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Author
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Topic: About that Boat - Noah's Ark
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Hmmm
Inactive Member
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Re: T o p i c !
Hi; Wow a thread that is actually running... Is this the best place to ask questions about the seaworthiness of a big wooden hull in a big sea? ("About that boat - Noah's Ark" sounds like it should be about that boat called Noah's Ark to me...) Seems the hogging and sagging issue comes up a bit. So what's the verdict? Have we made up our collective minds yet? Cheers
| This message is a reply to: | | | Message 199 by AdminNosy, posted 12-06-2004 4:51 PM | | AdminNosy has not replied |
| Replies to this message: | | | Message 202 by Hmmm, posted 12-07-2004 4:12 PM | | Hmmm has replied |
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Hmmm
Inactive Member
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Message 202 of 296 (165961)
12-07-2004 4:12 PM
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Reply to: Message 201 by Hmmm
12-06-2004 5:09 PM
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Re: T o p i c !
Hmmm No bites. Pity. It appears to me that we should be able to classify the seakeeping, strength and stability of Noah's Ark as either;
- Impossible in a hull built exclusively from wood by any method.
- Impossible using reasonable bronze age technology (spikes perhaps).
- Impossible to make it seakeep based on the dimensions & scale regardless of the materials used.
Any other options? (in the classification of hull performance only)
With the focus specifically on the naval architecture, this stuff is assessable. A yes/no situation. Either it can be done or it can't be done.
But first, what are the options? Hmmm's to all...
| This message is a reply to: | | | Message 201 by Hmmm, posted 12-06-2004 5:09 PM | | Hmmm has replied |
| Replies to this message: | | | Message 203 by Hmmm, posted 12-07-2004 10:16 PM | | Hmmm has not replied |
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Hmmm
Inactive Member
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Message 203 of 296 (166037)
12-07-2004 10:16 PM
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Reply to: Message 202 by Hmmm
12-07-2004 4:12 PM
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Too big or not too big...
Well, there's a study on point (C) showing L300 x B50 x D30 as an OK spec.
Safety Investigation of Noah’s Ark in a Seaway
| Answers in Genesis
Considering 50/30 is a reasonable B/D for a cargo ship, and L/B is proportionally a little shorter than today's vessels - this bit holds water at least. So L/B/D is in the ballpark. Hmmm. Next: Scale...
The cubit is somewhere from 18" to 21", which makes the ark longer than any timber ship I know. (Unless the Chinese can dig up some more bits of 'junk'). After all, we only have a rudder post and an assortment of feet, so we can't be sure they weren't telling tall stories (or long stories). When it comes to building ancient ships the Greeks had it together, but the Ptolemy IV Tessarakonteres (a few hundred BC) was not provably seagoing. Pretty impressive construction though - check out the mortised edge-jointed strakes. Nice way to deal with bending induced shear. (Casson has good info on this)
Missing Link
| Answers in Genesis
So...
Too big or not too big, that is the question.
More Hmmm's
| This message is a reply to: | | | Message 202 by Hmmm, posted 12-07-2004 4:12 PM | | Hmmm has not replied |
| Replies to this message: | | | Message 204 by tsig, posted 12-14-2004 3:29 PM | | Hmmm has not replied |
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Hmmm
Inactive Member
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Message 205 of 296 (168426)
12-15-2004 7:35 AM
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Too Big or not too Big?
Thanks Flying Hawk; Construction logistics doesn't discredit the ark because we have clear evidence of massive workforces and coordinated construction in the ancient Egyptians and Chinese civilizations. It might be used to cast doubt on the story, but it doesn't DISPROVE anything. Back to the A,B & C's.
Is the 150m wooden vessel a structural impossibility? So far this argument has been based on a perceived limit for sailing ships around 1900. But who says these ships define the limit for a wooden hull? They might define the limit for carvel planked hulls perhaps, but this is not the only way to build a vessel. Hmmm.
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Hmmm
Inactive Member
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Too Big or not too Big...
