Having some experience in both vessel design and construction, I've decided to try a little experiment. Using MacNaughton's Scantlings Rules for Wooden vessel construction, I'm gonna calculate the scantlings for a 450' wooden vessel. (There are other scantling rules, but I am familiar with MacNaughton's having worked in that design office for some time.) It'll take me some time as I have to load the calculations into my iMac and figure out the displacement to get the scantlings number. If I can get the time I may even sit down at my table and draft something out to be able to do the proper hydrostatics and stability calculations. If someone could help me, I need- # of animals/kinds (WTH is a kind anyway?) Amount /weight of food How much time Noah and his sons had for felling/milling the wood and constructing G-D's yacht? My gut feeling is that the Ark is unfeasible. A wooden boat that size, with no way to control it during a tempest that would make the Perfect Storm seem like a summer Sunday sail, would most certainly broach, break apart and be lost with all hands (and paws).
19th century vessel were not often scientificly designed, but relied on the experience of thousands of years of building. The old timers knew oak made the best backbone and framing and, if available, the planking. Metal hulls gained popularity partly due to the lack of available usable timber, but wooden vessels were built through the 19 and 20th centuries. Steel vessels are not immune from destruction at sea. They still break up in storms. More are lost every year than most realize! Scantlngs for wooden vessels were available from LLoyd's and the ABS until recently. They discontinued them due partly to lack of demand. Could you please add a link to the tank testing you mentioned? Granted, the displacement calcs are fairly easy, but the weight calcs are vital to see if the vessel will float on her DWL. If not, then the stability calcs go out the window. Weight of crew, passengers anticipated (critters) food and water, rig, etc., are always calculated as part of decent design. BTW, whose scantlings are you using?
allanroyboy keeps using a single timber analogy for strength, seeming to forget a wooden vessel is a sum of its parts. All members, backbone, deck planking, framing, work together to give the vesswel its strength. What NA sources are you using? John has very good points, allan. Try incorporating all the forces into your "calculations". Your unsteerable box is gonna rise, fall, spin, corkscrew and roll in the storm. All inside her are gonna be poured out as though having spent a year in a cement mixer. I hope to start the calcs this weekend, work permitting.
I find that Arkies can't seem to agree. John Woodmorappe giver a displacement of about 20,000 tons with a 23' draft, yet David Collins says 7240 long tons with a 7.5' draft. www.bibblicalcreation.org.uk/biblical_studies/bcs046.html THAT is a heck of a lot of freeboard! Generally, though, 20,000 ton displacement seems to be the one most of those folks seem to agree on. I have given a quick look at Woodmorappe's bbook on Noah's Ark and on first impression, it seems well written but feels flawed. I am even more suspicious of his qualifications when I find out it is a nom de plume of a creationist highschool science teacher. No agenda there, eh?
Scantlings have been entered, but a true calculated displacement has yet to be calculated. "This rule is bbased on the displacement (total weight) of the vessel in a fully loaded condition. The displacement is expressed as the number of cubic feet of the [vessel's] hull beneath the load water line (LWL)" We will have to assume a Design Water Line (DWL). When my board is creared, I will have to draw out a profile, plan view and 10 sections, actuall only one if we assume a rectangular box shape. From this, I can run my planimeter to calculate the 10 sections needed to use Simpson Rule to figure an accurate displacement. Storing the wood also seems to be a problem. Boat lumber should have about 12% moisture. Green wood is a no-no and too dry wood will absorb a lot of water when the vessel is splashed and could actually spring planks. Saw that happen once. Not a pretty sight. Good point abbout the animals. The more I look into this whole thing, the more I find Arkies waving their hands. Animal infants, carnivors eating plants, saltwater fish surviving massive amounts of fresh water. Suspended animation even? chuckle
Not having seen the T.V. show on the Ark, I cant comment on the tank testing that they did, but I assume it is just like testing done on merchant and naval vessel. That sort of testing is good for testing performance and some stability, but not for strength of the design. For that one would have to construct a fully scaled model, plank on frame, and subject it to various forces to destruction. This is almost never done in tank tests, so testing is done on computers. Do you have any computer modeling data to share with us? None of the Ark sites I have visited give any hard data, just so-and-so reports this and information from an uncited source reports that. The scantlings rule I used can be purchased from MacNaughton Associates at www.macnaughtongroup.com I used the Seine River barge design as the model. These are almost totally rectangular, with a small amount of curve in the bilge and a bit of rounding at the ends.
