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fredinno

Independent NASA Safety panel says that SLS/Orion, along with Commerical Crew Development schedule pressure is creating safety issues

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http://spacenews.com/nasa-safety-panel-worries-about-schedule-pressure-on-exploration-programs/

An independent safety panel, the NASA Aerospace Safety Advisory Council has recently published that it has growing concerns over "a continued and unacknowledged accretion of risk" in the SLS/Orion program, caused by schedule pressures and tight funding, and that there is an "apparent erosion of safety" in that program that could "put crews on future missions in jeopardy."

One specific area of concern was the schedule for EM-2 (which has been stated by NASA to likely (70% chance) be delayed to 2022 or 2023), but that NASA is continuing to work to the 2021 date, which has 0 confidence of happening at 2021. The panel observed that NASA appeared to be making "safety trade-offs" to meet that date (though a test flight between EM-1 and EM-2 for SLS Block IB has been confirmed by NASA). The required development of the Exploration Upper Stage, which NASA is building for EM-2, and Orion life support testing were stated to be some of its concerns, along with changes to the heat shield, and "zero fault tolerent" Orion SM systems, such as propellant valves. The panel has suggested NASA keep Orion in LEO during EM-2, mitigating many of the safety risks - calling the current plan to test Orion/SLS in 2 missions (3 once the 'EM-1A' SLS Block IB test flight NASA now needs for EM-2 is approved by the govn't).

Additionally, though SLS/Orion has received more money from Congress than what NASA has requested in recent years, the flat level of funding (the $1 Billion dollar NASA budget increase proposed by Congress has not yet been approved yet) Also, according to the Council, the  budget for SLS/Orion is not layed out "to acheive needed design effort of a major program" (aka lacking direction). Speaking of direction, NASA's current "goals" for SLS/Orion has been critized for lack of detail, despite releasing a new report on how NASA plans to go to Mars and that more detail would do wonders to help it survive.

Additionally, NASA's Commerical Crew Program was also studied by the Council, and has been given a much better view of it compared to previous years- where it was much more critical of it. According to them, there has been a "substantial improvement in openness and interaction"; on the other hand, there are still many challenges ahead, resulting in concerns over NASA accepting more risk, and that there is a "high likelihood of delays to the first test flights". Despite this, NASA has been recommended by the council to continue developing 2 vehicles for that program.

One last thing, Orion now is using tiles instead of a monolithic heat shield. Let's see how this plays out...


Let's hope this does not cause another "Challenger". If it does, at least we have a launch escape system...

Edited by fredinno

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Btw about SpaceX Dragon.

Its mass is ~=10 t (more or less). It has 8 SuperDracos, each 73 kN also used as internal LES.
T/W ratio = 73000 *8 / (10000 * 9.81) ~= 6 g.

Dragon's "pad abort test" description also says about 6 g.

But absolutely all known LES systems (either escape towers, or ejectiing seats) give 12..18 g.
Because on a launchpad you need to run away outside from the explosion wave, while duriing the ascent you need to overcome an insane rocket which still accelerates.

If you divide Falcon thrust by Falcon mass without Dragon (say, it has successfully separated), you can see that with those 6 g the Dragon can overcome the rocket only in the very beginning of every stage working, while they are full of fuel and heavy, Say, the second stage without Dragon in the final of its burning would accelerate with T/W ~15 g.

So, for me it looks like:
in orbit you need 0.5 g
to land you need 2 g
to rescue you need 12..18 g

Dragon has 6 g. I.e too overpowered and heavy for landing, but too weak for rescue.

So, the  Dragon option is even worse than Orion/CST-100 problems.
 

Edited by kerbiloid

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3 hours ago, fredinno said:

Fix the .copm

3 hours ago, kerbiloid said:

...

HOW YOU DARE TO QUESTION SPACE X HERE?? :sticktongue:

I will add another aspect that doesn't feel right, how fast the superdracos work, the jerk? (as the time between you start the motor until it has 100% trust) Because IIRC solid rockets are very fast but liquid motors are not so fast.

I have in mind another question, not only applicable to SpaceX, how much of the cost reduction comes from diminishing the labour rights? Or other manufacturing related costs, like less measurement, less certification? This can affect quality in huge way, and I almost always see that is the first option for mangers wanting to drop production costs.

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The change in heat shield is interesting. I know the cell-filling on Orion was taking some ridiculous number of man-hours. If they change the heat shield, that pretty much voids the reentry test on the one and only test launch of the capsule.

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We'll see how well the SuperDracos work at the next abort test. For now, I'm betting that if a bunch of armchair rocket scientists can spot the potential issues, then the actual rocket engineers at SpaceX have probably thought of them too.

