is one of the best known and most appreciated functions of Army aviation. During the Korean War thousands of wounded were evacuated from the battlefield by Sioux (H-13) helicopters. Utility aircraft were also used effectively to expedite the flow of casualties to points of treatment and hospitalization. Helicopter ambulance units are at present equipped with the Chickasaw (H-19). Army Medical Service Corps officers, qualified as aviators and medical assistants, pilot these aircraft. In addition, suitable helicopters and fixed wing aircraft, assigned to combat organizations and tactical transport units, are used for casualty evacuation as required.

ARMY AVIATION STAFF ORGANIZATION. At Department of the Army level the Deputy Chief of Staff for Logistics is responsible for the logistical support of all Army aircraft. The Director of Army Aviation in the Office, Deputy Chief of Staff for Military Operations, has overall staff supervision and coordination of functions of the Army relating to Army aviation and formulation of policy thereon. At Headquarters United States Continental Army Command (USCONARC) an Army Aviation Special Staff Section has been established to advise the CG, USCONARC, on matters pertaining to Army aviation activities. Similarly, in each army, corps, and division headquarters there is an Army aviation staff section.

ARMY AVIATION UNITS. The following are the major units

Combat Aviation Company (Division). The aircraft allocated to a division are centralized in a combat aviation company, which performs for the division the functions described above. The combat aviation companies of the three types of division are quite similar in organization and aircraft strength. Each has about 50 aircraft (fixed and rotary wing) organized into a number of combat support flights, a surveillance or target acquisition section or flight, an artillery support flight, and a general support platoon.

Transport Aviation Battalion. Four of these are provided for each field army. A battalion consists of three light transport companies (20 Shawnee (H-21) or Choctaw (H-34) helicopters each), one medium transport company (16 Mojave

(H-37) helicopters), and one tactical transport fixed wing company (16 Otter (U-1A) airplanes). The mission of the battalion is to provide air transport to expedite tactical operations and logistical support in the combat zone. The battalions supplement the limited amount of transport aviation which is organic to divisions, and permit economy and flexibility in the use of Army aviation resources. A field army commander delegates control of one more of his transport battalions to his corps commanders as the situation dictates.

or

Sky Cavalry Battalion, Missile Command. This unit is organic to the missile command. Its mission is to perform reconnaissance through the use of a combination of ground and air reconnaissance elements over wide fronts and extended distances, and to provide security for its parent organization by surveillance and by air transport of the organic airborne reconnaissance platoon. The battalion makes use of photographic equipment, television, intrusion detection devices, air/ground radar, and CBR detection devices. A battalion has four sky cavalry companies; each contains observation, utility, and command type airplanes, observation and utility type helicopters, and drones.

Helicopter Ambulance Unit. This Medical Service unit is equipped with five utility type helicopters. It is used to evacuate, within the combat zone, casualties needing immediate definitive medical treatment. It may also be used to supplement or replace, for short periods, ground evacuation within the combat zone. Helicopter ambulance units will normally be assigned on the basis of six units per field army. Consolidation of these small units into company-sized units is planned.

Other Planned Army and Corps Units. In addition to the units described above, it is planned that one Army Aviation Company will be assigned to each field army. Its primary mission will be to provide aircraft to meet the command, liaison, and communications requirements of the army headquarters. Also it is planned that each corps will be assigned a Corps Aviation Company and a Corps Artillery Aviation Battery. The mission of the latter unit will include target acquisition and artillery observation.

Army Aviation Operating Detachment. This unit has no aircraft. Its task is to facilitate Army flight operations in the combat and communications zones by providing flight information and planning data, coordination of instrument flights, enroute navigation aids,

air traffic control, and operations service for Army aviation units. It is contemplated that such detachments will be assigned to corps, to army, and to major Army airfield installations in the communications zone.

The services are those branches of the Army whose primary task is to give technical or administrative support to the combat arms, or otherwise to serve the Army as a whole. Their names and tasks have changed over the years, as has also been true of the combat arms, and with the evolution of mechanized warfare their proportional numbers have steadily increased.

