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Blue Origin Thread (merged)


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9 minutes ago, Tullius said:

They are probably thinking that the risk of the SM being damaged is sufficiently low that it is not worth carrying the LES any further. Also bear in mind that in the case of Apollo, they turned the automatic abort system off after reaching 30km of altitude. So they expected that any failure occuring afterwards would be harmless enough that manual abort would be sufficient.

Nonetheless, not relying in the SM surviving is certainly advantageous.

I think it is the latter. In the wikipedia article about Apollos abort modes, abort mode 1a is said to be similar to a pad abort.

Yes upper stage burn is less energetic, you also has time to do something. 
On the other hand since Falcon 9 problems has been upper stage I would be happy I had the trunk between me and it and not having the service module engine right over upper stage like other manned launchers. 

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And it's now official;

http://www.spacex.com/news/2016/09/01/anomaly-updates

Quote

December 7, 10:30am EDT

We are finalizing the investigation into our September 1 anomaly and are working to complete the final steps necessary to safely and reliably return to flight, now in early January with the launch of Iridium-1. This allows for additional time to close-out vehicle preparations and complete extended testing to help ensure the highest possible level of mission assurance prior to launch.

 

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1 hour ago, Kryten said:

As I understand the liquid helium froze the liquid oxygen. This is not an problem with normal liquid oxygen but the supercooled one used by spacex is close to freezing point and would freeze easy. Did anybody see this one? 
I don't understand how freezing oxygen around the helium tank or pipes could cause an explosion, most liquids except water shrink then freezing. 
I guess its some chemical reaction, composites and pure oxygen sounds like an dangerous combination.

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On 12/3/2016 at 4:36 AM, Nibb31 said:

It's always possible. The problem is how much are you ready to spend on isolating the root cause ?

After Columbia, NASA spent millions of dollars on studies and tests. They tore down the other shuttles and did destructive testing on various components. They interviewed hundreds of people. They analysed thousands of pages of documents and procedures. The even built a special cannon to shoot supersonic blocks of frozen foam at RCC panels.

If they had an unlimited budget and unlimited time, SpaceX could cycle test other cores through the same procedures to pinpoint the cause. They could verify their hypothesis by pushing hardware to its limits during destructive testing. But SpaceX is a private corporation that doesn't operate in the same economical or legal environment as NASA. They are on a limited budget and they have economical pressure to resume flights ASAP.

Point of fact...NASA was critized for the lack of safety testing due to poor funding and shrinking staff necessary to get such task accomplished. CAIB cite that as a contributing factor to the Columbia disaster. In fact NASA never tested whether the RCC panels or any other component of the Shuttle's thermal protection system could withstand damage sustained by debris shedding until after the loss Columbia during the post-disaster investigation.

In fact it was surprising to me that the most obvious solution to the bipod ramp shedding issue was never pursued until after Columbia's destruction...the elimination of the ramps altogther! And yet for years NASA never pursued eliminating the shedding issue; simply considering such events as "normal" (Another contributing factor per the CAIB report).

Edited by Exploro
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It's basically the same like Challenger - a system with certain flaws won't go well until they actually fixed it. Which, in case of foam shedding, is close to impossible - all they can do is reducing the risks.

7 hours ago, magnemoe said:

As I understand the liquid helium froze the liquid oxygen. This is not an problem with normal liquid oxygen but the supercooled one used by spacex is close to freezing point and would freeze easy. Did anybody see this one? 
I don't understand how freezing oxygen around the helium tank or pipes could cause an explosion, most liquids except water shrink then freezing. 
I guess its some chemical reaction, composites and pure oxygen sounds like an dangerous combination.

Maybe the metals materials went off under the cold temperature and high pressure ?

As I said, they didn't made it to handle them - why still do it ?

EDIT : But in any case, this shall be good science, no ?

Edited by YNM
clarify...
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7 hours ago, magnemoe said:

As I understand the liquid helium froze the liquid oxygen. This is not an problem with normal liquid oxygen but the supercooled one used by spacex is close to freezing point and would freeze easy. Did anybody see this one? 
I don't understand how freezing oxygen around the helium tank or pipes could cause an explosion, most liquids except water shrink then freezing. 
I guess its some chemical reaction, composites and pure oxygen sounds like an dangerous combination.

As I understand it, the LOX was close enough to its freezing point that the even colder helium being pumped into the composite tank caused some to freeze between the individual carbon fibers overwrapping it. As the tank came up to pressure, it expanded just slightly, but enough to squeeze the solid oxygen amongst the fibers. Mashing things together with oxygen at high pressure has a rather deleterious effect on their ability to maintain existence, i.e., things exploded. This burst the helium tank, which instantly released high presssure helium into the LOX tank, causing IT to instantly burst and mix with the kerosene as that tank, too, burst. 

