"US Army Air Defense Digest, 1972"

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This is a scanned and OCR'd version of the unclassified "US Army Air Defense Digest, 1972".

Bob Campbell (bcampbell12333@yahoo.com) kindly lent this book to me. Thank you Bob.
(The book has been returned! :-)

The first 64 pages have been scanned. The remaining pages deal with Hawk, Chaparral, Vulcan, Redeye, Safeguard Ballistic Missile Defense System, and other weapons. Although interesting, these are not included in this web page.

*** Please note - scanning and OCR (Optical Character Recognition) is an imperfect art. My OCR software is probably not "state of the art". There were frequent obvious errors - some of which could be interpreted as slurs or insults. An example was a frequent mis-conversion of "CONAD" into "GONAD". This presenter apologizes for any errors - and suggests that the viewer retain a healthy skepticism of this conversion.


UNITED STATES ARMY AIR DEFENSE DIGEST
CONTENTS

UNITED STATES ARMY AIR DEFENSE DIGEST

CONTENTS

. . page
CHAPTER 1. AIR DEFENSE DOCTRINE AND PROCEDURES .
. Army Air Defense Operations 1
. North American Air Defense Command 1
. United States Army Air Defense Command 17
. US Air Defense in North Atlantic Treaty Organization 20
. Air Defense in Pacific Area 21
. Air Defense in the Field Army 24
. Air Defense Artillery Maintenance 27
. Electronic Warfare 28
. Identification, Friend or Foe 31
. Air Defense Artillery Communications 33
CHAPTER 2. AIR DEFENSE ARTILLERY CONTROL SYSTEMS .
. BIRDIE (AN/GSG- 5) 38
. Missile Monitor (AEˇJ/MSG-4) 40
. Missile Mentor (AN/TSQ-51) 43
. Three-Dimensional Radar 46
. Radar Netting System 47
. Data Converter AN/GSA-77 48
. Evolution of Defense Acquisition Radars 50
CHAPTER 3. CURRENT AIR DEFENSE ARTILLERY WEAPON SYSTEMS .
. General 52
. Improved Nike Hercules 52
. Air Defense Artillery Engagement Simulator; Guided Missile System Radar-Signal Simulator Station AN/MPQ-T1 (Nike Hercules) 62
. Hawk 64
. Air Defense Artillery Engagement Simulator; Guided Missile
System Radar-Signal Simulator Station AN/TPQ-21 (Hawk)
76
. Chaparral 77
. Vulcan 78
. Forward Area Alerting Radar 81
. Air Defense Artillery Automatic Weapons Employmenc 83
. Older Air Defense Artillery Automatic Weapons 83
. Redeye 86
. Safeguard Ballistic Missile Defense System 91
. Antiair Warfare Weapons of the US Navy and US Marine Corps 100
. Air Defense Weapons of the US Air Force 103
CHAPTER 4. PROPOSED AIR DEFENSE ARTILLERY SYSTEMS .
. SAM-D. 107
. Command, Control, and Coordination System AN/TSQ-73 109
. Three-Dimensional Acquisition Radar 110
CHAPTER 5. AIR DEFENSE ARTILLERY TRAINING MATTERS AND INSTRUCTION .
. Nonresident Instruction 111
. Training Literature 113
. Training Films and Graphic Training Aids 116
. MOS Evaluation Tests 119
. Innovative Techniques for Missile Electronics and Automatic Data Processing Training 119
. Guided Missile Systems Officer Course (4F-1181) 121
. Allied Student Program 123
CHAPTER 6. UNITED STATES ARMY AIR DEFENSE ACTIVITIES .
. United States Army Air Defense School 129
. US Army Combat Developments Command Air Defense Agency 136
. US Army Air Defense Board 137
. 1st Advanced Individual Training Brigade (Air Defense) .
. 11th Air Defense Artillery Group 138
. US Army Air Defense Human Research Unit 138
. McGregor Guided Missile Range 139
. Keeping Abreast of Technical Developments 140
. AirDefense Center Team Conference 140
APPENDIX Abbreviations 141

Chapter 1

Air Defense Doctrine and Procedures

All services--Army, Navy, and Air Force--are involved in air defense operations. Current doctrine and operational procedures provide for integration of the weapon capabilities of all services.