Regarding reduced costs, I have no idea what working conditions in the US are like in general and at SpaceX in particular. So far as I'm aware, most of the cost reduction has come about through good engineering, commonality of components, doing most of their manufacturing in-house and generally setting themselves up as if they hope to actually make a profit on what they're doing.

Quality - yes they had problems with Falcon 1. Off the top of my head though, Falcon 9 has only had a couple of visible issues - and they've flown quite a few of them now in various iterations. I can think of one engine explosion - which didn't result in a loss of vehicle, and one loss of vehicle which was traced to a faulty strut sourced from an outside company. I'm sure there have been other problems along the way - launches don't just scrub themselves - but so far the ethos seems to have been 'scrub rather than 'splode.'

TL: DR, I'm not seeing any obvious signs of poor quality control or corner cutting with flight operations.

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I was pointing based in my real life experience, want a reduction in production cost? first thing they ask is unpaid extra hours, and well looking at simple search you encounter things like this:

http://money.cnn.com/2014/08/13/news/companies/spacex-lawsuits/

http://www.businessinsider.com/elon-musk-email-tesla-employee-2015-5

http://www.ibtimes.com/spacex-lawsuit-alleges-elon-musks-rocket-company-forced-hourly-employees-work-clock-2151993

And then they star to look like the things I see in my life. That kind of ambient creates high rotation of workers, because they get tired of that job and they start to look for another employ, so you don't have many "old" workers, you have lots of new inexperienced workers and a few old ones that are tired of the job and of teaching the new ones.This goes worse in the time, and in the end drops quality in the production or at least in the quality control, like in the last proton failures.

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Employment is a contract between two consenting parties. They have a "right" to find other employment if their current workload bothers them.

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12 hours ago, kerbiloid said:

Btw about SpaceX Dragon.

Its mass is ~=10 t (more or less). It has 8 SuperDracos, each 73 kN also used as internal LES.
T/W ratio = 73000 *8 / (10000 * 9.81) ~= 6 g.

Dragon's "pad abort test" description also says about 6 g.

But absolutely all known LES systems (either escape towers, or ejectiing seats) give 12..18 g.
Because on a launchpad you need to run away outside from the explosion wave, while duriing the ascent you need to overcome an insane rocket which still accelerates.

If you divide Falcon thrust by Falcon mass without Dragon (say, it has successfully separated), you can see that with those 6 g the Dragon can overcome the rocket only in the very beginning of every stage working, while they are full of fuel and heavy, Say, the second stage without Dragon in the final of its burning would accelerate with T/W ~15 g.

So, for me it looks like:
in orbit you need 0.5 g
to land you need 2 g
to rescue you need 12..18 g

Dragon has 6 g. I.e too overpowered and heavy for landing, but too weak for rescue.

So, the  Dragon option is even worse than Orion/CST-100 problems.
 

Well, at least that can allow for extra (emergency)delta V, as proposed for the Orion LES in the consteallation days.

39 minutes ago, kunok said:

I was pointing based in my real life experience, want a reduction in production cost? first thing they ask is unpaid extra hours, and well looking at simple search you encounter things like this:

http://money.cnn.com/2014/08/13/news/companies/spacex-lawsuits/

http://www.businessinsider.com/elon-musk-email-tesla-employee-2015-5

http://www.ibtimes.com/spacex-lawsuit-alleges-elon-musks-rocket-company-forced-hourly-employees-work-clock-2151993

And then they star to look like the things I see in my life. That kind of ambient creates high rotation of workers, because they get tired of that job and they start to look for another employ, so you don't have many "old" workers, you have lots of new inexperienced workers and a few old ones that are tired of the job and of teaching the new ones.This goes worse in the time, and in the end drops quality in the production or at least in the quality control, like in the last proton failures.

Younger workersare also cheaper. Currently, SpaceX can get awaywith it because the hype is causing a huge amount of workers to line up to be hired, but that will likely end in a few years as SpaceX's operations become routine. I think reuse will have to make up for the costs of older employees, reducing worker turnover, etc, so the net cost loss is minimal. The current spaceX buisness model isn't sustainable in the long term.

7 hours ago, kunok said:

Fix the .copm

HOW YOU DARE TO QUESTION SPACE X HERE?? :sticktongue:

I will add another aspect that doesn't feel right, how fast the superdracos work, the jerk? (as the time between you start the motor until it has 100% trust) Because IIRC solid rockets are very fast but liquid motors are not so fast.

