SpaceX And/Or Rocketry In General

Anonymous

A very cool short

A very cool short clip

[EDIT] redefines "looking back"

David S
David S
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RE: RE: So assuming this

Quote:
Quote:
So assuming this is confirmed as the cause then the fix is straight forward at least : make and test a stronger strut(s).

As a former design engineer, and also a former factory reliability manager, and a yield analyst, I'd say they will (should) spread a broader net.

First, regarding this failure itself: Was the stress on the strut improperly understood in setting the design requirements? If not, was it misdesigned to meet the requirement. If allegedly all that was right but this sample was mis-manufactured, how did that come to pass, and how did it escape notice?

As you say, fixing the strut is probably straightforward. But the really tough, and really essential part, is appropriately propagating the resulting searchlight beam of suspicion around the rest of the design and manufacturing. If you carry this too far, you will never launch again. But unless carried on with adequate diligence, there is a strong chance there is another lurking problem, lulling you to complacency by almost twenty serial successes, waiting to fail then next time you are two sigma on the bad side of natural manufacturing variation.

As a design engineering manager, I used to call this killing off the brothers, sisters, aunts, and uncles, and nth cousins mth removed of the problem one had just detected. It was a bit hard to motivate people to look--though once they found something, it got a bit easier.


And sometimes there isn't any single failure, it's a whole series of minor things that were overlooked and all have to go wrong in a certain sequence for the whole system to fail. (I'm sure you all know I'm referring to Apollo 13.)

David

Miserable old git
Patiently waiting for the asteroid with my name on it.

archae86
archae86
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RE: In the relatively

Quote:
In the relatively near-term there is scheduled a Progress delivery with July 3 launch, and an HTV (Japanese) delivery with August 16 launch. HTV is big (about 16,000 pounds useful cargo). Now if that one fails, things will look much bleaker


In rocketry as elsewhere, success often gets a tiny fraction of the publicity accorded to failure. I actually did not spot any news in the general press--of which I read more widely than most--that the Japanese August launch did indeed succeed until I read about it in my copy of Aviation Week yesterday.

Somehow what I understood to be 16,000 pounds of cargo turned into 9,500. But it included lots of water, and quite a bit of other supplies.

Sure, they are still missing some individual items they really wanted (e.g. a docking fixture, for which the replacement actually needs to be fabricated), but crew support supplies have greatly improved depth.

Getting back a little closer to the launch topic of this thread, a Wall Street Journal article dated September 1 quotes SpaceX President Gwynne Shotwell as saying that a next launch is at least a couple of months down the road.

Further it quotes her as saying that the company is conducting comprehensive surveys looking for quality problems throughout their supply chain, and also has a system of "buddy checks" internally with engineers having their work reviewed by another.

This all seems somewhat consonant with the corporate adjustment called for by Elon's comment that they probably were no longer sufficiently paranoid.

My personal guess is sometime in the first half of 2016 for next ISS launch, though they might well put up something with a higher failure tolerance sooner. I also guess Heavy won't make it up until 2017, though the party line at the moment is 2016.

I'm still a very big fan of these people, and the impact they have already had on space launch affairs generally. But no one is bullet proof.

Anonymous

RE: I'm still a very big

Quote:
I'm still a very big fan of these people, and the impact they have already had on space launch affairs generally. But no one is bullet proof.

I too support SpaceX and their efforts. Getting back on the horse after it has tossed you off is difficult. I am sure that Musk and the entire engineering team wants to be sure that they have run the checklist thoroughly.

I had searched for the "next launch" but was not able to find anything specific. I don't know if that means they don't have a complete handle on the last
anomaly or if they are just being over cautious. In either case I am sure that can get it done. Will get it done.

I watched the last Soyuz launch. Just brute horsepower. What a workhorse it has been.

David S
David S
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Elon Musk was on The Late

Elon Musk was on The Late Show With Stephen Colbert (episode 2) last night. He said he expects to be launching people to the ISS in two years.

David

Miserable old git
Patiently waiting for the asteroid with my name on it.

Mike Hewson
Mike Hewson
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SpaceX's responses to their

SpaceX's responses to their problems are quite mature. Paranoia works. This sociological aspect can be a greater challenge than the technical bits. We all everyday have a hundred things that compete for attention and can degrade judgement and cognitive performance. So often the first order of the day is to get your own head right, but without descending into analysis-paralysis. That tension between activity and preparation is age old. Planning and protocol are defenses against that, but of course are a task of their own to produce and ( recursively ) come with similar failings.

[pretentious aside] If I was running SpaceX I would have some "roving suspicious b******s" assessing design aspects ( not employee performance ) ie. Devil's Advocates. Their job would be to line up apparently unrelated slices of Swiss cheese and see if there is a path through. But I have no idea if that would work in a corporate setting ie. would I lose half my workforce if I did that ?! Mind you, they may already have these. [/pretentious aside]

We used to have a saying as young hospital resident doctors : when you arrive at the scene of a cardiac arrest the first pulse to take is your own ! :-) :-)

It is very material that the Dragon escaped intact and functional after an explosion just beneath it. If not for inactivation of software ( prior expectation ) it might be here today, which is a shame as follow through on that would have been an amazing start-to-end validation of design. For any crew, surviving the vicinity of such an event is the hardest bit.

Cheers, Mike.

I have made this letter longer than usual because I lack the time to make it shorter ...

... and my other CPU is a Ryzen 5950X :-) Blaise Pascal

Mike Hewson
Mike Hewson
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There is a new clip from

There is a new clip from SpaceX showing off manned Dragon interior features. Stylish or what ? How ultra cool would it be to pilot a craft with this set of options :

BTW : the one of the far right ( out of focus ) is "Initiate Thorne Transit" ... :-)

Cheers, Mike.

I have made this letter longer than usual because I lack the time to make it shorter ...

... and my other CPU is a Ryzen 5950X :-) Blaise Pascal

Anonymous

RE: There is a new clip

Quote:

There is a new clip from SpaceX showing off manned Dragon interior features. Stylish or what ? How ultra cool would it be to pilot a craft with this set of options :

BTW : the one of the far right ( out of focus ) is "Initiate Thorne Transit" ... :-)

Cheers, Mike.

What!!! No double expresso. Looks too much like the set of Star Trek. I think I would prefer to fly on the Nostromo. It ain't purty but gets the job done.

David S
David S
Joined: 6 Dec 05
Posts: 2473
Credit: 22936222
RAC: 0

RE: There is a new clip

Quote:

There is a new clip from SpaceX showing off manned Dragon interior features. Stylish or what ? How ultra cool would it be to pilot a craft with this set of options :

BTW : the one of the far right ( out of focus ) is "Initiate Thorne Transit" ... :-)

Cheers, Mike.


I hope those commands require confirmation when you press them.

David

Miserable old git
Patiently waiting for the asteroid with my name on it.

mikey
mikey
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RE: RE: There is a new

Quote:
Quote:

There is a new clip from SpaceX showing off manned Dragon interior features. Stylish or what ? How ultra cool would it be to pilot a craft with this set of options :

BTW : the one of the far right ( out of focus ) is "Initiate Thorne Transit" ... :-)

Cheers, Mike.

I hope those commands require confirmation when you press them.

Yeah fumble fingers could be REAL bad couldn't it!!

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