ARMY AIR DEFENSE OPERATIONS

AUTHORITY

Specific authorization for the Army to engage in air defense operations is derived from the National Security Act of 1947, as amended, and Joint Chiefs of Staff Pub. 2, United Action Armed Forces (UNAAF), November 1959. These directives assign the Army primary functions as follows: "To organize, train, and equip Army forces for the conduct of prompt and sustained combat operations on land--specifically, forces to defeat enemy land forces and to seize, occupy, and defend land area." UNAAF assigns the Army the following air defense missions: "To organize, train, and equip Army air defense units, including provision of Army forces as required for defense of the United States against air attack, in accordance with doctrines established by the Joint Chiefs of Staff.

CONCEPT OF AIR DEFENSE OPERATIONS

The broad principles of Army air defense doctrine are stated in FM 44-1, U.S. Army Air Defense Artillery Employment. The provisions in FM 44-1 apply to US Army air defense artillery units with a unified command or serving in a combined force. The policies and procedures prescribed by the joint air defense commander will prevail when they conflict with doctrine and procedures described in FM 44-1.

NORTH AMERICAN AIR DEFENSE COMMAND

The North American Air Defense Command (NORAD) is a combined command exercising operational control of forces allocated for air defense of Canada, Alaska, and the continental United States. Its mission is "to defend the North American Continent against an attack. " Headquarters NORAD, located at Colorado Springs, Colorado, prepares operational plans, conducts tactical exercises and readiness tests, and coordinates plans and requirements for new air defense weapons. It is the supreme headquarters for directing the air defense of North America in the event of war.

EVOLUTION

NORAD was formed in September 1957 following an agreement between the governments of Canada and the United States which, in effect, was official recognition of the fact that air defense of the two countries is an mdlvisible task. A high-level Canadian-United States committee (Military Cooperation Committee) drew up an emergency plan far the common defense of North America and directed that air defense organizations of the two countries prepare detailed emergency air defense plans. The first of these was issued in 1950.

Early in 1954, the same committee authorized a combined planning group of representatives from the Royal Canadian Air Force and the US Air Force Air Defense Command. Studies conducted by this group indicated that the best air defense of North America was an integrated defense, with forces of both countries operating under a single command, responsible to both governments. Following the completion of another study 2 years later which had the same conclusions, integration of operational control of the two forces was recommended .

In the meantime, the two countries had gone ahead with the development of a joint radar warning network. Together, they built the Pine Tree line of radars across southern Canada. Canada started constructingthe mid-Canada line, and the United States began the distant early warning (DEW) line across the northern rim of the continent. Conditions for operating and manning these lines were mutually agreed upon.

Thus, by 1957, there had been a considerable history of joint planning, coordinating, and sharing, and the need for further integration had been recognized. In August of that year, the United States Secretary of Defense and the Canadian Minister of National Defence announced that the two governments had agreed to establish a system of integrated operational control of air defense forces for North America and an integrated headquarters. On 12 September 1957, NORAD was established, followed by the signing of an official agreement by both countries on 12 May 1958.

The Commander in Chief, North American Air Defense Command (CINCNORAD), was to be responsible to the Chief, Defence Staff of Canada, and the Joint Chiefs of Staff of the United States. The agreement further stipulated that the appointment of CINCNORAD and his deputy had to be approved by both governments and that both would not be from the same country.

NORAD FORCES

NORAD has no organic fighting elements of its own, but is furnished combat-ready forces, including Reserve and National Guard forces, by three component commands (fig 1): US Army Air Defense Command(ARADCOM), US Air Force Aerospace Defense Command (USAF ADC), and Canadian Forces Air Defence Command (CF ADC), plus the air defense forces of the Alaskan Command. CINCNORAD exercises operational control over all air defense forces attached or otherwise made available by component commanders and the Alaskan Command.

ARADCOM furnishes Nike Hercules missiles (high-altitude, surface-to-air) and Hawk missiles (low- and medium-altitude, surface to-air). Under this command are the US Army missile units protecting the key population and industrial centers of the United States.

Most of NORAD's fighter-interceptor squadrons are provided by the USAF ADC. This component also contributes Bomarc surface-to-air missiles, CONUS radar squadrons, and early warning airborne radars. USAF ADC is responsible for the Ballistic Missile Early Warning System (BMEWS) and SPACETRACK (a part of the Space Detection and Tracking System(SPADATS)), providing NORAD important information about ballistic missiles and orbiting space objects. The Air National Guard provides interceptor squadrons on full-time assignment to NORAD through USAF ADC.

