# Ships and seaworthiness **URL:** \ **Category:** Factual Questions\ **Created:** [June 28, 2013, 6:18pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146 "2013-06-28T18:18:02Z")\ **Posts on this page:** 18\ **Page:** 2
**Author:** ![Philliam](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/philliam/32/3011_2.png) [@Philliam](https://boards.straightdope.com/u/Philliam)\ **Post date:** [June 29, 2013, 7:10pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/21 "2013-06-29T19:10:00Z")
I take it you were a ‘tower hand’. Those look like winch controls as I remember them from the pipelay/dredge barges I worked on. ---
**Author:** ![Mr.Slant](https://avatars.discourse-cdn.com/v4/letter/m/c57346/32.png) [@Mr.Slant](https://boards.straightdope.com/u/Mr.Slant)\ **Post date:** [June 30, 2013, 2:43am UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/22 "2013-06-30T02:43:50Z")
> [@pullin](#): > > It depends on how you define “ship” > SNIP Might I trouble you for the name of this mechanical monstrosity? ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [June 30, 2013, 6:22am UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/23 "2013-06-30T06:22:13Z")
> [@Mr.Slant](#): > > Might I trouble you for the name of this mechanical monstrosity? I found it was the Semac 1 . He took the distance picture from the web pages he google’d up. ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [June 30, 2013, 3:46pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/24 "2013-06-30T15:46:15Z")
> [@pullin](#): > > … yours truly relaxing in the foreground. I watched quite a few enormous storms from there. Cool. Do they let you drive? 🙂 ---
**Author:** ![Lust4Life](https://avatars.discourse-cdn.com/v4/letter/l/ecc23a/32.png) [@Lust4Life](https://boards.straightdope.com/u/Lust4Life)\ **Post date:** [June 30, 2013, 6:44pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/25 "2013-06-30T18:44:14Z")
Years ago I was on a Royal Naval County class ship, that went through a hurricane unscathed. The QE2 went through the edges of the same hurricane (I think that it was Louis but I might be wrong, we’re going back a bit) but it got knocked about a bit. ---
**Author:** ![Mr.Slant](https://avatars.discourse-cdn.com/v4/letter/m/c57346/32.png) [@Mr.Slant](https://boards.straightdope.com/u/Mr.Slant)\ **Post date:** [June 30, 2013, 6:50pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/26 "2013-06-30T18:50:43Z")
Bump ride at all? ---
**Author:** ![Lust4Life](https://avatars.discourse-cdn.com/v4/letter/l/ecc23a/32.png) [@Lust4Life](https://boards.straightdope.com/u/Lust4Life)\ **Post date:** [July 1, 2013, 12:03am UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/27 "2013-07-01T00:03:06Z")
The ship was literally thrown all over the place, there was a hell of a lot of seasickness, and minor injuries from being thrown against bulkheads, and I got attacked by a bottle of squash when I opened my locker. But I’m glad that I had the experience. ---
**Author:** ![pullin](https://avatars.discourse-cdn.com/v4/letter/p/c57346/32.png) [@pullin](https://boards.straightdope.com/u/pullin)\ **Post date:** [July 1, 2013, 10:15am UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/28 "2013-07-01T10:15:06Z")
Sorry, been on the road for awhile… \*\*Philiam \*\*is correct, I was a tower hand (among other things… rigger, crane operator, etc.) I was responsible for the 6 forward winches. For those unfamiliar, these were huge. If I remember right, they had 10K feet of 3 inch (diameter) cable, and each had around 1400 HP in the drive motors. The CC cameras were for use to be certain everything was winding on and off neatly. **Mr Slant, Isilder** is correct, that’s the SEMAC 1. I worked on it when it was in the North Sea. **carnivorousplant** , yes they did let me “drive”. That was my job (if dragging yourself along with a bunch of anchors can be called driving). We moved at the breakneck pace of 40 feet every 5 minutes (less than a tenth of a mile per hour, if my math is correct). Old hands tell me it’s converted to DP thrusters and GPS now. ---
**Author:** ![Alessan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/alessan/32/465_2.png) [@Alessan](https://boards.straightdope.com/u/Alessan)\ **Post date:** [July 1, 2013, 11:18am UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/29 "2013-07-01T11:18:57Z")
As an aside, tsunamis aren’t really that dangerous to ships at sea - water goes up, water goes down, end of story. It’s only when they interact with land that things get messy. ---
