Types of Combatant Ships of the United States Fleet
The United States Fleet has in its composition the following combatant units: battleships, aircraft carriers, light cruisers, destroyers, light mine layers, submarines. There are other types such as eagle boats, aircraft tenders, and mine sweepers, which, while they are combatant vessels, have special functions, and do not travel with the fleet when it is at sea on a purely offensive mission.
The Battleship—The battleship, or ship of the line, is the backbone of the fighting fleet. The fleet is built up around this type. The other types of ships required for the support of the battleship force are designed on the need for guarding that battleship force from surprise attack and to assist it tactically in action.
The battleship itself is the beautifully balanced fighting unit. Those responsible for originating its characteristics must carefully study the ships of foreign nations against which it may some day be pitted, they must study the tactical and strategical requirements of this type. The first characteristic developed is that of offense—gun power or power to inflict damage. Having fixed this element in her design, the remaining available weight is distributed between protection or power to withstand pounding by an enemy, and propulsion or speed and steaming radius. Before the Washington treaty limited the displacement of capital ships to 35,000 tons, it was customary in order to get protection, speed, and steaming radius, to increase the size of the ship until the requirements of these characteristics were satisfied.
The three elements—gun power, armor protection, and speed—are weighed one against the other by the designers, until the maximum of each which the ship can carry on her allowed displacement is determined. The designers then proceed with the final plans.
It may be noted here that nations build ships with characteristics to meet their particular national needs. This applies to all types of fighting craft, and not to battleships alone. As to battleships, the United States, until limited in displacement by the Washington treaty, stressed in this type the characteristics of long steaming radius and protection. The policy of the United States has always been to endeavor to gain gun power superior to that on similar types possessed by foreign nations. To obtain these characteristics, speed was somewhat sacrificed. The reasons for these characteristics in the case of the United States ships was that this country has few outlying bases to link the home country with her overseas possessions, and to reach the probable theater of operations of a war the fleet would have to steam many thousands of miles with no ports into which to go for fuel and supplies. The ships had to be constructed to withstand damage which might otherwise force them to go to a base. In the case of the British capital ships we find that when their capital ships were constructed, the most probable enemy was close to home; therefore, long steaming radius was not necessary and the weights saved here could be put into machinery for higher speeds.
The Aircraft Carrier—The primary weapon of the aircraft carrier is the airplane. By the Washington treaty the airplane carrier is limited to a gun not larger in caliber than 8-inch, and the number of such guns it is permitted to carry is fixed by treaty and varies with the displacement of the ship. In addition they carry a rather large antiaircraft battery. Generally speaking, these ships are lightly armored. They depend upon their speed, antiaircraft battery and planes for their principal protection. They are floating landing fields for aircraft. The decks and elevators have to be so designed and arranged that planes can be rapidly brought to the flying deck and flown off, with as little interference as possible with planes returning to the deck from the air. They may be considered to be floating service stations where planes fitted with proper landing gear can land for fuel and servicing whether the planes belong to the particular carrier or not. For the same reasons as outlined under “battleship,” these ships must have long steaming radius. The decks are particularly vulnerable to gunfire and to bombing from the air, and once the decks are destroyed or badly damaged, it is readily seen that the ships lose their effectiveness as carriers; in such an event, their guns and speed make them valuable to perform the duties of a light cruiser, but they are too vulnerable for really effective cruiser work. The exception to this light protection is in those carriers converted from battleships and battle cruisers, but in all probability, the future carriers will be lightly armored, if armored at all.
The Light Cruiser—The Washington treaty limited light cruisers to a standard displacement of not more than 10,000 tons, and prohibited a battery of guns of greater than 8-inch caliber. The London treaty has further divided these ships into two subcategories: (a) those carrying guns greater than 6.1 inches in caliber but not greater than 8-inch; (b) those carrying guns of 6.1-inch or less caliber. The light cruisers of the future will carry armor to furnish them reasonable protection against guns not larger than those they themselves carry. The light cruisers of the United States must have moderately high speed, speed sufficient to allow them to escape from vessels more heavily gunned than themselves, as heavy a battery as is compatible with their speed and the long steaming radius they should have to meet our needs, and with the protection they must have to face an enemy with equal or less powerful battery.