Thanks contracycle;
Re: "Safety of Noah's Ark in a Seaway" (Hong et al)
Safety Investigation of Noah’s Ark in a Seaway
| Answers in Genesis
The rules for steel ships were used for imposed loads and stability, not hull stresses. So this part of the analysis is independent of hull material and structure (assuming the hull is rigid of course). I don't think much of the random sea (confused sea) state either, in terms of it's low probability in steady wind conditions. Perhaps they used this because they considered it the worst case. Or maybe a default case for comparitive seakeeping studies. A ship in regular waves gets as easy ride so long as it doesn't spend much time broaching (beam sea condition - side on to the waves). But this isn't too hard to organize with a steady wind.
(E.g. See the animation on;
Missing Link
| Answers in Genesis
) Hull form: The Bible doesn't give a shape. This complicates matters considerably (in terms of ascertaining the most likely hull form). I wouldn't bother if it wasn't for the suspiciously good L/B/D and not unreasonable scale. Hmmm
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Hmmm
Inactive Member
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Message 211 of 296 (168822)
12-16-2004 5:26 AM
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Reply to: Message 207 by tsig
12-15-2004 1:11 PM
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Re: pension plan
Little red button, where are you...? Oh found it - thanks for the tip. Thanks for reply Flying Hawk; (Witty title too) Is it OK if we stick just to "oversize hull" issues for the moment? - I'd like to see it through. Besides, any YEC could argue about selling land to pay workers, or how they were not necessarily all brain damaged psychopaths since they still got married (Matt 24:38). Although it's a good point, even the apparent ethical dilemma of a drowned workforce is concluded in 1 Pet 3:19. Back to HULL:
Sounds like you are advocating option A.
quote:
The limit for a wooden vessel is defined by the strength of the wood used. The upper limit seems to be about 300m to 350 feet, and that is using iron reinforcements.
The square-cube law will limit the size of any hull (assuming waves are big enough), and a steel hull will always beat a timber hull in the big-ness stakes. But 300-350ft might be an unecessary restriction for wood. THE ERRORS OF CARVEL PLANKING Let's clarify this alleged 300-350ft barrier for a minute. The extra long windjammers were not limited by the "strength of the wood used", but by joint efficiency. Failure in these carvel hulls was related to the induced shear of primary hull loads (bending and torsion), resulting in plank-to-plank shear strains and leakage. This is not the same as the hull being limited by the "strength of the wood used", in which case one would expect to see failures due to extreme fibre stresses. (e.g. tensile/compression damage of the timber). So the hulls failed due to weak joints, not weak wood. If the alleged length barrier was simply a matter of weak wood then we could easily solve this by increasing the thickness. For example, everyday Douglas Fir handles roughly 1/10th of the stress of mild steel. (These are conservative building code stresses taking into account the higher variability of timber, not laboratory figures which are much higher. In pure lab numbers, some timbers are almost half the tensile strength of steel, which is obviously unattainable in real life). So taking 1/10th as a rough guide you would simply end up with a hull wall 10 times as thick as an equivalent steel skin - which is not very thick at all. However, simplistic beam theory methods do not apply to a carvel hull (parallel plank on frame. See definition http://www.emarcon.net/frontoffice/glossary.asp?LEXICON_I...) because these hulls never approached the mechanical properties of wood. The joints failed first. Carvel planking is simply a flawed design. The planks keep out the water but they do little to contribute to the integration of the hull members into a single beam. The result is a "bundle of reeds" effect, where there is very little shear resistance between planks. (Hence the restoration of the USS Constitution never bothered with the inefficiencies of carvel planking. See Andrew Davis, Keith Gallion of Tri-Coastal Marine, Inc.
article at A Cold Molded Shell for USS Constellation) PROBLEMS WITH IRON STRAPS Analysis of various steel reinforcment options for the repair of the (still-water-bending-moment-hogged) Constitution all suffered the same problem - the steel/timber interface. Hence steel reinforcement is not the best way to fix up the mistakes of parallel (bundle of reeds) planking. The best way is an integrated timber hull such as cold moulded planking (diagonal layers) or edge jointing (such as Greek triremes). This explains why modern timber ships such as the 1994 minehunters used diagonal planking. Hence there is every reason a wooden hull built in an integrated plank structure could outperform even the iron strap reinforced carvel planked hull... and break the 300ft barrier in the meantime. Of course, these approaches add considerably to the labor cost - especially the edge-jointed method. Noah would be best off using a cold moulded hull - which means a lot more sawing and a consistent plank thickness. But most of this is already on
The Flood
| Answers in Genesis
quote:
There are threads here at EvC that covers this point in detail.