**Author:** ![Machine\_Elf](https://avatars.discourse-cdn.com/v4/letter/m/82dd89/32.png) [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)\ **Post date:** [July 1, 2013, 11:18am UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/30 "2013-07-01T11:18:58Z")
Watch a few episodes of Deadliest Catch, and you’ll see that during opilio crab season on the Bering Sea, icing is a serious problem: if enough of it accumulates, the boat becomes top-heavy and capsizes. On a crab boat, the deck crew can reach most areas and pound the ice off with hammers. Although massive size affords cruise ships and aircraft carriers some measure of stability in reallly rough seas, I suspect icing would be problematic for them, precisely because there are large areas of the ship that can’t be easily reached by the crew. ---
**Author:** ![Princhester](https://avatars.discourse-cdn.com/v4/letter/p/3e96dc/32.png) [@Princhester](https://boards.straightdope.com/u/Princhester)\ **Post date:** [July 1, 2013, 12:34pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/31 "2013-07-01T12:34:23Z")
> [@Machine\_Elf](#): > > Watch a few episodes of Deadliest Catch, and you’ll see that during opilio crab season on the Bering Sea, icing is a serious problem: if enough of it accumulates, the boat becomes top-heavy and capsizes. On a crab boat, the deck crew can reach most areas and pound the ice off with hammers. Although massive size affords cruise ships and aircraft carriers some measure of stability in reallly rough seas, I suspect icing would be problematic for them, precisely because there are large areas of the ship that can’t be easily reached by the crew. Not really. Icing occurs where spray gets on deck. For a large vessel, the area of the vessel receiving spray is too small compared to the overall vessel to matter. Anyone mentioning cruise ships in this thread needs to give themselves a slap upside the head. Cruise ships have high windage, glass everywhere, often a bridge forward standing ready to get caved in, and are full of breakable shit. Cruise ships are well known, and every time a thread about big strong ships come up Dopers start bringing up cruise ships. With the exception of the very largest, cruise ships are generally modestly sized compared to truly large ships like big bulkers and tankers. Further, the important thing for seakeeping is _displacement_ ie the actual weight of the ship. Only about the top twenty or so cruise ships displace more than about 65,000 tonnes. That’s about equivalent to a panamax bulker. Panamax bulkers are midrange bulkers, and are small by the standard of tankers. The answer to the OP can be narrowed down to: 1/ very large tankers and bulkers (VLCC’s, ULCC’s, capesizes) 2/ very large naval vessels. I don’t know how this competition plays out. Large tankers in particular are very strong, have low freeboard and deep draft which means they are like an iceberg ie wind just goes over the top, they are absolutely massive, and they have the bridge well aft. They will come through essentially anything, given searoom and no breakdowns. Big bulkers are similar but not as large and they have hatches, which can be a weak point (see _Derbyshire_). In comparison, naval vessels have higher windage and with the exception of the very largest of them, are far, far lighter displacement. Only the very largest naval ships displace in the 80-100,000 tonne range. By comparison, a VLCC could be four times that (and a ULCC six times). However, naval vessels have very large crews, and often more than one engine and propellor. On balance, I’d go with the navy. Large commercial vessels almost never just sink in storms these days: they mostly become casualties in storms due to loss of steering or propulsion. When something goes wrong with these they haven’t much redundancy, or a large crew to effect emergency repairs. ---
**Author:** ![Princhester](https://avatars.discourse-cdn.com/v4/letter/p/3e96dc/32.png) [@Princhester](https://boards.straightdope.com/u/Princhester)\ **Post date:** [July 1, 2013, 12:38pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/32 "2013-07-01T12:38:54Z")
Can I add that anyone disputing the figures should be sure they understand the difference between gross tonnage, net tonnage, deadweight and displacement? Most times this subject comes up there is someone who posts without understanding the differences. ---
