the grey ship

[Exatem]

the point arises from another discussion and more precisely from this post.http://www.cad3d.it/forum1/showpost.php?p=260515&postcount=55I will now try to explain what steps are to arrive at the construction of a new military unit.

Before leaving with the project of a war unit, let's see what it can serve.
a military ship is a carrier equipped with everything necessary for the use of the weapons it carries. so that the project is correctly set, it is necessary to have clearly what the purpose of the means is to be realized.
It must be clear that we are talking about a means destined to an armed force whose task is to prepare men and means to combat. All the rest, such as peace, humanitarian, rescue, civil protection missions, are not the primary tasks for which it is conceived.
the project will therefore be conditioned by the primary tasks of a warship.

We therefore introduce the concept of "sea power" and try to explain what is meant by this term. In essence it is the ability of a nation to use the sea for its own purposes and for its interests maintaining “control”.
control of the sea is in fact essential when the economic strength of a country is based on activities connected to it. In order to exercise the maritime power, a “force” is required to defend its interests and the economic prosperity that it derives from them. of course the consistency of this “force” and directly proportional to the deterrence value that you want to achieve. This value is also called “projection” and represents the so-called dissuasion strategy with which the use of force is avoided in case of disputes and disputes.

even if the claim I am about to make will appear questionable, this projection of power is that which reduces the risk of wars between competing countries.

the present picture is characterized by serious episodes of regional instability that are moderated by politics and diplomacy. when they have also exhausted their functions, the use of war is practically inevitable unless the presence of a “deterrent force”. but so that this deterrent is effective, it is necessary to have a sufficiently credible force. This force in our example is represented by the military navy.
but it's not just that.
a military navy must also fulfil other tasks and these are: surveillance of maritime interests, competition in defence of the nation, participation in international commitments. to these tasks, there are others who have taken considerable importance these days: the control of illegal immigration, the protection of activities on the sea (lotta to piracy), the control of illegal trafficking.
all these tasks contribute to determining the size and structure of the marina which is not limited to the fleet alone, but requires a logistics and staff to support the systems. This complex to be maintained in efficiency requires considerable financial resources whose requirements affect what is defined as “cost relief”.

Since we started talking about money, we get into the cost of a military unit. from cost analysis, it is immediately noted that the “components” affect them very significantly. in a modern frigate, for example, the combat system affects up to 40% of the final cost. This is because there is a concentrate of cutting-edge technologies but that have a short life cycle “ageing” in fact, within a few years determining an unknown phenomenon to those who are outside the environment called “common obsolescence”.
I try to clarify with an example.
Suppose we have to make a class of eight frigates. at the time of the definition of the commission they will have boarded the system of weapon that represents the best of that moment. but it will come the day when they are obsolete and will be at the same time. therefore they must be replaced by other units of new design, with new costs certainly greater than the previous ones, it is in fact unthinkable to replace an old ship with a new at equal costs.

After this premise, we see the steps through which we reach the definition of a new war unit.

six phases are identified:
general planning; logistic-operative planning; executive, technical, technical and administrative; operating.

the initial phase is that of the “general planning”, of the competence of the major state, in which the necessity and the possibility to realize the enterprise is defined. It is at this time that the type of unit is identified (caccia, frigate, corvetta, auxiliary units ...) that will have to meet the needs deriving from the "long-term programmatic plan". this is one of the major criticisms because since a naval program is thought, financed, to its realization, it takes on average 10 years. once during which international political situations can change even radically by further dilating these times to even less need.

the second phase is that of the “planning logistic-operative” in which the operating requirements are defined, i.e. the tasks to which the new ship will have to fulfil. It is here that the “fighting system” is defined: the type of armament, the shooting management systems, the missile guide, the active and passive sensors, the control and control systems. other characteristics that are defined at this stage are the so-called “platform” i.e. the maximum and operational speed, autonomy, other possible characteristics and, the “arming table” technical term to define the crew.
a series of past feasibility pre-analysis which, the project assumes the definition of “general operational specifications”.