Figure 1. NORAD/CONAD operational control structure.
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The CF ADC provides fighter-interceptor squadrons and long-range radars which contribute heavily to performance of surveillance, detection, and identification functions.

Alaskan air defense forces are made available to CINCNORAD for operational control. This force is not a component of NORAD. The force, consisting of Army and Air Force AD weapons, are part of the Alaskan Command (a unified command). Commander in Chief, Alaska (CINCAL), has a dual role. He is the commander of the Alaskan Command and also the commander of the Alaskan NORAD region. The geographical boundaries of the Alaskan Command and Alaskan NORAD region are the same.

The US Navy's space surveillance system (NAVSPASUR) furnishes information to NORAD on orbiting space objects. The US Navy would also provide augmentation forces upon direction of the Joint Chiefs of Staff.

The Continental Air Defense Command (CONAD) is a unified command made up of US personnel within the NORAD structure. This organization gives the US a capability of unilateral action where strictly United States interests are involved. Accordingly, the mission of CONAD is aerospace defense of Alaska, Greenland, and the continental United States (CONUS), and Mexico if requested by the Mexican Government. The senior American officer in NORAD is the Commander in Chief, Continental Air Defense (CWCONAD). If CINCNORAD is an American, he also is CINCONAD. If CINCNORAD is a Canadian, then the Deputy CINCNORAD is CINCONAD.

OPERATIONAL PROCEDURES

To accomplish its mission, NORAD is guided by these air defense principles: hit the enemy as far out as possible; increase the pressure as he continues; complicate his tactical problem by empl,ying a family of weapons to perform low, medium, high, close-in, and distant missions; and realize optimum economy and efficiency of effort through centralized direction and decentralized execution of the air battle.

NORAD must guard against manned bomber attack as well as ballistic missile attack. It must watch over the North American Continent from treetops to beyond the atmosphere. Currently, the North American Continent is divided into eight regional areas (fig 2) of air defense responsibilityˇ Each region commander is responsible to CINCNORAD for all air defense activity within his designated area.

Figure 2. NORAD operational boundaries.
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Each NORAD region is the basic unit for decentralized fighting of the air battle. Regions that cross the international boundary are manned jointly by United States and Canadian personnel. The sizes of regions vary depending generally on the amount of air traffic and number of vital target areas located within each region.

To perform its mission, NORAD must accomplish four basic actions: detect the presence of airborne objects, aircraft, or missiles; identiiy them as friendly or hostile; intercept and examine those not identified as friendly; and destroy those identified as hostile, using interceptor aircraft or air defense missiles.

NORAD employs several detection and warning systems, each designed to detect one of the three possible threats. The northernmost detection system is BMEWS. The three BMEWS stations(Thule, Greenland(fig 3), Clear, Alaska(fig 4) and Flyingdales Moor in Northern England) employ electronic systems providing detection and early warning of attack from enemy intercontinental ballistic missiles (ICBM).

Figure 3. NORAD BMEWS site at Thule, Greenland.
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BMEWS was made possible by scientific developments in the electronics field. The system uses huge radars, approximately the size of a football field, which can detect a missile at a distance of 3,000 miles. The power required for a single station would meet the electrical needs of a small city.

The heart of the BMEWS detection system is a combination transmitter-receiver which transmits an extremely brief burst of energy many times each second in narrow fans of radiofrequency energy at two different degrees of elevation. As a missile passes through these fans, it reflects energy to the station, enabling the coordinates of flight to be recorded. From a set of coordinates, the trajectory can be plotted and the impact point, time, and point of launch calculated. Data processing equipment at the site rapidly computes the data and flashes a warning to NORAD.

[I did not include the photo, figure 4., on page 6]

Another detection system is the manned bomber sunreillance network, composed of land-based radar networks (fig 5) and Air Force planes. The first line of radars begins in the far north with the Distant Early Warning (DEW) line (fig 6). This radar fence, which stretches from the eastern shores of Greenland across the Canadian Arctic to Western Alaska, provides initial warning of attack by manned bombers. A ground-based radar system, called contiguous coverage, is extended out to sea off the southeast coast by Air Force radar planes (fig 7). All of these systems are joined together by a communications network terminating in the NORAD Combat Operations Center at Colorado Springs, Colorado.