The distinction between "combat arms" (chapter 1 above) and "services" turns on their basic missions. Roughly speaking, it is the job of the arms to fight and it is the job of the services to support the fighting elements. But it must not be supposed that the combat arms are the only branches of the Army that do any fighting or come in contact with the enemy. Many of the services have troop units serving with combat divisions, or in other capacities at the fighting front, and all of them have representatives there. Officers and men of chemical, engineer, medical, signal, and other service units have at times had as heavy percentage losses in battle as the infantry and artillery that they were supporting.

At present there are fourteen services, divided into two main categories as follows:

BASIC BRANCHES. These are-
The Chemical Corps2
The Corps of Engineers
The Military Police Corps
The Ordnance Corps
The Quartermaster Corps
The Signal Corps

The Transportation Corps
The Adjutant General's Corps
The Finance Corps

The Women's Army Corps

SPECIAL BRANCHES. These are—

The Army Medical Service
The Chaplains

The Inspectors General

The Judge Advocate General's Corps

headquarters

Each service has a agency, headed by a chief, which is a part of the Department of the Army. The chief of a service has jurisdiction over his service in many fields of activity; but members or units of a service which are assigned to duty with a command are in general under the orders of its commanding officer, not of the chief of service.

The present chapter explains briefly the background, organization, and tasks of each of the services. More detailed descriptions of some of their duties are given elsewhere. For example, chapter 11 describes the Quartermaster Corps' function of feeding the Army; chapter 12, the construction and other duties of the Corps of Engineers; etc.

It is the responsibility of the Chemical Corps to provide support to the Department of Defense in the fields of chemi

cal, biological, and radiological warfare (CBR), including smoke, flame, and incendiaries.

HISTORICAL BACKGROUND. The need for a Chemical Corps arose out of the introduction, in World War I, of poison gases and similar devices as weapons of war. Gas (chlorine, released to drift downwind) was first used by the Germans on 22 and 24 April 1915, against limited sectors of the French and British (Canadian) fronts, with complete success. It has sometimes been claimed that, if the German High Command had had the vision to employ this surprise weapon on a broad front and as the spearhead of a major attack, they might have won the war then and there. As it was, the successes were only local, and the Allies promptly made and issued elementary protective masks. From then on to the end of the war, both sides developed and used various toxic gases such as mustard and phosgene, and devised improved means for delivering them by shells, bombs, etc. The Germans also introduced, and the Allies adopted, flame-throwers and incendiary bombs and shells.

When the United States entered World War I, five Federal agencies were working on various aspects of gas warfare: the Bureau of Mines, the Medical Department, the Ordnance Department, the Corps of Engineers, and the Signal Corps. To centralize these activities the Chemical Warfare Service, National Army, was created on 28 June 1918. It was charged with research, development, testing, and procurement of toxic gases and gas-defense appliances; the filling of gas munitions; chemical warfare training; and the formulation of doctrine governing the employment of toxic agents. Chemical officers were trained, and were assigned on all army, corps, and division staffs, with the result that the entire Army was equipped and trained in defense against gas attack. The Chemical Warfare Service was made a permanent branch of the Regular Army by the National Defense Act of 1920. In the interwar period it shrank from a war peak of 20,518 officers and men to a one-time low of less than 500. It devoted its efforts mostly to research and to supervision of training.

Expansion began again before Pearl Harbor. Lend-lease shipments were started, new manufacturing facilities

were built, and many development projects were speeded up. By 1940 our five major prewar achievements in chemical warfare were ready for production: a rifled 4.2-inch mortar; a companion shell; a smoke and chemical spray tank, for the rapid laying of smoke screens or heavy gas concentrations by aircraft; a substance for impregnating the uniform to protect against mustard gas; and a new gas mask, which could be worn longer than earlier issues and with less discomfort, and which gave a much larger field of vision.

When we entered the war, the first task of the Corps was to prepare for the defense of our armed forces and population against a possible chemical attack, and also to prepare for a retaliatory counterattack if the enemy started gas warfare. CWS officers were assigned to staffs at all levels; over 400 CWS troop units, air and ground, were activated; some 35,000,000 civilian and military gas masks, and large amounts of other protective devices, were made and issued. As the war progressed, it became clear that these measures were effectively deterring our enemies from using toxic gases if they had had that intention, and probably would continue to deter. Therefore other types of chemical equipment, accepted by both sides as legitimate weapons, came to play the principal part in the CWS program. The most important were aerial incendiary bombs, the 4.2-inch chemical mortar, and smoke munitions.