Now we finally have something concrete to work on. We can therefore begin to process the “maximum project” during which the ship assumes, on paper, the aspect that will distinguish it for its operating life. in this phase the designer must be able to reach the best compromise between systems and platform without forgetting the logistic and marine accommodation, the static and dynamic stability, the seal to the sea, the anti-falla and fire protections. At the same time, it is necessary to ensure the widest “view” to the weapon systems and sensors while maintaining electromagnetic compatibility and reducing radar, acoustic and infrared signals. (follows...) )

 

[Exatem]

(...cont'd)

we arrived at the “technical moment” in which the ship is perfectly identified in its “geometries”.
length and width are known as displacement. each service has its location and the “volume” of which need. from this moment it is no longer possible to introduce or reposition these locations unless you have to review the project by returning to the previous step (we are inside the famous “project vacuum” and as in the game of the goose, each false step turns back one or more boxes).
but we are particularly good and we have also passed this phase.
now the technical specifications must become “contracts” for the supply of apparatuses and “industrial acts” for the construction of the hull (the assignment to the yard).

the “technical-administrative moment” is the moment of truth.
If the project is realistic and feasible, it can be translated into a “Detail Project”.
the realization of the project begins and the ship takes shape on the port of call.
in this phase the technical offices verify the exact correspondence between the specifications and works realized. After construction, the hull passes to the stage of preparation during which tests are also carried out.
if everything is in order, you pass to the “operational moment” in which the suitability of the new unit is certified to fulfill the tasks foreseen.

these listed until now are the steps to arrive from an initial “idea” to the ship evaluated in its environment, the sea. but to reach the conclusion of the path is fundamental the task of the designer who, at the technical moment, transforms the “operational indications” into a “project finalized. ”
This phase, which I mentioned before, deserves a deepening. fundamental is the analysis of the project theme. in it must be considered the weights, dimensions, power absorption of the armament and its ammunition, telecommunications equipment and electronic warfare. the maximum speed reached and the maximum continuous speed with the relative autonomy, the requirements of dwelling for the crew, the antishock norms, the silence, the stability to integral ship and in case of failure. at this point you can finally take in hand the pencil and sketch a first evaluation of the length and width considering the possibilities of installation of the various components. is still a maximum assessment in which the minimum requirements of the various premises and systems must be met.
here we realize how much the combat system and the motor apparatus condition the dimensions of the ship. and if the first can be considered a “constant” (for each system are well known weights and volumes), the motor apparatus is instead a “variable” because different solutions can be studied to obtain the same result. there are then other values that can be defined constant in the variability of the chosen solutions.
For example, if we have to install a cannon, we must consider that for the food chamber and for the loading system it will not be possible to descend below a distance from the extreme prora, less than 16-22 meters. this distance is dictated by the starvation of the prora and the need to leave the space necessary to the marine accommodation (although it is preferable to avoid the instellation to have a greater field of shooting of the weapon).
for each cannon (or other weapon system) however are known the minimum distance to hold from the perpendicular forward, moreover are indicated the recommended values such as the distance from the walls, the areas of shooting to cover, the distance between similar or different systems.
the central zone of the ship is generally dedicated by the motor apparatus and radar and telecommunications systems which require large antennas that are often placed on large trees.
we see how the engine system is dimensional. This is an iterative process because in order to achieve a certain maximum speed you need a certain power that is dependent on the size and the displacement but that in turn, depend on the power and type of am, so the local ams and generators are defined by taking for example similar plants already realized. the axis lines generally have inclinations contained between 1.3° and 3° and prefer solutions to two propellers as they guarantee excellent manoeuvrability and security in war since independent of each other. always for this reason it is recommended to separate power generation plants.

If a helicopter component is planned between the weapon systems, it is necessary to consider in addition to the number and type of helicopters, all the required rooms. so the stern will be “transom” and will have to present a length of about 25 meters free from obstacles. In addition to this, a hangar must be provided for aircraft shelter, a fuel supply system and fuel tanks. vessels and means of rescue and service complete the equipment.