There's more now. Hmmm.
This message has been edited by Hmmm, 12-16-2004 09:20 AM
| This message is a reply to: | | | Message 207 by tsig, posted 12-15-2004 1:11 PM | | tsig has replied |
| Replies to this message: | | | Message 233 by tsig, posted 12-17-2004 1:44 AM | | Hmmm has replied |
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Hmmm
Inactive Member
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Re: Too Big or not too Big?
Hi Crashfrog;
quote:
You mean, those Egyptian and Chinese civilizations that so inconviniently both pre- and post-date the flood...
It comes down to the historicity of pre 2500BC dating of civilizations. Since modern scholarship has a phobia about going by written records, they seem to think radiometric dating can solve it all. Even the supposedly well-established Egyptian chronologies could be out by centuries according to a recent shakeup regarding Mediterranean C12/C14 imbalance. http://www.informath.org/14C02a.pdf
Funny how they can consider this significant - they must have a pretty weak dating scheme to go by if you can shake it this easily. "Egyptian chronology does not have secure foundations" (Cryer 1995; Rohl 1995; Hagens 1996) as referenced in above paper. But this particular issue (the dating of the earliest civilization with written records etc - i.e. something to DATE by) all fall into the several millenia BC zone (or BCE or the Christophobic). This is suspicious right away, and sounds very much like the post flood Babel dispersion. So the explanation is simply that dates are inflated. There are much worse problems with the 'other' interpretation - the cave man to civilized man scenario. Why does civilization burst on the scene a few millenia BC? Where are all the Neandethal burial remains? Why do world population estimates extrapolate back to Noah so nicely? How come the world didn't fill up years ago?
quote:
...without any mention of the flood whatsoever in their records
What? No mention of a flood? I think you'll be hard pressed to find a civilization that doesn't mention a flood. And some dramatic similarities with the Biblical account too - which is exactly what you would expect if everyone took the story with them after they left Babel.
You have a better explanation for the global distribution of flood legends? I'd like to hear it. There's more than a few hints in the YEC camp here. Hmmm
This message has been edited by Hmmm, 12-16-2004 09:24 AM
| This message is a reply to: | | | Message 209 by crashfrog, posted 12-15-2004 2:07 PM | | crashfrog has replied |
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Hmmm
Inactive Member
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Re: Too Big or not too Big...
Hi again Contracyle;
quote:
loads and stability impinge directly on the hull and cause stress
You misunderstand the point. First you determine wave loads, then you can do stress analysis. The waves don't care what the hull is made of (so long as it is rigid as I said). I stand by my quote. Imposed loads are independent of hull material. It appears you are not clear on the distinction between applied loads and internal stresses. Have a look at this formula for wave bending moment (ABS);
(from
Missing Link
| Answers in Genesis
) Mw = k2 * C1 * L2 * B * Cb / 1000 (hogging)
Where:
C1 = 10.75 - ((300-L) / 100) ^ 3/2 (for 90<= Length <= 300m)
Hogging k2 = 19.37 (for units in tf.m) There is NO material property involved.
Hong obtained estimates for imposed loads first and THEN did structural analysis.
quote:
...to the best of my knowledge, the most efficient wooden hull designs have been flexible rather than rigid.
No problem - you just need some more knowledge. Try reading the previous link to Tricoastal Marine...which says
"There are at least three false ideas about wooden ship structure that, somewhat amazingly, are still current:
Wooden ships need to flex..."
quote:
they appear to have cancelled out wave action by assuming waves come equally from all sides.