LOA -450 LWL-450 BWL-75 Draft-23 Freebboard-22 Disp.-22,178.6 long tons (volume, not actual) Plank thickness-13.785 (min. single plank) Plank thickness-10.33875 (ea. Double planked) Frames, double sawn, S&M-22.975 (ea.) Frame spacing-137.85 (min. on centers) Trunnel fasteners dia.- 5.169375 (assuming no metal fasteners) Keel, molded-64.33 (min.) Keel, sided-128.66 (min. at widest point) Stem, sternpost, horn timber, S&M-55.14 Bilge stringer, thickness-13.785 Bilge stringer, width-192.99 Clamp/shelf, S&M-43.193 Floor timbers spacing- as frames Floor timber, sided-22.975 (min) Floor timbers, molded-45.95 (min) Partner knees, sided-22.975 (min) Partner knees arm legth-201.03125 (min.) Weather deck beams-as framing ( as the stresses on the vessel flow to all point, the Decking- as planking deck should be as strong as the hull) Butt blocks- sided as planking. Oak.
If a truly flat bottomed structure is required, my guess would be to have the chine logs sided and molded to 64.33 min. Planking should run longitudinally, not transverse.
All structural members should use keyed hook scarfs at least 12:1 when required. Interior deck clamps as weather deck. Beams and decking as weather decks.
Materials: Structural members- White Oak or wood of similar properties. Longitudinal members-Teak, Honduras mahogany, longleaf yellow pine. Planking- white oak, mahogany, longleaf yellow pine, white cedar, teak. Decking- Teak, longleaf yellow pine. Trunnels- Locust or white oak.
Actually, I think that "gopher wood" was a mistranslation. Careful reading will show not a discription of the wood type, but what Noah must have been telling his sons for a hundred years. GO FER WOOD! Over and over and over and....
Found an interesting site. www.flood-myth.com It is generally accepted by most serious biblical scholars that the flood tale originated during the Babylonian Captivity. This site covers some of the Mesopotamian sources for the story. An N.A told me that any wooden vessel over 200' would need to have diagonals to prevent hull distortion. Old Ironsides was designed with them and kept her shape until the mid-late 20th cent. when they were removed for restoration. They were reinstalled after the ship began to hog. The U.S.S. Consellation was buit without them and hogged severely, allowing her to leak like a seive. Data seems to point to the impossibility of anyone, now or then, building a 450' wooden boat that could survive. (unless magic is invoked). Anyone who has ever worked on wooden structures, marine or otherwise, can look at the scantlings posted and figure out if 5 Bronze Age men could build such a structure.
I read the links on the 400'+ Chinese ships, but they just mentioned legends of the huge trading ships, but no evidence that they existed, except for one "rudder post" discovered by researchers. All the archaeological evidence points to Chinese shipbuilders having technology not beyond the norm. Could the legend of a 400' ship be just that? A legend? The Chinese are as adept at hyperbole as anyone else. "Look how great we were! We once built a ship to dwarf all the ships of the barbarians!" I still see no evidence that a 450' ship was ever built by Bronze Age people. Or could have been.
The scanlings number, cube root of the displacement in cubic feet, is the scantlings number which is entered into the formula. I posted the site you can purchase the rule from. It is not just the keel, but all the longitudinals, as well as the planking, that gives strength. (Crushed deck beams will compromise the entire structure.) The deck specs were included. I was using the barge as a hull form, not as a total model. If Bible litteralist would take a fraction of the multimillion dollar ministries funding and fund a replica, then we'd know, wouldn't we? ICR and AiG, as well as people like Swaggert, Falwell, et al, could come up with, oh, let's say 25 mil, to get it started and all the labor could be 4-8 volunteers. I'm sure volunteers could be found for such a project. (Large ship replicas are currently being built all over the world. See the last 3 issues of WoodenBoat mag)Build the thing, how ever you like, fill it full of animals and float it in the North Atlantic for just the winter months, crewed by 8 people. One rule, though. No modern conveniences, pelletized feed, MRE's, etc. Could be fun, eh? Sorry if the post is not quite organized. My 33 month old son wants to help me on the 'puter.
Allen, Have you ever taken a boatbuilding course. Have you ever been a part of a crew building any type of wooden vessel? Have you ever actually built anthing in wood by your own hands? Or are you just parroting information as it suits your needs? Do you even truely understand what you're regurgitating? For almost 20 years I've sailed, built and worked on design teams for vessels of many sizes, wood, glass and steel.(not counting my time on 378' CG cutters.) I'm not sure where you are coming from so I thought I'd let you know where I'm coming from. John has many points you are ignoring. Try reading and understanding what people who know are trying to tell you. Bonobo out.
I did a little investigating on Shearer and Assoc., the people that did the stability study for Mr. Silver's Ark specs. Please note that they steel design barges, not ocean-going craft. Also, Mr. Silver put in a transparent overhead and transverse bulkheads. He seems to have also included some modern stuff in a bronze age boat. Shearer did the calcs assuming the Ark was a box and no provisions were made for surviving heavy weather. No moon pool or great honking side hatch. Also, the size and numbers of the animals is not too clear. Silver supplied the figures. Almost all builders, shipwrights and designers I've talked with all smile and shake their heads when I bring up the ark.Reunite Gondwana!