Now the length of the ship so determined begins to be sufficiently realistic and can allow to determine the height of construction and the width of the hull. to do this, you use predefined relationships. for example for a frigate the ratio between length l and height d is between 12 and 13, while the ratio between l and width b is between 8 and 9. We finally begin to have reliable data on which to work and it is possible to assess with greater precision the dislocation. the displacement must be as little as possible able to satisfy the request finding the right compromise in the volumes.
the project goes on with the choice of the hull that can be made using the systematic series, or looking for already experienced hulls, honing them to the needs.
choose the hull, you run the “building plan”, the first and most important of the designs of the new unit (and one of my favorite works). the next step is the choice of the engine system that will have to provide the required performance with less weight and bulk. on small medium ships, diesel engines are used while gas turbines are used in combination with diesel engines. steam has practically been abandoned due to the encumbrances and the large number of workers you need.
Now you have to define the compartmentalization whose purpose is to contain the damage in case of failure. you get by predisposing a number of stagnant wallpapers whose number must comply with the mm standards that provide that a unit should be able to float and navigate with more adjacent compartments. range from a minimum of 2-3 compartments adjacent to larger quantities depending on the role covered.
we are now preparing the “general plans”. you start positioning the elements seen so far, weapon systems, motor apparatus, antennas; then we switch to the definition of all the other accommodations at the end of which we define the load exponent and it occurs thirsty and stability of the ship is integral, and damaged.

We're at the final jokes. the “sea keeping” is the ability of the ship to operate without restrictions in particular sea conditions. to do this you rely on theoretical methods, calculation codes and simulation in naval tank. it is necessary in practice to improve the seal to the sea by minimizing roll and sanding by reducing the consequent accelerations that are negative both for equipment and for systems (we do not forget that a warship must be as far as possible, a stable shooting platform).
the factors that influence the sea estate are: the length, the free edge, the prora bulb, the same forms of the prora and the active and passive systems of stabilization. to this it must be added that the physical conditions of the crew, influence the operational capacities of the ship for which it is necessary to reduce the disturbances caused by a ship "balla" and the damages that can be caused by "slamming" and "wetness" in addition to the undesirable outbursts of the helicopters (propeller optimize). all these events are evaluated and values are established that should not be exceeded. a modern warship is a set of systems that must be made operate by a crew.
but the movements of the ship can have very negative effects on men, structures, apparatuses. They can even prevent certain functions of the ship, such as flight operations. in practice the same operation of the ship can be compromised. not being able to completely eliminate these effects, our task is to reduce them to acceptable values so as to ensure the operativity of unity in the broadest condimeteo spectrum.

we have taken everything from the project spiral.
several times we have been forced to review, rethink, start again, before seeing a new grey ship carrying our flag.
I have not deliberately entered the detail of the solutions adopted as it would need a lot of time and space. In fact, you could choose on which engine apparatus to adopt, on which system to take for the treatment of gray and black waters, how to desalinize water or which missile system to choose.

In short, we showed only the tip of an iceberg but much more is hidden under the “surface”.

 

[PaoloColombani]

In short, we showed only the tip of an iceberg but much more is hidden under the “surface”.

and of grace, otherwise you should have written a book, but the books are just that they pay and so we here enjoy this beautiful exposure in general terms on the project management of your units.
are many curiosities, but to begin with, speaking of active stabilizers, are the gyroscopic stabilizers still in use?

 

[Exatem]

and of grace, otherwise you should have written a book, but the books are just that they pay and so we here enjoy this beautiful exposure in general terms on the project management of your units.
are many curiosities, but to begin with, speaking of active stabilizers, are the gyroscopic stabilizers still in use?

