blue Origin has hot fired its BE-4 rocket engine for the first time

#46

Post by greglindahl »

JumpCrisscross wrote: post #41
golfer wrote: post #24

Earlier quoted context omitted.

Maybe it's a good motivator for SpaceX, but let's look at the macro picture. Blue Origin has zero commercial flights in its history. It is far behind SpaceX. But if BO displays operational expertise and can execute on its plans, it will be an exciting competitor. Then again, if BO has some setbacks like SpaceX has had (delays, launch failures, etc) then it might not shake up the industry as much as we hope.

Tortoise and hare. Blue Origin spends more time designing and testing; SpaceX producing and selling. I tend to default to the latter strategy in most markets, but aerospace is different. The results are and will be interesting.

You can say that about any pair of companies where one has a shipping product and the other does not.

Re: Blue Origin has hot fired its BE-4 rocket engine for the first time

#47

Post by greglindahl »

nickik wrote: post #14
mabbo wrote: post #9

Earlier quoted context omitted.

Just imagine what things would look like if SpaceX has a serious failure again. It could drop them back six months, and Blue Origin would get that much closer. Must be a really good motivator for SpaceX.

Why would a Falcon 9 failure set the BFR back six months? The teams working the BFR parts are probably not strongly involved and could just continue working. It would set them back somewhat, but I don't see why it would be that long.

"Return to flight" activities appear to be a big distraction for the entire company, for example the previous 2 failures caused Falcon Heavy to slip a lot.

Re: Blue Origin has hot fired its BE-4 rocket engine for the first time

#48

Post by toomuchtodo »

ape4 wrote: post #20
vermontdevil wrote: post #15

Biggest thing to me is the use of fuel here. Liquified natural gas has a lot of benefits. Simpler pressurization system, less soot etc The future is exciting.

If this new rocket turned out better, I suppose SpaceX could license the tech.

Musk has mentioned SpaceX doesn't patent its innovations because you're competing against nation-states who don't have to follow the rules.

Re: Blue Origin has hot fired its BE-4 rocket engine for the first time

#49

Post by JumpCrisscross »

greglindahl wrote: post #46
JumpCrisscross wrote: post #41

Earlier quoted context omitted.

Tortoise and hare. Blue Origin spends more time designing and testing; SpaceX producing and selling. I tend to default to the latter strategy in most markets, but aerospace is different. The results are and will be interesting.

You can say that about any pair of companies where one has a shipping product and the other does not.

> You can say that about any pair of companies where one has a shipping product and the other does not

Not necessarily. Rabbits move fast and break things; tortoises plod along deliberately and slowly. This applies to Blue Origin because they’re being deliberately slow and thoughtful, versus lazy or incompetent. Theranos or Magic Leap, for instance, are not tortoises.

Re: Blue Origin has hot fired its BE-4 rocket engine for the first time

#50

Post by nbanks »

valuearb wrote: post #34
Nokinside wrote: post #10

Earlier quoted context omitted.

It would be interesting to see how the market share affects the profits and how these two companies plan to compete in long term. If Blue Origin and SpaceX compete in the same segment and divide the market, development and manufacturing costs per launch will increase for both. Assuming each will price the launch price so low that they get roughly 50 percent of the market they would get without the other, both lose ha…

A 3% profit margin isn’t modest, it’s catastrophic. With a their heavy capital requirements and massive technology lead they should be banking 30%. 3% says please shut us down first time we have a bad year.

However spacex could easily survive off 3% profit for now, as long as they still keep collecting all their used rockets. I only remember them launching one used rocket so far which was successful, and presumably they'll work out any remaining glitches and start using the others.
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