 

I'm once again gonna take SpaceX at face value, here. They're doing things that have never been done before with this deep cryo stuff. There's going to be a learning curve to figure out what they can and cannot do with it. The same goes for virtually any reactive chemical. If a different fueling procedure is what's needed to avoid the formation of solid O2, why is that such a radical thing?

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1 hour ago, Elthy said:

Not surprising, i hope they take their time.

I wonder where SpaceX gets the neccessary life-support system. Do they develope that themself or are other companys involved?

They're doing a lot of work inhouse, as usual, but Paragon Space Development Corporation was/is heavily involved. They brought them onboard as soon as the Commercial Crew program started.

(They already helped build cargo Dragon's environmental controls, so the choice was not surprising at all)

 

Edited by Streetwind
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On 12/7/2016 at 5:29 PM, YNM said:

It's basically the same like Challenger - a system with certain flaws won't go well until they actually fixed it. Which, in case of foam shedding, is close to impossible - all they can do is reducing the risks.

The real system failure was the attitudes at NASA. Those never changed after Challenger, and so Columbia happened. It was the EXACT same issue -- safety issues that had happened again and again were normalized precisely because of how often they had happened.

Let me give an example from my own personal life. I was doing a lapping day (driving my car on a racetrack) in the rain. There was a puddle of standing water on the track in the middle of the main straight. I went through it lap after lap and I felt the car hydroplane. But I was able to keep control. So instead of backing off through there, I kept picking up my pace. Every time the car would shimmy. The next lap I would drive a little faster. Finally one side of the car completely lost all grip. The other side of the car was still in contact, and I had a "limited slip" differential, meaning I still had power to the side that had traction. The car *immediately* spun. I bounced it off of one concrete wall, then all the way across the track and off of another concrete wall.

Why? Because instead of taking the warning signs as actual warnings, I took them as information that the problem was not severe. NASA did the exact same thing. The more burnthrough they had on the SRBs, the more they thought burnthrough was not a risk. The more foam that impacted the orbiter, the more they thought foam was not a risk. The more times I hydroplaned through that puddle, the more I thought hydroplaning was not a risk.

See how that works?

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I just had to delete a few posts with political content. Not that I am ever happy making so, but there are very good reasons behind forum rule 2.2.b. My hope is such political content won't come up again, please do your best to keep by the rules.

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On 13/12/2016 at 0:44 PM, kerbiloid said:

But Red Dragon is still happening, right?

BTW why do they have the helium tank problem with the upper stage but not with the first one? is it because the tanks in the second stage are cramped together to a degree they have direct contact with each other? If that's the case can't they simply give it some more space, or something? I guess that would increase the mass, but would also be a way to maybe solve this issue?

Edited by Veeltch
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12 minutes ago, Veeltch said:

But Red Dragon is still happening, right?

BTW why do they have the helium tank problem with the upper stage but not with the first one? is it because the tanks in the second stage are cramped together to a degree they have direct contact with each other? If that's the case can't they simply give it some more space, or something? I guess that would increase the mass, but would also be a way to maybe solve this issue?

A whole lotta nuthin' is happening until they get this fueling issue stamped out and get back to flying. Although I did hear they lost a FH customer to Ariane recently, so maybe that keeps the LV for Red Dragon available even with the delays.

We've only seen ONE instance of this helium tank thing, maybe it could theoretically affect first stages too, but like always SpaceX is doing something never done before. It may take time to get the bugs out. As I understand the issue, a different fueling procedure may be all that's needed. And they need to be REALLY sure about that. 

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18 hours ago, insert_name said:

Welp looks like crew dragon has been postponed to 2018 :(

https://spaceflightnow.com/2016/12/13/spacexs-first-crewed-launch-

Good article. In the comments section of that article, there's a link to an even better article: http://www.parabolicarc.com/2016/12/13/year-wait-nasa-report-falcon-9-failure-2015/

44 minutes ago, CatastrophicFailure said:

We've only seen ONE instance of this helium tank thing

Actually, both failures were related to the helium system, but the blame for the first failure was pinned on a strut securing the helium COPV. NASA still isn't 100% sure that that really was the cause (see above linked article), especially after the second failure. Remember, these things are sitting in LOx that is near freezing, instead of near boiling, which is a new thing. Does anyone recall if the CRS-7 was using super-chilled propellants?

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20 minutes ago, StrandedonEarth said:

Does anyone recall if the CRS-7 was using super-chilled propellants?

No, it was not. The only similarity between the two is that they involved the helium tank. What actually failed is completely different. I still don't see how it's possible to be 100% sure of that first failure when all of your physical evidence is at the bottom of the ocean. 

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13 hours ago, CatastrophicFailure said:

 I still don't see how it's possible to be 100% sure of that first failure when all of your physical evidence is at the bottom of the ocean. 

