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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

#171

Post by _moof »

JumpCrisscross wrote: post #75
generuso wrote: post #21

It is not clear what "full duration static fire" means, but if the stage was fully fueled, the fuel tank would have contained 1000 tons of methane. The heat of combustion of methane is 55 MJ/kg. TNT equivalent is defined as 4.2 MJ/kg. In terms of heat output (not blast or other effects) this would have been equivalent to 13 kilotons of TNT. The first atomic bomb had yield of 20 kt TNT, of which about half was in heat…

> not clear what "full duration static fire" means You fire the rocket as if it’s going to space, but you keep it on the pad. (From the engine’s perspective, it did a full launch.)

From the industry: I would expect to hear "mission duty cycle" in that case. "Full duration" doesn't have a consistent meaning (a fact which is sometimes used to the marketing team's advantage).

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

#172

Post by block_dagger »

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…

[flagged]

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

#173

Post by avmich »

bombcar wrote: post #114
anotherevan wrote: post #87

Also known as a Rapid Unscheduled Disassembly in engineer speak.

Technically I think this was a Rapid Tank Emptying. RUD implies launch.

I don't think RUD implies launch. It can happen with an engine alone, without rocket.

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

#174

Post by logicallee »

perlgeek wrote: post #162
baq wrote: post #161

On the scale of bad 1-10 where 10 is the absolutely worst case this is a 12 easily . (Elon’s strategy of blowing up smaller versions of their rockets more or less deliberately doesn’t sound so insane in the light of this.)

I'd say on a scale of bad 1-10, 9 and 10 are reserved for incidents that cause loss of human life. YMMV.

yeah if you want to put it in the best light in terms of 9/11's this is zero 9/11's of casualties. Not how I'd judge it.

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

#175

Post by Buttons840 »

mandevil wrote: post #93
mholt wrote: post #89

Is it normal to load ALL the propellant when doing a static fire? (I presume that's the case, anyway, given the sheer magnitude of the kaboom.) I know a WDR typically would, but I don't think they perform an ignition for those.

In September 2016 almost exactly the same thing happened to a Falcon 9 at the Cape, also on a static fire. New Glenn is bigger, so bigger bang, but pretty much exactly the same thing. Off the top of my head, I recall in SpaceX's case it was a helium tank failure- a helium tank weld failed and the helium tank itself shot through the cryogenic oxygen, hit the far wall, and gave off a spark. But that sort of failure is…

How do they determine the cause of failure in a things like this?

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

#176

Post by kqr »

Polizeiposaune wrote: post #123
mholt wrote: post #89

Is it normal to load ALL the propellant when doing a static fire? (I presume that's the case, anyway, given the sheer magnitude of the kaboom.) I know a WDR typically would, but I don't think they perform an ignition for those.

The weight of the propellant helps hold the rocket on the pad during the test fire, reducing how much force the hold-downs need to exert to keep the rocket on the pad, and stressing the rocket's structure in the same way it will be stressed at launch. Test fires with a near-empty rocket would put considerably more force on the pad's hold-downs and the corresponding parts of the rocket's structure. Blue also had a fue…

Right. The forces these things produce are massive. I only know the specifics for the Space Shuttle, but when it is at full liftoff thrust (liquid and solid boosters) there's just no way to keep it leashed to Earth. It's going up whether you want to or not.

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

#177

Post by pennomi »

pfdietz wrote: post #169
l1tany11 wrote: post #121

Earlier quoted context omitted.

Simplest explanation comes from Tory Bruno: they design with a factor of safety just above 1. 1.1 to 1.25. This is one of the reasons they wait for good weather to launch… they are trying to maximize payload. Also until recently, it’s been sort of a vicious cycle: rocket is very exquisite and expensive, so spacecraft needs to last longer and thus gets more exquisite and expensive, etc. Have you seen how many issues r…

I believe the safety factors in Falcon 9 are 1.4. NASA credited SpaceX with using safety factors larger than normal for aerospace.

Surely reusability requires higher margins than ever needed before.

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

#178

Post by wahern »

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…

Crushing only because their cadence is so slow compared to SpaceX. Their process seems much closer to the highly risk averse methodology of traditional incumbents than to SpaceX's style. Failure becomes a self-fulfilling prophecy.

Rockets are ridiculously complex. Slow-and-steady wins the race makes sense for many individual components, depending on how well understood the problem domain is, and your ability to rigorously model things. But if you take that approach when testing all the thousands of components together, which is simply just too complex to exhaustively model[1], you'll never get anywhere. You have to be prepared to not only break some eggs in epic fashion, but to break many as quickly as you can, so you can parallelize your problem solving and iterate faster.

[1] At least without a large multiple in time and monetary expenditure that ends up costing more than even the US (government and private capital combined) is prepared to spend.

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

#179

Post by oconnor663 »

arjie wrote: post #167
oconnor663 wrote: post #135

Earlier quoted context omitted.

The vehicle is designed to hold all that fuel, plus whatever payload it carries on top, but it's not designed to have heavy loads attached to it in any other way. Rockets are so intensely optimized for weight that sometimes they're barely strong enough to stand upright if you fuel them the wrong way: https://www.youtube.com/watch?v=imkdz63agHY .

That's a great video! Thank you for sharing it. A rocket is more like a soda can than a building but it's hard to relate when you see such a massive object!

You can see a similar effect after the explosion at the end of last week's Starship test flight. If you look at where the flames are coming out after the first fireball clears, it kind of pancakes under its own weight there: https://www.youtube.com/live/Zi2SU98BAD8?t=5735s

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

#180

Post by malux85 »

block_dagger wrote: post #172
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…

[flagged]

Much more likely is that it would hallucinate a plausible sounding but incorrect answer and send intermediate and junior engineers on a wild goose chase
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