Wrong again. A random sea does not assume all the waves are cancelling each other. Even a non Naval Architect should know a bit more about waves - it would be an absurd fluke for all the waves to have just the right amplitude, wavelength, period and phase to cancel each other out. Hong's credentials;
1977 , B.S. Seoul National Univ., Korea ( Naval Architect )
1979 , M.S. Seoul National Univ., Korea ( Naval Architect )
1988 , Ph.D. Univ. of Michigan, USA. ( Applied Mechanics ) BTW This study was paid for by creationists in Korea, but undertaken at the estabished research centre KRISO, of which Hong is a principle researcher, hence he gets the credit (well, first on the list of 9 researchers anyway. Second is S. Na - a professor of Structural Engineering) You might need to lift your game to demolish this paper.
Safety Investigation of Noah’s Ark in a Seaway
| Answers in Genesis
This message has been edited by Hmmm, 12-16-2004 09:00 AM
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Hmmm
Inactive Member
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Re: Too Big or not too Big...
Hi Contracycle;
quote:
There is a pretty smooth progression of naval technology...
(A separate reply since this is a different issue) That's odd - land based constructions in enduring materals like stone isn't a smooth progression at all. "With spectacular suddenness, an architecture sprang up that was suitable for kings and gods...stone monuments that rank with the most impressive of any age" (Ancient Egypt: Lionel Casson, Leonard Krieger, Time Life Books 1966. But when it comes to ships they have a nice "smooth progression." This doesn't make much sense. For example the Egyptians were floating obelisks down the Nile, but several thousand years later the same rock had Renaissance engineers hard pressed to even move.
Casson puts his finger on it in his summary of Ch3 (Ships and Seamanship in the Ancient World)- "Scant as it is, the evidence unmistakably reveals the second millenium BC as a crucial period for Mediterranean maritime history..." Even with the familiar Greek trireme Casson confesses "Very little is known about the shape and construction of the hull". p89 Triremes 500-3232BC. Sound familiar? The problem is ships rot away, and the scant knowledge gets filled in with a nice smooth curve. But the painstaking efforts of underwater archeology are showing that some of these ancient shiprights could teach the much later Europeans a few lessons - like how to integrate your planking for example - to make a ship strong enough to ram another vessel but light enough to be pulled up the beach by the crew (yes, large ones too). Try doing that with any other wooden vessel know to man. Even the shear size claimed by ancient records of Greek ships had been disqualified by the consensus of opinion - until some super-sized bronze ramming bows turned up. So the KNOWN progression is getting increasingly bumpy. The Greek triremes deteriorated (the earlier ones were built better)...the Chinese regressed...ancient shiprights in India had 500ft water locked drydocks and they lost their ship building skills too... "Scant as it is, the evidence unmistakably reveals..."
Wow - what a phrase. Hmmm.
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Hmmm
Inactive Member
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Re: Too Big or not too Big...
Hi Nighttrain; I've looked around and haven't found much about the Hong paper, Greeko-Roman planking, why the windjammers flexed, the effect of diagonal planking, why iron straps are an incomplete solution... So it appears the scoffers have come to their own consensus that the ark is a structural impossibility based on lack of information. Now - if the PRATT list is not just a metaphor but actually has a refutation of the Hong study - let me at it... BTW. I changed color - I run my screen dark so I can forget - sorry. Hmmm.
| This message is a reply to: | | | Message 215 by Nighttrain, posted 12-16-2004 6:52 AM | | Nighttrain has not replied |
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Hmmm
Inactive Member
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Message 220 of 296 (168995)
12-16-2004 3:27 PM
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Reply to: Message 219 by CK
12-16-2004 12:50 PM
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Hi Charles Population estimate... Start with this one
http://www.ldolphin.org/popul.html
which even includes the apparently anti-Noah data in...
U.S. Census Bureau: Page not found
but put some realistic tolerances into the calcs and you don't necessarily exclude a 4500 year history. Dolphn shows how the KNOWN data actually fits the creation model better. But these estimates done without any Biblical contraint (census.gov) do not give evolution friendly results. We are obviously going to hit the beginning pretty recently despite the usual age inflating efforts. The evolutionist has a problem here. Where are all the people if we have been breeding for such a hypothetically long time? Wars and famine? Hmmm
| This message is a reply to: | | | Message 219 by CK, posted 12-16-2004 12:50 PM | | CK has not replied |
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Hmmm
Inactive Member
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Message 222 of 296 (169019)
12-16-2004 4:12 PM
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Reply to: Message 218 by crashfrog
12-16-2004 12:39 PM
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quote:
It's ludicrous to suggest that our chronologies are that errant.