As my usual I make a premise for those who read and maybe don't know what we're talking about.

stabilization plants are used to reduce the ship's roll in navigation. the most widespread system is the active fin stabilization system, both fixed and retractable.
In addition to ensuring a drastic reduction in the roll for the well-being of the crew, they allow to increase the accuracy of the combat system. fincantieri for example produces three main "families" of fins.
recttratili with a surface from 2 to 21,5m2;
sliding from 3 to 10 m2;
fixed from 1.3 to 18 m2.
during navigation the hull is subjected to oscillations caused by the wave motion, which must be countered by opposing forces. If, for example, the ship goes straight, there will have to be a direct force down on the straight side and a force up on the left side. to do this we exploit the portance generated by the fins that logically will have little effect at low speeds and greater to the increase of the same (on the portanza could write a treaty our president so I stop here!).
all current roll stabilization or beaking systems are based on electronic error control systems which control the stabilizing fins of the ship, reduce the roll motions or beaking.
We will therefore have an electronic control unit consisting of a software for the operation of the system to which the data relating to the angles of roll, sanding, landing and, the vertical accelerations taken from the compass, by inclinometers and, accelerometers.
the compass "knows" the "0" ship (no displacement) but just registers a change of order, commands the stabilizer fin in order to compensate for the drought.
the data in fact, once processed, will allow the maneuvers to be implemented (in most cases hydraulically).
there are also as well known for years gyroscopic systems of remarkable masses that installed on boats also reduce the oscillating motions.
the above systems have all a limit (or two), that is, the correction of the bike happens as soon as the ship starts to tilt, this means that although the efficient control system will always remain a residual error and the dimensions that on a large ship, become really important I know that on ships of dimensions not too exaggerated, are still used but it is not our case.
about gyroscopic systems, the following is the text of an original publication of the 1930s very interesting also for the lexicon used. reading it, try to imagine a voice like the news of the light institute.. ."the readers of marine Italy have certainly not escaped the news, coming from new york to the newspapers of genova and trieste, about a supertransatlantic Italian, that first in the world, will not roll in the wavy sea; will be the floating paradise for those suffering from sea!
the news is very accurate: It is the building of count of savoy, whose hull is growing on the great port of call of the yard san marco of Trieste.
the direction of the lloyd sabaudo has the "colpa" of this great fact, which marks a very important step forward in the navigation of luxury and not luxury passengers; and it is good that in these columns it passes to the posteriors the fact that, as the Italian warship was first among the Europeans to adopt the gyroscopic stabilizer for some of its ships (r.n.pe and r.n.pigafetta), so it is today our merchant navy to give the world the first great steamship from stabilized passengers.
honour must be made to the clearance and courage of the executives and technicians of lloyd sabaudo.
It is good that readers know that it is not any device of the genus "ice machine" or "flat lavar macchia", but of three huge "throat", each of the diameter of about 4 meters and 100 tons of weight, oscillating and rolling on two orthogonal axes between them. the complete stabilizer plant of the count of savoy will weigh about 450tonnes.
the invention of this intelligent machine, which keeps the ship quietly at sea, is due to the ingenuity doctor elmer sperry, who died last year in America, where he was officially recognized the best mechanical engineer of the United States. he died a few days before the direction of the sabuado decided to adopt his stabilizer for the great transatlantic under construction, and to a friend of his, who visited him before his death, said: "I regret to see that men continue to let the ships roll and torment their own structures, when the ships roll only...after they can't do anything else!! but do not despair: the sailors will open their eyes soon!"
Sperry, who loved Italy and who at the same head of the government had the honour to talk about the stabilization of the ships illustrating his saying with a gyroscopic model, would have had one of the greatest satisfactions of his life if he had lived a month more.
a technical-mathematic explanation of "as the miracle of stabilization " does not affect our readers; they will know that it is not a matter of "stop" a ship that rolls and that has purchased a very important inertia. but it is, in the case of the sperry stabilizer, of the formation within the edge of small impulses " pairs " equal and contrary to the successive impulses that the wave gives to the ship.
big way, the successive impulses obtained inside the edge " kill " the successive outboard impulses, so that the ship never begins to roll, i.e. it does not undergo the thrust of the waves, and it overtakes them holding with horizontal bridges and vertical trees.
with the disappearance of the roll there are all the strong beaked due especially to the vertical thrust that a wave imprints under the prora when it prora presents itself with the non-vertical (rollary) law and with non-started forms (shortening).
gyroscopic recordings, which know more than all scientists, tell us that the ship that does not roll catches for two thirds less,save straight course against the sea. the Imperial Japanese Navy already has sperry stabilizers on two cruisers of 12,000 tons for transport of airplanes; Americans have sperry stabilizers on a transport and a hunt; The land on a hunt. there are also 30 stabilized yacts.
Italy therefore passes in the head to everyone regarding this "turn" in the art of sailing and in the shipbuildings.
few Italian engineers have followed in the last 20 years the work of sperry around the "rotating masses", and the archaine force of the "precession" of the gyroscopes; they will be happy today to see a great application of this force of "precession" that sperry has been able to subjugate and command with a small gyroscope-pilot which is equivalent to a long miles pendulum. it "giroscope-pilot" commands to wand the entire stabilizer plant; his sensitivity is superior to the human one, as our eye and thought arrive late on it to judge the end or beginning of a rolled. "Oh, man, right?
so much to understand the size of these plants, I attach some images.