They can get livestream back, I suppose engineering data shall be in as well.

On 12/15/2016 at 3:22 PM, mikegarrison said:

The real system failure was the attitudes at NASA. Those never changed after Challenger, and so Columbia happened. It was the EXACT same issue -- safety issues that had happened again and again were normalized precisely because of how often they had happened.

(great lessons of track days)

Why? Because instead of taking the warning signs as actual warnings, I took them as information that the problem was not severe. NASA did the exact same thing. The more burnthrough they had on the SRBs, the more they thought burnthrough was not a risk. The more foam that impacted the orbiter, the more they thought foam was not a risk. The more times I hydroplaned through that puddle, the more I thought hydroplaning was not a risk.

See how that works?

(sorry, typing from mobile here)

When Challenger lifted off for it's last mission, the engineers are all having goosebumps. When Columbia was struck and nothing was done, the same happens.

Certainly they didn't hear them or something. But, eh, perhaps the mods won't be pleased of this...

I have to say that it's more likely that SpaceX is pushing off those engineering limits. They are entering Science! section now. But I don't want yet another Apollo 1/Challenger/Columbia again.

Edited by YNM
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On 12/7/2016 at 8:29 PM, YNM said:

It's basically the same like Challenger - a system with certain flaws won't go well until they actually fixed it. Which, in case of foam shedding, is close to impossible - all they can do is reducing the risks.

Note that NASA originally grounded Columbia (at least until Challenger), which had tiles (that kept coming off) and was easily the most vulnerable to shedding.  While I suspect that Columbia was grounded due to the cost to replace those tiles, they certainly had to be aware that each missing tile represented a risk of the danger that ultimately doomed Columbia.

Grounding Columbia didn't fix foam shedding, but at least it eliminated the biggest danger it represented.

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15 hours ago, CatastrophicFailure said:

No, it was not. The only similarity between the two is that they involved the helium tank. What actually failed is completely different. I still don't see how it's possible to be 100% sure of that first failure when all of your physical evidence is at the bottom of the ocean. 

Yes, know it was an helium tank issue and they know the struts was way below require strenght, not much more. 

Of topic what is your thumbnail/ avatar? I have thought it was Royal air Morocco but it looks totally different. http://image.airlineratings.com/logos/ram_be.gif

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On 15/12/2016 at 9:22 AM, mikegarrison said:

The real system failure was the attitudes at NASA. Those never changed after Challenger, and so Columbia happened. It was the EXACT same issue -- safety issues that had happened again and again were normalized precisely because of how often they had happened.

Let me give an example from my own personal life. I was doing a lapping day (driving my car on a racetrack) in the rain. There was a puddle of standing water on the track in the middle of the main straight. I went through it lap after lap and I felt the car hydroplane. But I was able to keep control. So instead of backing off through there, I kept picking up my pace. Every time the car would shimmy. The next lap I would drive a little faster. Finally one side of the car completely lost all grip. The other side of the car was still in contact, and I had a "limited slip" differential, meaning I still had power to the side that had traction. The car *immediately* spun. I bounced it off of one concrete wall, then all the way across the track and off of another concrete wall.

Why? Because instead of taking the warning signs as actual warnings, I took them as information that the problem was not severe. NASA did the exact same thing. The more burnthrough they had on the SRBs, the more they thought burnthrough was not a risk. The more foam that impacted the orbiter, the more they thought foam was not a risk. The more times I hydroplaned through that puddle, the more I thought hydroplaning was not a risk.

See how that works?

Making a rocket safe costs money, lots of money, that SpaceX doesn't want to spend.

For the Space Shuttle, you are rightfully pointing out that they didn't pay enough attention. But that was because the Space Shuttle absolutely needed the highest possible reliability, since everything besides a minor failure would result in a catastrophe.

For you, losing your car on the racetrack, was a catastrophe too, because you only had one car. But if you are a race driver, if you don't drive like that, pushing the car to the point where you risk losing it, you won't win any races. And that is no problem, because your team provides you with spare cars for the subsequent races.

And that is exactly what SpaceX is doing: For an unmanned rocket, having an expected reliability of 99% is sufficient. So you don't spend a single cent more than what is needed to get to those 99%. Changing the filling procedure might not solve the underlying problem, but they expect it to be sufficient to get to the desired reliability value. If not, they can still change it later on.

And for the man-rated version of Falcon 9, you always have the LES to save the crew in case of a booster failure. So no need to aim for the same reliability as the Space Shuttle. But still, 99% reliability might not be deemed sufficient and so SpaceX probably needs to come up with a strategy to increase the reliability. And I wouldn't be surprised if that means that Falcon 9 will be man-rated only for the first flight of a booster, while refurbished ones won't be safe enough for crewed flight, due to the costs involved in checking every single system on a flown booster for its safety.

Edited by Tullius
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