The Destroyer—The primary weapon is the torpedo, although it carries a battery of guns not to exceed 5.1-inch caliber, and sometimes carries depth charges for offense against submarines. The standard displacement is limited by the London treaty to 1,850 tons. The vessel has high speed, and having no armor protection, it must depend upon its speed for protection.
The destroyer is the evolution of the torpedo boat. The torpedo boat was predicted to be the answer to the battleship. This failed to materialize, and the destroyer was built and enlarged as the answer to the torpedo boat, which it has driven from the seas; and besides it furnishes a torpedo vessel with sufficient seaworthiness to operate with the fleet.
The Light Mine Layer—This is essentially a destroyer hull from which the torpedo tubes have been removed and in their place have been installed racks for carrying and laying mines. As with the destroyer, she carries a gun battery. Her protection lies in her speed.
The Submarine—The primary weapon of the submarine is the torpedo. Some vessels of this type carry guns for use against surface craft when the submarine is caught on the surface and cannot submerge. The submerged speed is necessarily slow, while on the surface some submarines develop a speed in the neighborhood of eighteen knots. The defense of the submarine lies in submersion.
The Eagle Boat—The eagle boat was developed as a special measure during the World War to meet the submarine menace. The vessel has a speed of about eighteen knots and no protection. They are rapidly disappearing from use and probably no more will be constructed. It is a special type designed to meet a special need.
The Aircraft Tender—These vessels are usually employed to “mother” seaplanes. They are floating repair stations and storages for this particular type of plane. They are usually sent to a base with the seaplanes where they act as quarters for the crews of the planes and as service stations for the planes themselves. They have no flying-on decks as have the carriers, but the planes have to be hoisted aboard. When a number of seaplanes are to go from one port to another, the tender usually precedes them and prepares a base for their arrival. The tenders are usually placed in sheltered waters to care for planes as above described.
The Mine Sweeper—Ships of about 1,000 tons displacement, sturdy, and with excellent sea keeping qualities. They have a speed of about fourteen knots, and in appearance resemble a large ocean-going tug. They are very lightly armed with guns only. They are fitted to sweep channels or mined areas for the purpose of clearing those areas of anchored submarine mines.
Types of Combatant Ships Not in the United States Navy
The Battle Cruiser—The battle cruiser is a capital ship with a battery equal or nearly equal in caliber to that of the battleship. The difference between this type and the battleship lies in the fact that the battle cruiser has very high speed, about thirty- one knots, and comparatively light armor. Naturally, when the battery approaches that of a battleship and high speed is provided, the weight for protection must be reduced.
These are very powerful ships intended for operation tactically as a fast wing for the battleship force. Strategically they may operate to drive commerce raiders from the sea, or as advanced offensive scouts.
The only ships superior to them in battery and protection are the battleships, and the battle cruisers have the speed to accept or refuse action with the battleships should they fall in with such a type.
At the time of the Washington conference, the United States had six of these great vessels building. By the terms of the Washington treaty, four of these battle cruisers were scrapped, and two, the Lexington and Saratoga, were converted into aircraft carriers.
When the terms of the London treaty are carried out, there will be six of these vessels in existence—three in the hands of Great Britain, and three belonging to Japan.
The Destroyer Leader—The destroyer leader is a large destroyer. It carries practically the same offensive weapons as a destroyer, has the same speed, and has the same lack of protection. It is designed to operate with the destroyers, and is usually built one unit to a fixed number of destroyers. As the name implies, it is built to be the leader of a group of destroyers, and have the quarters for the accommodation of a squadron commander and his staff. Experience has taught that a destroyer cannot efficiently furnish the signaling facilities required by an officer commanding and directing the operations of a number of destroyers in action. The leader is designed to meet these needs.
Strategical and Tactical Uses of Types of Ships and Their Tactical Objectives
Strategic employment of the fleet is the placing of naval forces, not in contact with an enemy, in such position as will best contribute to the success of a campaign.
Naval tactics deal with the handling of naval forces in battle.
The tactical objective of a type of naval craft is the enemy type or vessel against which it is to direct its force.
In considering the strategical uses of types, it is difficult to consider the types as separated from the fleet as a whole; however, there are certain classes of ships which may rightfully be separated from the fleet for detached or independent duty. Outstanding in this consideration is the cruiser. And this includes the battle cruiser.