I have in mind another question, not only applicable to SpaceX, how much of the cost reduction comes from diminishing the labour rights? Or other manufacturing related costs, like less measurement, less certification? This can affect quality in huge way, and I almost always see that is the first option for mangers wanting to drop production costs.

Fixed the .copm

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They should test the life support on EM-1.Their useing a tiled heat sheild? cool! But, we saw how that worked out...  Orion shouldn't still be in development.They should take advantage of what they started with CCDEV and use Dragon.

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5 minutes ago, Emperor of the Titan Squid said:

They should test the life support on EM-1.Their useing a tiled heat sheild? cool! But, we saw how that worked out...  Orion shouldn't still be in development.They should take advantage of what they started with CCDEV and use Dragon.

Yeah, Dragon would need to go through its own development phase after Dragon V2 to create a BEO dragon, Dragon V3 (it's not capable of long duration BEO missions, for example, a larger service module would be needed, something Dragon is not designed to, along with propellant transfer between the CM and SM.) Larger Solar panels would likely be needed for a higher power usage, not to mention Dragon has much less available space (and thus downmass and available supplies), thus neeeding a 2nd crewed module on its top to be used for the longer duration missions, which need more space and supplies.

The end result is that it's better to just use Orion. Dragon V2 will be completed by 2017, and god knows how long a V3 would take. Orion is going to be complete by 2018, the hiatus to 2021 is due to SLS Block IB development and human-rating.

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33 minutes ago, tater said:

Employment is a contract between two consenting parties. They have a "right" to find other employment if their current workload bothers them.

This is a large part of the reason that the SLS exists.  The shuttle needed an army of technicians to service it.  Once it was canceled, there were only so many jobs looking for "twenty years of super-high-tech tile laying and a TS/Poly clearance".

It isn't as much a problem now due to the huge amounts of people waiting in line for space-x jobs and the presumed high-quality jobs waiting at Apple and Google for  those burnt out at Space-x.  It becomes more of an issue when the lines dwindle and companies insist on bringing in H1-Bs due to having a worse reputation to work at than Amazon.

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23 minutes ago, wumpus said:

This is a large part of the reason that the SLS exists.  The shuttle needed an army of technicians to service it.  Once it was canceled, there were only so many jobs looking for "twenty years of super-high-tech tile laying and a TS/Poly clearance".

It isn't as much a problem now due to the huge amounts of people waiting in line for space-x jobs and the presumed high-quality jobs waiting at Apple and Google for  those burnt out at Space-x.  It becomes more of an issue when the lines dwindle and companies insist on bringing in H1-Bs due to having a worse reputation to work at than Amazon.

I actually took my truck driving class with one of those guys. He was in his 50s, spent literally his entire life outside of the military gluing the tiles on to the space shuttle, then one day, he was out of a job with no usable experience.

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On 27.2.2016 at 8:46 AM, kerbiloid said:

Btw about SpaceX Dragon.

Its mass is ~=10 t (more or less). It has 8 SuperDracos, each 73 kN also used as internal LES.
T/W ratio = 73000 *8 / (10000 * 9.81) ~= 6 g.

Dragon's "pad abort test" description also says about 6 g.

But absolutely all known LES systems (either escape towers, or ejectiing seats) give 12..18 g.
Because on a launchpad you need to run away outside from the explosion wave, while duriing the ascent you need to overcome an insane rocket which still accelerates.

If you divide Falcon thrust by Falcon mass without Dragon (say, it has successfully separated), you can see that with those 6 g the Dragon can overcome the rocket only in the very beginning of every stage working, while they are full of fuel and heavy, Say, the second stage without Dragon in the final of its burning would accelerate with T/W ~15 g.

So, for me it looks like:
in orbit you need 0.5 g
to land you need 2 g
to rescue you need 12..18 g

Dragon has 6 g. I.e too overpowered and heavy for landing, but too weak for rescue.

So, the  Dragon option is even worse than Orion/CST-100 problems.
 

Acceleration is well known to anybody involved, yes weight will be around 10 ton fully loaded, you will eject with the trunk and the unpressurized cargo. 
It must be an agreement that 6g is enough, an first stage at separation + second stage should not reach 6g even without the dragon, second stage weight over 50 ton so 5x heavier than the dragon, now add first stage weight. 
For end of second stage burn you would have dropped an escape tower anyway.
Mostly leaving the pad abort test who was done and is accepted. 
My guess is that the 12g give an small bonus but is mostly used as its cheap to add more trust to solid fuel rockets, its the dV who is expensive.
 



 

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That's what inevitably happens. 

Perhaps the only thing worse than drowning is to drown in beauracracy.

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