Figure 5. NORAD radar detection system.
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[I did not include the photos, figures 6 and 7, on page 8]

Another part of the NORAD detection and warning system is the Space Detection and Tracking System (SPADATS) which keeps track of all manmade objects in space. Through a global system of radar, radio, and optical sensors, the system brings under NORAD operational control space detection and tracking resources available to the military. Civilian and government scientific agencies throughout the free world contribute to the system on a cooperative basis.

Primary military members of the SPADATS are the USAF SPACETRACK system and US Navy's NAVSPASUR. SPACETRACK provides tracking information through a series of USAF sensors (radar, optical, and electronic). The CF ADC provides inputs from an optical sunreillance device, the Baker-Nunn camera (fig 8). NAVSPASUR is composed of three powerful transmitter stations and six receiver stations alternately spaced across the southern United States from California to Georgia. Data from this network are furnished to NORAD Space Defense Center(SDC) computers through the system's headquarters and opei-ations center at Dahlgren, Virginia.

Figure 8. Baker-Nunn camera.
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Space tracking information from this widespread system flows into the SDC (fig 9) at Colorado Springs wnere giant digital computers digest reams of complex orbital data on space objects.

Figure 9. Space Defense Center at NORAD Headquarters.
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The wide variety of data received from the numerous sources enables the SDC to provide complete and timely cracking information on manmade objects in space. SDC also maintains a running catalog, constantly revised and updated, on space traffic. Thousands of observations are received daily and are used to refine existing orbital characteristics of hundreds of objects. This includes not only payloads but space junk, such as burned-out boosters and wires the size of a lead pencil.

Once the computers have digested all the tracking data and produced their findings, the information can be transmitted to the battle staff area in the adjacent NORAD combat operations center by closed-circuit television.

Identification is one of NORAD's most difficult problems, caused chiefly by the large amount of air traffic in the United States and Canada. On the average, there are approximately 1,200 overwater flights daily and an estimated 200,000 internal flights .

Aircraft penetrating the North American Continent enter air defense identification zones (ADIZ) established around and throughout the continent to assist in identification processing. Any aircraft originating from an oversea area must enter an ADIZ within 20 miles of a predetermined point and within 5 minutes of an estimated time, based on the pilot's flight plan filed at his takeoff point and sent ahead to the Federal Aviation Administration (FAA) inthe United States and Department of Transport (DOT) in Canada. This information is relayed to appropriate NORAD region control centers (NRCC) and used for correlation when the track is acquired.

If an aircraft enters an ADIZ, but is not within prescribed limits, it is declared an unknown and interceptors may be scrambled to make positive visual identification. The ADIZ system is part of the NORAD identification process known as flight plan correlation.

Under combat conditions, the identification process would be somewhat simplified when provisions of emergency plans and security control of air traffic and air navigational aids (SCATANA) are placed in effect. SCATANA provides for orderly grounding of nonessential aircraft and establishing military control over radio navigational aids.

In view of the large number of aircraft flights taking place within NORAD airspace in any given 24-hour period, it is a rare day when none of these appear at the NORAD combat operations center as unknown. The average number of unknowns in the system has steadily declined over the years untir now the number isapproximately 40 per month. Of these, it is common to find two or three instances where interceptors are scrambled recalled before intercept because of the identity being established by further communication checks.

The regular fighter-interceptor squadrons (fig 10) of the NORAD system, in an emergency, would be augmented by available fighter aircraft of the US Navy, US Marine Corps, US Air Forces, Air National Guard, and interceptor training units of the CF ADC. All of these forces are highly mobile and constantly practice dispersal and forward base deployment.

NORAD COMBAT OPERATIONS CENTER

Nerve center of the North American Air Defense Command is the Combat Operations Center (COG) situated in Cheyenne Mountain, south of Colorado Springs (fig 11). The COC is housed in steel buildings beneath more than a thousand feet of solid granite. The main part of the COC is a three-story building complex (fig 12) constructed within the intersecting chambers. It includes 200,000 square feet of floorspace to accommodate a maximum of 1,800 people. The COC is virtually safe from thermonuclear attack (fig 13). It is from the COC that the first warning of an attack on North America would come. If such an attack should come, the air battle for survival of the United States and Canada would be directed from the COG.

