Friday, October 12, 2012

Container vessels capacity

In the form that follows the cellular container vessel dimensions are input and her 20 ft TEUS capacity is estimated
This 2nd. edition fixing some errors and adding drawing of Containers in holds

Click to begin calculation



(updated on 21 Feb 2012)



Thursday, August 9, 2012


"La Naval" shipyard of Sestao(Spain) launches the "Joseph Platou"
 "Fall-Pipe" type vessel for Jan de Nul

On August 3, 2012 "La Naval" shipyard, in Sestao (Spain), of the CNN group (Construcciones Navales del Norte =  Northen Shipbuilding) proceeded to launch this vessel for the Belgian shipowner Jan de Nul, a regular customer of this shipyard which has already delivered a twinship, "Simon Stevin", and several suction dredges, including the two largest in the world, in its class, "Cristobal Colón" and "Leiv Eiriksson". About these ships I already included posts  stressing their notability and the "La Naval" capacity to build such a high technology ships and competing worldwide with major shipbuilders .

The shipyard invited me to attend this launching, that I thanked especially in these times of shipbuilding drought , as evidenced by the absence of a keel laying after this launch, as was to be the norm in old good times when shipyards laid the keel of following ship waiting her turn in the queue of orders. I have news, unconfirmed, that "La Naval" will finish the construction of two medium-sized vessels begun in the late Seville shipyard, what will lead to an easing of shipyard situation in the absence of "serious" contracts, matched to its proven category and capacity. I hope that the "tax lease" system  resolves soon, after many months of stand-by, without which the shipyards in this country would have many difficulties to survive.

In this post about the "Simon Stevin", first ship of this series, I summarized the main features of this vessel whose dimensions are

 Overall length (m)     191,50
 Breadth (m)       40,00
 Depth (m)       13,20
 Draught loaded (m)         8,50
 Deadweight (tonnes)     32.500
 Speed (knots)       15,50
  Crew        70
         Propulsion
 Azimuthal propellers  4 x 4.500 Kw
  Retractable propellers  2 x 2.000 Kw
 Electric generators  5 x 3.300 Kw

Delivery of "Joseph Platou" is scheduled for early next year.

I wish I had taken pictures and video of the launching from the other side of the river, but as I saw it from the guests platform visibility was very poor and I include here some photos of the event only as a recollection, nothing to be with quality.



Ship launching seen from the visitors platform


Wednesday, July 4, 2012


Which sails quicker the rowing boat "trainera" or "trainerilla" ?

The great mathematics magazine + Plus Magazine, in its May 2012 issue published an article entitled "Outer space: Canoeing and kayaking", authored by John D. Barrow, which raises the question of whether these boats run more or less when they double the crew, which we do not know in advance because if the propulsive power is doubled so does the displacement and therefore the hydrodynamic resistance.

+ Plus presents simple and reasonable equations to estimate the variation of this resistance and determine from it the necessary power increase, which compares with the increased power provided by the additional rowers. He gets a theoretical conclusion that  a double crew boat increases its speed by 8 to 10%, what matches well with the actual data recorded in kayacs and canoes races. This conclusion appears consistent with the intuitive impression we have that larger similar boats are faster than smaller ones. 

Saturday, March 10, 2012

A new site about Naval Architecture

A new website about Naval Architecture


In the February issue of the Spanish journal Ingeniería Naval (Naval Architecture) they report the creation of a new website entitled "Revista del Sector Marítimo. Ingeniería Naval" (Journal of the Maritime Sector. Naval Architecture), whose stated aims are to "... encourage news update daily and flexibly, enabling readers to easily find news of interest through tags that allow you to select all news related to a topic."


This website is in this URL "Ingeniería Naval"

The journal editorial keeps saying they have tried that the new website be accessible from the largest possible number of devices in addition to PCs, such as tablets, already in operation, and smartphones, which will be soon.

Index of sections of the website is this
  • Home
  • Information
  • Maritime news
  • Maritime energies
  • Magazines
  • Subscription
  • Reports
  • Ships
  • Applications
  • Sitemap
The preceeding items are subdivided, in some cases, into lower levels and in particular, subscribers have access to the full contents of the journal "Ingeniería Naval" (Naval Architecture), on all its numbers since 2004 when the digital version was created, that is also handed over annually on a CD.

The inclusion of RSS allows you to add news to feeds readers and share them on social networks like Facebook and Twitter and to connect to the video channel of Naval Architects at Youtube.

I think that this site is very well presented with large and handy information and although it is currently a complement to "Ingeniería Naval" paper magazine edition, I think, is my opinion, that it will not be long until they retire the latter from the market, because, contrary to the opinion of some friends of mine, I think that although currently books and publications coexist in digital and paper formats, the very next generations will know the latter only in museums.

My congratulations to the AINE President, José Esteban Pérez Garcia and to the Journal Director, Belén García de Pablos, together with all their team, for the creation and promotion of this new publishing media, which I hope will help to reactivate the decayed shipbuilding situation in our country.

Monday, February 27, 2012

First and last aircraft carriers

First and last aircraft carriers

The first one



By chance I found an online article (Ref.1) about the first aircraft carrier in naval history, i.e. the first ship on which an aircraft landed and took off. It was the cruiser Pennsylvania, of the U.S. Navy, and the first landing on its provisional flight deck occurred on January 18, 1911, in San Francisco, California, by a biplane aircraft Curtiss, piloted by Eugene B. Ely , a U.S. professional civil pilot.



Friday, January 20, 2012

Should cruise ships have a double hull ?
Considerations on the Costa Concordia accident

The recent accident involving the cruise ship Costa Concordia on the Italian coast of the Giglio Island is producing the usual questions that arise after any disaster affecting human lives. It is the question of whether the safety of the facility in question is sufficient, be it either a ship, aircraft, train, skyscraper etc. Clearly there is not a complete safety in any order of life, but it is also clear that any current safety level can be improved and the issue is deciding when and where the laws and regulations governing safety are to be changed to get better expectations.


History teaches us that mankind is learning the hard way. When we suffer a great accident is when we consider that perhaps safety provisions are not adequate and should be analyzed in detail and realism to decide whether they should be improved.

Wednesday, January 4, 2012

Cálculo del peso en Rosca

Ship lightweight Calculation

(In cargo ships preliminary design)


Introduction

The calculation of the ship lightweight and her center of gravity is one of the basic tasks to be performed in the ship initial design stage, where it is advisable to be able to perform quick, approximate calculations, allowing to quickly analyze many alternative dimensionings. In this blog I present a form to enter the main dimensions of a cargo ship from which the program computes, approximately, the ship lightweight and center of gravity height broken down in Steel, Equipment and Machinery. Results are limited to ships up to 320 m. length between perpendiculars and aspect ratios should be normal.