In determining the number of cruisers which a navy needs, the first consideration should be given to the number required for duty with the battleships, after that the numbers and types required for distant and independent duty.
The uses of detached cruisers in war may be stated to be against enemy commerce and lines of communication, the protection of our own lines of communication and commerce whether in our own bottoms or in neutral bottoms, and for strategical scouting. Particularly in the case of the United States, this work requires the most powerful cruisers we may build under the terms of the Washington treaty. The reason for this powerful cruiser for the United States hinges on the long distances they would be required to travel on the trade routes with no bases for repair and supplies, the small number of large cruisers to which this country has agreed to limit itself under the London treaty, and the fact that there are six battle cruisers in the world, none of which is in the possession of the United States. In 1922 when the United States signed the Washington treaty she surrendered the right to lay down battle cruisers before 1931, and by the London treaty she further surrenders the right to build them before 1936 should she desire so to do. It must be remembered that with the small number of large cruisers the United States has agreed to have, it will be very difficult if not impossible for the commander in chief of the fleet to distribute them so as to cover all strategical routes where they should operate. This deficiency means that should one be lost or so badly damaged that she would be required to return to a base for repairs, there will be no relief for her, unless a cruiser is taken from another area, and thus there will be a weakening of the force to cover some strategic area.
The cruisers on duty with the fleet should be of such design that they will be interchangeable with those away on distant missions. An occasion might arise where the fleet is more or less inactive at a base, during which time some of the cruisers attached directly to the battle fleet could be spared for duty on the trade routes, but if the fleet cruisers are of small, lightly gunned type, they will be useless on the service to which the large types are suited. In speaking of larger types, it must be remembered that this does not refer to large tonnage armed with small caliber guns, but to 10,000-ton cruisers armed with 8-inch guns.
While on a strategical scouting mission, should a cruiser meet an enemy vessel she should be able to destroy that vessel in order not to permit her own scouting formation to be broken. Vessels on a scouting mission in formation are not in a close formation, but the distance between units depends on the visibility and may be as great as sixty miles to ninety miles. Thus it is seen that there is no support or assistance at hand. If the scouting force is out with the mission to gain information as to the location and composition of an enemy fleet, the units of the scouting force should have the offensive power to pierce an enemy screen, which will most surely be composed of large cruisers.
The submarine is a type which also may be required to proceed long distances for the purpose of lying off enemy ports to attack hostile fighting craft entering or leaving those ports or bases, or to report such hostile movements. The submarine is the only type which can accomplish this task as she can hold station without being detected.
In the battle line, the battleship is the tremendously heavy fighting unit having the ability to deliver crushing blows and to withstand punishment which would destroy any other type. In a fleet action where we engage an enemy fleet having the same general types of ships as those which compose our own fleet, it is natural that we should exert every effort to destroy the enemy battleships. All units of our fleet must keep in mind that whatever action they take must be to support the battleships and aid them in accomplishing their purpose. The natural objective of the battleship then becomes the enemy capital ship. There may be intermediate objectives for the light forces, but these objectives are only for the support of the primary object which the battleship must accomplish.
The immediate objective of any type may vary in the course of an engagement. The cruisers have for their immediate objective the light forces of the enemy. They must drive off enemy light forces which may be endeavoring to prevent an attack by our destroyers on the enemy capital ships, or they may be required to provide security for our own battleships by breaking up an attack by enemy destroyers on our own capital ship line. They also must keep the commander in chief informed as to enemy movements which are out of his range of visibility. Cruisers may further be detailed to accompany aircraft carriers to guard them against attack by enemy light craft and to assist in the defense of the carrier against attack from the air.
The destroyer’s role in battle is to deliver torpedo attacks on the enemy capital ships and to protect our own battleships and aircraft carriers from submarine attack. While the primary objective of the destroyer is the enemy capital ship, she should also be used against enemy aircraft carriers, and, if opportunity offers, she should torpedo enemy cruisers.
The light mine layers in the fleet battle are usually divided into two sections, one section in the lead of the battle line, and one section well in the rear of the battle line, in both cases toward the enemy. If opportunity presents itself, they may lay mines where the enemy will pass through them. The presence of these vessels ahead of an enemy battle line may cause that line to change course whether the mines have been laid or only a threat made. Their presence in the rear of the battle line is to enable them to lay mines in case of a reversal of course by the enemy. In planting their mine fields they should exercise extreme caution, keeping the units of their own fleet fully informed as to the location of the fields so as not to embarrass their own force.