Figure 10. Phantom jets of NORAD patrol the Alaskan skies
Figure 11. Cheyenne Mountain, showing the entrance to NORAD COC

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Figure 12. Buildings housing NORAD COC rest on these mammoth springs.
Figure 13. Protecting the entrance to NORAD COC from nuclear blast are these gigantic 25-ton swinging doors

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Data are received in the COC from the huge complex of radar stations, interceptor squadrons, missile sites, space tracking and ballistic missile warning units, and NORAD regions and are stored in a large digital computer. Here, too, information is received from other sources, such as the Strategic Air Command (SAC), naval forces off both coasts, the Pentagon, and the Department of National Defence in Canada.

This information is displayed on an electronic wall display system (fig 14). The system permits almost instantaneous observation of the positions of aerospace and seaborne objects thousands of miles away and over any part of the continent covered by radar networks. It flashes surveillance information on large, theater-like screens for easy observation.

Figure 14. Underground COC showing battle staff and main display boards during a test exercise.
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Included is a map of North America, the surrounding oceans, Greenland, Iceland, parts of Siberia, and the Caribbean islands. Symbols show the location and direction of travel of all aircraft of special interest to NORAD. These may be strategic friendly elements or a commercial or military aircraft that for one reason or another is classed as an unknown until positive identification is made. NORAD is interested in unidentified submarines, friendly aircraft carriers, Soviet fishing trawlers, and air activity over Cuba and Siberia. All this is presented on the main display with special coded symbols that provide a variety of information about the subject.

To the right of the main display is the weapon status hoard. This is associated with the main display, and information on the board is received, processed, and displayed automatically. The top part of this board, referred to as the "commander's box score, " shows at a glance the number of hostile aircraft in the NORAD system, the number of unla~owns, the weapons committedto these tracks, the kills made, and NORAD losses. Below is a listingof worldwide major military commands and their defense readiness conditions. The bottom part of the status board shows the number of weapons available to NORAD on a 5-minute alert, including fighter-interceptors and surface-to-air missiles.

Figure 15. NORAD space-watching activities are conducted in the Space Defense Center.
Figure 16. Located at Eglin Air Force Base, this "phased array" radar provides the SDC with current satellite information.

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Other types and sources of information are available on call. The weather forecast office in the COC is manned with trained meteorologists who are always on duty and ready to provide the latest weather information, either in person or through the closed-circuit television network, to monitors in front of each member of the battle staff. SDC is located in the COC (fig 15) and can provide information (fig 16) to the battle staff either by a per sonal briefing or through the television system.

SEMIAUTOMATIC GROUND ENVIRONMENT

Conduct of an area air defense battle requires a vast amount of information, dependable communications, and coordination among many organizations. Receiving this information, processing it, and using the necessary instructions in the limited time available proved impossible for unaided human beings, and an electronic air surveillance and weapon control system was devised to do the job. This system, called semiautomatic ground environment (SAGE), receives information, processesit, and communicates instructions to those concerned.

Figure 17. SAGE data flow.
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Figure 17 shows the flow of data to and from the NORAD region control center (NRCC) in the air defense organization. Data are transmitted automatically to the NRCC from ground-based search radars and, on demand, from height-finder radars. Information on weapon status, weather, and airborne early warning is received by telephone, radio, and teletype and is programed into the computer. Similarly, data from the NRCC are transmitted automatically to direct Bomarc missiles and aircraft equipped with data link receivers to hostile aircraft. Digital data transmission is used to pass hostile track information to Missile Mentor (AN/TSQ-51) or battery integration and radar display equipment (BIRDIE) command, control, and coordination systems for action by Nike Hercules and Hawk fire units. Selected data are automatically sent to adjacent NRCC's. Manned interceptors, not equipped with data link, are directed to the hostile aircraft by voice (ultrahigh frequency (UHF) radio). Telephone, teletype, and radio are used to pass information to civil defense agencies, SAG, and other headquarters.

UNITED STATES ARMY AIR DEFENSE COMMAND

The US Army Air Defense Command (ARADCOM) is both a major combat command of the US Army and a component of NORAD. As a member of the two-nation air defense organi zation, ARADCOM is assigned the mission of providing combat-ready Army forces to the Commander in Chief, NORAD, for the air defense of designated strategic and metropolitan target complexes. The mainstay of ARADCOM's weapon inventory is nuclear-capable Nike Hercules surface-to-air missiles. Nike Hercules missiles are augmented by nonnuclear Hawk missiles, currently deployed in defense of the Homestead-Miami and Key West areas in southern Florida. Nike Hercules is effective even at altitudes up to 150,000 feet and the Hawk from treetop level to 38,000 feet.