**Author:** ![nicky](https://avatars.discourse-cdn.com/v4/letter/n/f0a364/32.png) [@nicky](https://boards.straightdope.com/u/nicky)\ **Post date:** [July 1, 2013, 1:07pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/33 "2013-07-01T13:07:13Z")
Bigger isnt better - those big ships will be under massive strain from hogging/sagging. If the MOL comfort can split in two… ---
**Author:** ![puddleglum](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/puddleglum/32/137_2.png) [@puddleglum](https://boards.straightdope.com/u/puddleglum)\ **Post date:** [July 1, 2013, 4:27pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/34 "2013-07-01T16:27:26Z")
The coast guard has self righting boats that it uses to do search and rescue in very heavy surf condition. Even if they get knocked over they can flip themselves back in three seconds or less. ---
**Author:** ![mlees](https://avatars.discourse-cdn.com/v4/letter/m/ba8739/32.png) [@mlees](https://boards.straightdope.com/u/mlees)\ **Post date:** [July 1, 2013, 4:38pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/35 "2013-07-01T16:38:21Z")
> [@carnivorousplant](#): > > Some survived the Bikini Atoll blast, did they not? No ---
**Author:** ![MostlyClueless](https://avatars.discourse-cdn.com/v4/letter/m/ba9def/32.png) [@MostlyClueless](https://boards.straightdope.com/u/MostlyClueless)\ **Post date:** [July 1, 2013, 5:50pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/36 "2013-07-01T17:50:51Z")
The Dutch KNRM (Royal Dutch Rescue Whatever) has self-righting ships. One of them is demonstrated here: Their [website](http://www.knrm.nl/reddingboten/15-en-19-meter/anna-margaretha/) (sadly in Dutch) mentions that one of these ships was toppled over \*thrice\* in a storm \*with one of the doors still open\* and it still made it out all right. ---
**Author:** ![Princhester](https://avatars.discourse-cdn.com/v4/letter/p/3e96dc/32.png) [@Princhester](https://boards.straightdope.com/u/Princhester)\ **Post date:** [July 1, 2013, 10:36pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/37 "2013-07-01T22:36:26Z")
> [@nicky](#): > > Bigger isnt better - those big ships will be under massive strain from hogging/sagging. If the MOL comfort can split in two… There’s something in what you say, but the simple fact is, mostly they don’t. The MOL Comfort had a design defect. That doesn’t mean all big ships do. The simple fact is that commercial ships ply their trade, day in day out, in all weather, entirely unheard of because they do so with such effectiveness. Small rescue craft are all very great and no doubt could “survive” anything, in a sense. But the OP asks about what could come through the worst of storms. A small, capsizable rescue craft might come through a three day storm. If over that period it has flipped a few dozen times what shape is its crew going to be in? Seas that would flip a small rescue craft are only going to cause the master of a ULCC to have to worry about his coffee cup sliding when he puts it down. ---
**Author:** ![Tassvarg](https://avatars.discourse-cdn.com/v4/letter/t/dc4da7/32.png) [@Tassvarg](https://boards.straightdope.com/u/Tassvarg)\ **Post date:** [July 2, 2013, 10:12pm UTC](https://boards.straightdope.com/t/ships-and-seaworthiness/662146/38 "2013-07-02T22:12:49Z")
Seaworthyness is depending on a system including hullform, displacement, propulsion, superstructure, durability and also like princester said, the shape of the crew. The frequency and rate of movement and acceleration are very important for the wellbeing of the people aboard. The crew has to be functional to pilot the ship safely and the ship itself has to stay together, which is a function of hull, displ… Oh, did I say that already? This remarkable [contraption](http://www.ship-technology.com/projects/flip-ship/) is one of the most extreme. A lot of depth, a lot of displacement, and very small surface area, probably one of the calmest places to ride out a hurricane. However it doesn’t have a propulsion of its own. [Previous page](https://boards.straightdope.com/t/ships-and-seaworthiness/662146.md?page=1)