Aerial Incendiary Bombs. These became the largest single class of supplies in the CWS production program. They played a dominant role in crippling enemy production and transportation in our air raids of 1943-5.

The 4.2-Inch Chemical Mortar. This mortar was developed as a smoke or gas projector, but was extensively used with high explosive and white phosphorus shells, over 4,000,000 of which were fired during the war. In Sicily in the summer of 1943, and thereafter in all major operations in the European and Pacific theaters, it was a spectacular success as a heavy weapon for close infantry support. A total of 25 chemical mortar battalions and 2 separate com

panies saw combat duty. One of these had 508 days of combat out of 668 days spent in the European theater; was in 1 airborne and 5 amphibious operations; fired some 500,000 rounds; and received 3 DSCs and 876 Purple Hearts.

Smoke Munitions. These included smoke grenades and pots, airplane spray tanks, mobile mechanical generators, and the like. They were employed for numerous tactical and rear-area screening missions. Smoke generators laid fog blankets to obscure troop movements, to conceal harbor areas from enemy bombers, and to conceal critical frontline tactical areas from enemy air and ground fire. Floating smoke pots provided cover for naval operations. Colored smokes were used for signaling. White phosphorus grenades and shells provided a combined screening and antipersonnel weapon.

POSTWAR DEVELOPMENTS. The Chemical Warfare Service was redesignated the Chemical Corps by Act of Congress 2 August 1946.

During the Korean conflict, both the Infantry and the Marines made use of the 4.2-inch mortar in their heavy weapons companies. Chemical mortar battalions supported units not equipped with this weapon. In addition to these battalions, many Chemical Corps technical and service units saw combat duty, and permissible chemical munitions were widely used. Napalm (jellied gasoline), as an incendiary, became one of the most common weapons in the campaign.

THE CHEMICAL CORPS TODAY. The Corps has been extensively reorganized along functional lines, similar to those obtaining in many civilian chemical industries. Its chief duties today are the development of new offensive and defensive devices, supply activities, and training for chemical, bacteriological and radiological (CBR) warfare.

RESEARCH AND DEVELOPMENT FACILITIES. These include laboratories, proving grounds, and pilot and semiworks plants. Close liaison is also maintained with civilian scientific and industrial plants and programs.

OFFENSIVE AND DEFENSIVE DEVICES. Among the research and development projects completed since the close

of the Korean conflict are: a one-shot portable flamethrower for use in closerange combat; an automatic field alarm to detect nerve gases; a fiber diffusion board, similar in appearance to fiberboard, which can be used as a liner in buildings to provide protection from all known chemical and biological warfare agents; an aerosoloscope to measure and count microscopic airborne germs, dust, and moisture particles; an automatic colony counter for use by bacteriologists in counting bacterial colonies; and a radically new protective face mask, which eliminates the protruding cheek canister filter unit.

PEACETIME BENEFITS. As can be seen from these examples, the work of the Corps benefits not only military preparedness but also society in general. In fact, throughout its history it has made discoveries in medicine, animal and crop diseases, immunology, crop protection, insect control, and other scientific fields which are of inestimable value to our nation. Many protective items recently developed by the Corps are adapted for civil defense use, in cooperation with the Federal Civil Defense Administration. Among them are a civilian protective mask, a hospital protective mask, an infant protector, and a mask-to-mask resuscitator. (See also chapter 31.)

SUPPLY. The Corps is required to maintain adequate supply readiness in the field of CBR warfare. This calls for properly balanced reserves of a wide variety of equipment and supplies, with a ready mobilization production base. The Corps buys some items from private industry, and makes others in its arsenals. Under the "single manager plan," it serves not only the Army but also the Navy and Air Force. Principal categories of supply are the following

Chemicals, including general cleaning and solvent chemicals, acids and alkalies. Gases, including irritant, persistent, and nonpersistent agents.

Smokes, including both colored and screening smokes.

Incendiary agents.

Protective equipment, including both individual and collective protective items such as protective masks; protective ointments; animal protective items; decontamination equipment; and detection items to give warning of chemical or biological contamination of areas, food, or water.

Gas cloud materiel, generators and accessories.

Training and maintenance equipment.