HISTORY

The history of ARADCOM dates from 1 July 19j0 when it was established as the Army Antiaircraft Command. However, it was 10 April 1951 before all antiaircraft artillery units located within the continental United States and allocated to its defense were placed under the command jurisdiction of the newly formed command.

The command's early armament consisted of 90-mm guns of World War Il vintage and 120-mm guns. Later, the 75-mm Skysweeper, last of the conventional antiaircraft artillery weapons to be developed, was added to the command's arsenal. The first surface-to-air guided missile to be phased into the Army air defense system was the Nike Ajax, which became operational on site in the Washington-Baltimore defense in May 1954. On 21 March 1957, in recognition of its growing combat-ready, surface-to-air guided missile force, this command was redesignated the US Army Air Defense Command.

In June 1958, ARADCOM's first Nike Hercules unit attained operational readiness in the Chicago defense. Since that time, all of the command's missile sites have been converted to the second-generation Nike Hercules.

ARMY NATIONAL GUARD

The Department of the Army authorized the Army National Guard to convert 32 antiaircraft artillery battalions, then equipped with conventional guns, to Nike Ajaw missile battalions in 1957. The 4th Missile Battalion (Nike Ajar), 251st Artillery, California Army National Guard, was the first National Guard surface-to-air guided missile battalion integratedinto the active continental United States defense mission. This unit assumed around the-clock operations at four battery sites in the Los Angeles area on 14 September 1958. At the completion of the phased training program, the Army National Guard was furnishing 76 batteries in 14 states, defending 15 areas. These were the first US Reserve Forces with modern surface-to-air missiles.

In May 1962, the first of the Army National Guard Nike Ajax units were phased out and started retraining to operate and maintain the second-generation Nike missile, the nuclear capable Nike Hercules. Four units of the Maryland National Guard were selected for the initial conversion to Nike Hercules, becoming operational on 11 December 1962.

The last four Nike Ajax sites manned by the National Guard were phased out in May 1964 at Norfolk, Virginia. The final stages of the Nike Hercules conversion program were completed in 1965 with 48 Army National Guard batteries, representing 16 states and defending 18 areas, participating in the on-site program. Since that time, due to threat reassessments and budget cuts, the number of ARADCOM batteries, both National Guard and Regular Army, has been reduced significantly.

Guardsmen assume full operational responsibility for manning the sites around the clock. Full-time personnel man the equipment 24 hours a day, keeping it in constant readiness. This cadre of full-time specialists is capable of initiating effective fire on the enemy without additional personnel. Remaining members of the units are citizens of the community who retain their military skills by attending regular drills with their units. If an air attack should occur, they would report immediately to their assigned units.

These Army National Guard units, although an integral part of the air defense system when they become operational in wartime, retain their identity as State units under the command of the governors of their respective states in peacetime. ARADCOM has been assigned responsibility for training supervision and support of these units. In event of an emergency reqlunng use of these units in a combat role, operational command would be exercised by CINCNORAD through the Commanding General, ARADCOM.

OPERATIONS

Administrative and training supervision over the widespread defenses is exercised by ARADCOM regions. Figure 18 shows the region boundaries, region headquarters, and the location of ARADCOM defenses. Region headquaaers and their locations are as follows:

The combat effectiveness of ARADCOM units is determined by certain indicators, such as engagement simulator training, operational readiness evaluations, defense combat evaluations and technical proficiency inspections (TPI). All indicators must be considered together to determine the effectiveness of units. ARADCOM materiel readiness evaluation teams aid the units in maintaining a combat-ready posture.

Figure 18. ARADCOM region boundaries and region headquarters.
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ARMY AIR DEFENSE COMMAND POST IN NORAD OPERATIONS

The wide dispersion of ARADCOM sites poses a unique problem that requires a specific control and communications system. At the heart of this control and communications system are the Army air defense command posts (AADCP). Tactical supervision of Nike Hercules and Hawk fire units is exercised from AADCP's. An AADCP can use a semiautomatic electronic command, control, and coordination system or be manually operated. The command, control, and coordination system used is either of two transportable systems, the BIRDIE (AN/GSG-5) or Missile Mentor (AN/TSQ-51).

