I know this story is getting old. And, frankly, this isn't as deep of a dive into carbon fiber as I would have liked to have seen.
The part that truly surprised me in this article was learning that OceanGate's Founder and CEO, Stockton Rush had a degree in Aerospace Engineering from Princeton.
I cannot understand how someone with what should be proper engineering training would ever consider using epoxy for a submarine pressure hull.
I say epoxy because that is nearly the only thing resisting pressure in a submerged CF hull. Also, the half-spheres at the ends caused axial loading, which was probably nearly 100% opposed by epoxy as well.
Errors and accidents are part of every day engineering. I don't classify this as either one of those. This falls under the category of sheer stupidity.
Sorry to be so harsh. I cannot imagine how anyone with a reasonable understanding of materials science would not laugh at a proposal to use CF as a pressure hull. This is a proposal to accept assured catastrophic failure (and death).
Here's another article from the same site on another design that never "flew":
This article reveals that someone named Brian Spencer with, as they put it "his multiple engineering degrees, including a PhD from the University of Nebraska in engineering mechanics and publications galore".
Spencer was contracted to design the hull for the OceanGate sub. He was, again, according to the article:
"was given 6 weeks and told he had to meet a few design constraints—a length of 2.54 m, 1.676 m outside diameter, service pressure of 6,600 psi (roughly the pressure at 4,000 meters), and a safety factor of 2.25"
I am even more surprised about this. So, at least two real engineers, one Aerospace and the other a multi-degreed-PhD, actually moved forward with a bullshit CF pressure hull design.
Again, anyone who understands CF know this 6,600 PSI and safety factor of 2.25 is a bullshit rating. It could go down to 500 PSI and zero safety factor after just one dive to, comparatively speaking, a moderate depth. And you would never know that happened. CF does not work under compressive loading because the only thing holding it together is epoxy.
To make things even worse, from the article:
"Spencer Composites’ first design of the Titan used carbon fiber for all the structure, the hemispheric endcaps as well as the cylindrical body"
"The Applied Physics Laboratory at the University of Washington <snip> ran pressure tests on a scale model of the Titan <snip> the carbon fiber domes failed"
OK, well, these two morons with multiple degrees and even one PhD between them cost a group of people their lives. And this was 100% unnecessary. Not a nice thing to say at all, well, at least one of them paid with his life. Not sure what's happening with the other guy.
These are the kinds of engineering failures I don't like to see. Unnecessary and just plain stupid. This is also why credentials stopped impressing me a very long time ago, decades ago.
I have worked with people from all walks of life. From amazing engineers working at places like Lockheed Skunkworks and SpaceX to guys without university degrees that put most degreed engineers to shame due to their drive, dedication and deep understanding of what they chose to focus on.
The only common denominator in all cases seems to be how committed a person might be to learning, understanding and acquiring no-bullshit experience. Credentials do not provide or guarantee any of that. They can be a starting point, and a very good one at that, yet, they are nowhere close to being the entire package.
>This article reveals that someone named Brian Spencer with, as they put it "his multiple engineering degrees, including a PhD from the University of Nebraska in engineering mechanics and publications galore".
which is specialized in (beside designing) manufacturing every kind of composite material products and hold a number of Patents, including a few related to "pressure vessels".
At least on paper it seems like Spencer and SCC composites are qualified, so - even if they were evidently wrong - they know something about composites that you (and myself) don't know.
In my (very little and tangential) experience with composites, besides the relatively poor resistance to compression that you highlighted[1], I would mention the difficulties in manufacturing that can lead to a product that has poorer resistance than expected and in checking its structural integrity/resistance.
[1] but that not necessarily has been the root reason of the failure, possibly the structural calculations were fine but presurization/depressurization cycles were not taken properly into account or the actual hull had not detected structural defects
"There is a principle which is a bar against all information, which is proof against all arguments and which cannot fail to keep a man in everlasting ignorance--that principle is contempt prior to investigation."
-- Daniel J. Shea, Jr. (1985)
From the Preface of The New Plague: Organizations in Complexity by W.L. Livingston
There is a principle which is a bar against all information, which cannot fail to keep a man in everlasting ignorance — that principle is contempt prior to investigation.
Sorry, you're right. In the paragraph preceding the quote, the last sentence is "Finally, we are reminded of Herbert Spencer's dictum:" (emphasis mine).
The part that truly surprised me in this article was learning that OceanGate's Founder and CEO, Stockton Rush had a degree in Aerospace Engineering from Princeton.
I cannot understand how someone with what should be proper engineering training would ever consider using epoxy for a submarine pressure hull.
I say epoxy because that is nearly the only thing resisting pressure in a submerged CF hull. Also, the half-spheres at the ends caused axial loading, which was probably nearly 100% opposed by epoxy as well.
Errors and accidents are part of every day engineering. I don't classify this as either one of those. This falls under the category of sheer stupidity.
Sorry to be so harsh. I cannot imagine how anyone with a reasonable understanding of materials science would not laugh at a proposal to use CF as a pressure hull. This is a proposal to accept assured catastrophic failure (and death).
Here's another article from the same site on another design that never "flew":
https://www.engineering.com/story/ill-fated-titan-submersibl...
This article reveals that someone named Brian Spencer with, as they put it "his multiple engineering degrees, including a PhD from the University of Nebraska in engineering mechanics and publications galore".
Spencer was contracted to design the hull for the OceanGate sub. He was, again, according to the article:
"was given 6 weeks and told he had to meet a few design constraints—a length of 2.54 m, 1.676 m outside diameter, service pressure of 6,600 psi (roughly the pressure at 4,000 meters), and a safety factor of 2.25"
I am even more surprised about this. So, at least two real engineers, one Aerospace and the other a multi-degreed-PhD, actually moved forward with a bullshit CF pressure hull design.
Again, anyone who understands CF know this 6,600 PSI and safety factor of 2.25 is a bullshit rating. It could go down to 500 PSI and zero safety factor after just one dive to, comparatively speaking, a moderate depth. And you would never know that happened. CF does not work under compressive loading because the only thing holding it together is epoxy.
To make things even worse, from the article:
"Spencer Composites’ first design of the Titan used carbon fiber for all the structure, the hemispheric endcaps as well as the cylindrical body"
"The Applied Physics Laboratory at the University of Washington <snip> ran pressure tests on a scale model of the Titan <snip> the carbon fiber domes failed"
OK, well, these two morons with multiple degrees and even one PhD between them cost a group of people their lives. And this was 100% unnecessary. Not a nice thing to say at all, well, at least one of them paid with his life. Not sure what's happening with the other guy.
These are the kinds of engineering failures I don't like to see. Unnecessary and just plain stupid. This is also why credentials stopped impressing me a very long time ago, decades ago.
I have worked with people from all walks of life. From amazing engineers working at places like Lockheed Skunkworks and SpaceX to guys without university degrees that put most degreed engineers to shame due to their drive, dedication and deep understanding of what they chose to focus on.
The only common denominator in all cases seems to be how committed a person might be to learning, understanding and acquiring no-bullshit experience. Credentials do not provide or guarantee any of that. They can be a starting point, and a very good one at that, yet, they are nowhere close to being the entire package.