In the fleet battle the submarine is a weapon of opportunity. Due to its inability to develop much speed when submerged, it cannot be rapidly moved from one position to another in relation to the battle line. Another disadvantage of the type in connection with the fleet battle is the difficulty which a commander handling a fighting force would have in communicating with the submarine in order to direct its movements. Its primary objective is the enemy capital ship and aircraft carrier; however, if it has the chance to torpedo a cruiser, it should do so. It may be likened to a mobile mine field, but one whose mobility does not readily lend itself to rapid changes of position.
The aircraft carrier is a vessel whose capabilities have probably not been fully developed and which has not been tried in a fleet action. Its first objective, through the medium of the aircraft which it carries, is the enemy aircraft carrier. It should never expose itself to enemy gunfire if this can possibly be avoided. The objectives of the aircraft carrier change as the battle develops and progresses. Once the enemy carriers are located, our own carriers should endeavor to get bombers and torpedo planes into the air to proceed against them. At the same time, accompanying these bombers and torpedo planes, will go fighting planes for protection of the bombers against enemy fighting planes which will be sent out to frustrate attacks on the enemy carriers. The reason for this early attack on the enemy carriers is based on the fact that the force which gains and holds control of the air will have a great advantage in the general engagement, and one of the steps toward gaining this control of the air is to destroy the air base. The lighter planes flown from the decks of carriers cannot remain in the air for a long period of time due to their small fuel supply, and if there are no decks to which they can turn for refueling, they will be forced to land in the sea, where, even though they may not be destroyed, they will be useless.
Generally speaking, the battle for the planes will probably develop along the following lines: The observation or scouting planes will locate and report the enemy. Bombers and torpedo planes accompanied by a screen of fighting planes will proceed against the enemy carriers. Our own observation planes will take to the air for the purpose of observing gunfire. The bombers and torpedo planes will attack the enemy, concentrating on carriers, capital ships, cruisers, and submarines. At all times our own fighters must protect our own forces against depredations of the enemy air forces.
There is not sufficient room in this paper to go fully into the probable and possible employments of aircraft. This very brief outline must suffice.
The Fleet Cruising Formation (See plate XXXI)
When the fleet puts to sea in the time of hostilities, it must be given adequate protection against surprise attack. This protection is afforded through the medium of light forces so disposed as to give timely warning of the presence of an enemy, and in case the enemy proves to be a strong body, the warning must be given in sufficient time to permit the fleet to deploy into a fighting formation. If the contact is not with a strong enemy body, then the light forces must by their dispositions and strength be able to drive him off before he can gain information as to the strength and disposition of our own forces.
In a formation this security is afforded by an outer screen of light vessels, sometimes submarines, which upon the approach of an enemy warn the fleet. Backing up this outer screen may be a second screen of light vessels with ffie strength to drive off light vessels attempting to break through. The distance between the outer screen and the second screen must be sufficient to allow a number of the vessels of the second screen to concentrate to meet the threat. Backing up these screens will be concentrated an attack force, usually cruisers, or cruisers and destroyers, which will have sufficient power to meet a force of the enemy which has fought its way through the outer screens. A support consisting of a number of battleships screened by destroyers will be so placed that it can move to any threatened area. Inside of this screening disposition will be found the battleships, aircraft carriers, and vessels of the train. Finally will be a rear guard of cruisers, or cruisers and destroyers to protect the main body and the train from an overtaking force.
The whole formation must be arranged to permit rapid deployment of the force for the approach to battle or directly to the battle formation.
The fleet may proceed to sea without the train, but this should make little difference in the cruising formation, the principles of protection and mobility remaining unchanged.
The large slow-moving ships and the aircraft carriers in the cruising formation must be protected by an anti-submarine screen composed of destroyers. These destroyers completely surround the ships they are screening, zigzag with them, and are constantly on the alert to ram a submarine or to drop depth charges on one which may approach the formation.