They used to quibble about decades, now it's 500 years. What next?
This message has been edited by Hmmm, 12-16-2004 05:37 PM
| This message is a reply to: | | | Message 218 by crashfrog, posted 12-16-2004 12:39 PM | | crashfrog has replied |
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Hmmm
Inactive Member
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World population growth rate
quote:
And disease. The Black Plague killed a third of Europe's population in the mid-14th century.
I'd hazard a guess we are going off topic here, (About that Boat - Noah's Ark). Might get admin putting their nose in soon. Read the link - it talks about Europe's plague and it's trivial effect on curbing population growth. E.g. "...the awful figures for natural disasters are very quickly made up for by the subsequent rates of increase among the survivors (Langer 1964)"
quote:
Even today the vast majority of human beings live lives beyond access to regular medical care.
Good point, and these are the countries with the booming populations. So recent world population growth cannot be attributed to modern medicine. Yet another contradiction in the evolutionary just-so story.
quote:
...entirely within the expectations of the evolutionary timeframe...reasonable k values.
Not a good fit for 100's of thousands of years at all, and this is with a loaded dice - unjustifiably low population parameters. Far lower than the fit obtained from any KNOWN historically ascertained data points. (Read the Dolphin link) Anyone can plot these curves for and see for themselves;
To fit an evolutionary timescale into this data you have to make out that mankind has been on the edge of extinction for most of history and then suddenly makes a recovery in recent (KNOWN) history. And all this without an excuse either - not medicine, obviously not war and plague, and definitely not famine in fertile countries... Maybe you could add a big catastrophe into your model - say a big flood or something... you know - some sort of global event ...  Hmmm
| This message is a reply to: | | | Message 221 by crashfrog, posted 12-16-2004 3:56 PM | | crashfrog has replied |
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Hmmm
Inactive Member
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For 500 year issue, see previously cited
http://www.informath.org/14C02a.pdf Hmmm
This message has been edited by Hmmm, 12-16-2004 05:28 PM
| This message is a reply to: | | | Message 223 by crashfrog, posted 12-16-2004 4:36 PM | | crashfrog has replied |
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Hmmm
Inactive Member
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Don't be offended Crashfrog, although the Keenan's article is about about radiocarbion problems (a YEC favorite) and tree rings too, it specifically mentions the dating problems of Egyptian chronology. It also provides room for the opposite argument - faulty Egyptian chronology;
"Of course, it might be that there are errors in the archaeo-historical chronologies of the Ancient Near East. All such chronologies ultimately derive from (archaeo-historical synchronisms with) Egypt (James 1991; Knapp 1992). Hence, if there are errors in Ancient Near Eastern chronologies, then their genesis lies in Egyptian chronology. In fact, Egyptian chronology does not have secure foundations (Cryer 1995; Rohl 1995; Hagens 1996)and some workers have argued for revising it. But one could read this paper as giving the impression that archaeo-historical interpretations control Egyptian chronology, and 14C is just a secondary proof (if it matches of course). Not so. Take the central issue of dating the pyramids, and the complaints about lack of secure 14C dates.
"While the multiple old wood effects make it difficult to obtain pinpoint age estimates of pyramids"
Dating the Pyramids - Archaeology Magazine Archive So for "pinpoint" dating of the pyramids, go radiometric? What a clash of logic. Keenan had highlighted how 14C dates were treated as disposable evidence;
"Too, some archaeologists have said that if they attempt to publish 14C dates contradicting archaeo-historical chronologies, their papers are rejected (Nelson et al. 1990). One archaeologist, reviewing the situation for the eastern Mediterranean, concluded blandly: radiocarbon dates are invoked if they support a particular hypothesis and dismissed if they do not (Merrillees 1992)." It's not a pretty picture, this archaeo-historical-radiometric guessing. (And I bet we've gone totally off topic now...here comes Administrator...) Hmmm.
| This message is a reply to: | | | Message 227 by crashfrog, posted 12-16-2004 5:37 PM | | crashfrog has not replied |
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