 

[Onda]

I bow to such knowledge, to the remarkable ability to expose it and to make others participate.
You are making me interesting the warships, which I have never considered such, indeed, I have always considered with some antipathy.
your exhibition, full of technical and engineering details, highlights the design adventure of creating such a complex apparatus and therefore captures and fascinates my attention.
thanks to these exhibitions.
wave

 

[Exatem]

I bow to such knowledge, to the remarkable ability to expose it and to make others participate.
You are making me interesting the warships, which I have never considered such, indeed, I have always considered with some antipathy.
your exhibition, full of technical and engineering details, highlights the design adventure of creating such a complex apparatus and therefore captures and fascinates my attention.
thanks to these exhibitions.
wave

that military history is nothing but a succession of brutal, meaningless slaughters and without purpose cannot be discussed.
the word "war" indisputably always arouses strong emotions, both in one sense and in the other.
but if a ship, like a plane, or another means, is seen as an expression of the technology of a given moment. . .
Well, then it can be "smarting."

I remember reading a very special exhibition on the "beauty of battle". According to those who wrote, there exist in the history battles that tear admiration for their "beauty".
clashes in which the number of weapons becomes indifferent and to prevail are intelligence, tactical and strategic acumen, the ability to maneuver and "leadership".
It is perhaps a difficult concept to "digest" especially if we face such "delicate" issues with cautious attitude if not prevented.
but I can assure you it was an extremely interesting writing.
is history; history of humanity that we are all protagonists of.
and it is the same way of facing the story that revolutionizes and distorts what we now consider absolute certainties.
history is a kaleidoscope and if you roote it, you can change your vision.
For example, those we call "barbars", for the Germans are the "volken anderung" (I hope to have written it well) that is "the people on the way". the First American War of Independence, for the British is the first American Civil War.
therefore it is always about questions of "viewpoints", to sit comfortable on the couch and, to browse the pages of a book that I ogno time you read, and as if you read it for the first time and on which no one has yet written the end word.. .
Thank you for your words.

 

[PaoloColombani]

Oh, man, right?
so much to understand the size of these plants, I attach some images.

Beautiful! to be noticed the innervatures and the dimensions of the supports, in the end must bear all the stresses due to the resistance to the roll of an inertial mass like that of a ship! !
Who knows that bearings used then (?). Today on Flightweel storage Magnetic bearings are used with backup bearings that are not in contact until a crash of the first supports takes place. the container is vacuumed, so that the flyer does not even suffer the friction of the air, and reach speed of rotation fearful! probably in the ship's gyroscopic stabilizers don't need such shortcomings, I imagine that having heavy flying on board is not a problem.