If the fleet is making a long passage overseas, it is customary, in order to guard against surprise during the night or at dawn, by an enemy force approaching on approximately opposite course, to station a long line of cruisers ahead of the fleet and across its course. This scouting force proceeds on the fleet course at fleet speed. The distance between the scouts and the fleet formation is equal to the distance which the fleet will travel during darkness, plus the distance an enemy would probably travel in the same interval of time. For example: there will be eight hours of darkness; our fleet is steaming at ten knots, and it is estimated that an enemy force which might possibly be met will be steaming at twelve knots. During darkness our fleet will steam 80 miles and the enemy will steam 96 miles. The scouting line should be placed 176 miles ahead of the fleet formation. It will be readily seen that an enemy force which is beyond the vision of the scouts at dusk, but which pierces their line during darkness, will not be able to reach our fleet formation until after daylight. To doubly insure the fleet from surprise at the critical periods of dusk and dawn, an air search is usually sent up late in the afternoon and at dawn to make sure that there are no enemy craft in the vicinity.
The Approach to Battle
The scouts having reported and verified the presence of the enemy at sea in force, and having reported his position, composition of his force, course, speed, disposition, etc., it becomes necessary for the commander in chief to make such disposition of his forces as will permit him to bring his whole fleet into action without confusion. He must decide on what courses he will fight, and must put his fleet on an approach course which will intercept the enemy.
The cruising formation is changed to an approach to battle formation, and the course so shaped that the enemy will be intercepted and the fleet readily swung into battle line. In this approach he must allow for the security of his own force and guard against surprise. The approach formation is generally so laid out that, when the time comes to swing to the battle formation, a simple change of course by units or by subdivisions of the fleet will place the fleet on a line which is perpendicular to the direction in which the enemy bears, thus allowing all units to come into action simultaneously.
In the approach the battleships are usually in the rear and center of the formation, with the light forces disposed on each bow several thousand yards ahead and advanced toward the enemy. The numbers of ships in the divisions of light forces may vary with different situations.
In the approach the aircraft carriers are placed close enough to the battleships to be under the protection of their guns.
The Battle Formation (See plate XXXII)
In this formation the battleships must have a clear field for their gunfire, and light forces must make every effort not to blanket their vision by smoke or to interfere with their gunfire or movements.
Ahead of the battleships and toward the enemy will be placed part of the light forces. Nearest the battleships, and from five to ten miles in their advance, will be found the attack destroyer squadrons. A few miles beyond these attack squadrons will be the light cruisers intended to clear the way for our own attack squadrons in attacking the enemy battle line or for breaking up an attack by enemy destroyers on our own battle line. Well beyond the light cruisers will be the light mine layers.
The formation to the rear of the fleet is similar to that in the van. The reason for the light forces in the rear is to have a new van light force should the battle course be reversed. It can be readily seen that should the commander in chief reverse course and it be necessary for the light forces which were in the van before the course was reversed to get to the new van, the battle would probably be over before they could reach station unless the battleships slowed speed.
Plate XXXII illustrates two fleets, of nine capital ships each, drawn up as opposing fleets. The fleet in the background is
sending in a destroyer attack supported by light cruisers.
The reason for the destroyers being well advanced in the battle formation, is to permit them the shortest possible run to the place where they may most advantageously launch their torpedoes, and secondarily, to keep them out of the range of the secondary batteries of the battleships.
The aircraft carriers would normally be on the disengaged side of the battleships at sufficient distance to permit them to maneuver for launching and landing planes without interfering with other units of the fleet. They must be far enough back of the battle line so as not to be endangered by shots which pass over and beyond the battleships.
In order that the units and divisions of a large fleet may become a homogeneous whole, with the actions of the subdivision so coordinated that the maximum effort will be brought to bear against the enemy, constant practice and drill are required. These drills work up progressively through various stages of target practices, unit or subdivision tactical exercises, strategical and tactical scouting exercises, and grand maneuvers where the whole fleet is concentrated. An important part of the training is the indoctrination of personnel gained through courses at the Naval War College and other service schools, through work in the fleet, and through conferences of the admirals of the fleet with the commanding officers of ships. Each admiral and commanding officer must be so trained that he will recognize the object which the commander in chief is striving to accomplish, and so trained that he will put forth his best effort in the most helpful direction to support the commander in chief.
The supreme test is the fleet battle, and here will be demonstrated the degree of success which the strenuous training has accomplished.