Most AADCP's are linked to an NRCC by digital data and voice, and to their associated fire units by data links, voice lines, and radio. In addition, some AADCP's are linked to the NRCC by teletypewriter lines. Normal operation calls for semiautomatic data processing from NRCC to fire units through the AADCP's, with backup facilities available for emergency and supplemental operations. Command, control, and coordination systems provide for complete semiautomatic operation with fire units when SAGE data are cut off. Facilities are also available for manual plotting and voice telling if needed.

Those AADCP's tied to an NRCC automatically receive early warning, aircraft identification, and other data. These data are collected by the AADCP's, improved when possible, and transmitted to fire units. In NORAD regions equipped with SAGE where Missile Mentor or BIRDIE command, control, and coordination systems are in operation, NORAD has prescribed five levels of operations for weapon control for SAGE air defense artillery operations.

In level I operations, the primary NRCC (fig 19) supervises the air battle for combat elements; l.e. vectoring fighter interceptors, programing and firing Bomarc missiles automatically through the SAGE computer, and supervising and monitoring SAM engagements through the AADCP. Reference data (symbology) is furnished over the automatic data link (ADL). Level 1 also indicates to the commander that all backup facilities are fully operational(i.e., the NORAD control center (NCC)).

Level 2 indicates that the primary NRCC is still controlling the air battle, but that the backup facilities are degraded to some extent.

Level 3 indicates that the primary NRCC is still controlling the air battle, but that the backup facilities are not operational or are not available.

Level 4 indicates that the NRCC is no longer controlling the air battle and that the combat elements are being controlled by the backup facility (NCC). In each region there are at least two NCC's which can furnish limited early warning and identification to fhe AADCP as well as vector interceptors and program and launch Bomarcs.

Level 5 indicates that the air battle is being conducted autonomously by the AADCP's (or fire units) and manually directed fighter-interceptors. Level 5 indicates that the SAGE and BUIC control systems are ineffective; therefore, Bomarc can no longer be employed because Bomarc must be programed and directed by a computer. Autonomous operations are predicated on the complete loss of communications between the AADCP and all higher headquarters m the NORAD chain or between the fire unit and its AADCP. It must be emphasized that this loss is a total loss of communications and not a temporary outage due to natural causes (floods, hurricanes, etc.). In autonomous operations, the Army air defense commander(AADC), or the battery commander, assumes full responsibility for the air battle, using the very limited identification means available to him.

US AIR DEFENSE IN
NORTH ATLANTIC TREATY ORGANIZATION

Specified United States air defense artillery units in Europe are part of the North Atlantic Treaty Organization (NATO) integratedair defense system of Allied Command Europe (ACE), one of the military commands of NATO. The senior military authority in NATO is a military committee composed of a chief of staff or special delegate of each member nation.

The standing group, composed of representatives of the Chiefs of Staff of the United Kingdom and the United States, is the executive agency of the military committee.

NATO is divided into three military commands and a regional planning group. The command that concerns air defense is Allied Command Europe, which covers the land area extending from the North Cape of Norway to North Africa and from the Atlantic to the eastern border of Turkey.

Of particular interest in Allied Command Europe is Allied Forces, Central Europe, extending from the southern boundary of Denmark to the northern boundary of Italy. Allied Forces, Central Europe, has responsibility for air defense of this area and has divided the area by a line running southwest-northeast through the approximate center. The responsibility for air defense of the northern portion is assigned to the 2d Allied Tactical Air Force (2 ATAF), while responsibility for air defense of the southern portion is assigned to the 4th Allied Tactical Air Force (4 ATAF) (fig 20).

The commander of 4 ATAF exercises operational control of all assigned air defense artillery forces through the sector operations center (SOC). Tactical control of surface-to-air guided missile units in the US area of responsibility is exercised by the SOC sector controller. The SOC is a NATO installation, combining facilities of the battle staff, an Air Force control and reporting center, and an Army missile control center (i.e., Army air defense command post). Missile control centers, tactical headquarters of the Army air defense commanders, supervise the operations of subordinate air defense artillery units. The battle staff, supervised by the sector controller, supervises overall air defense operations. The master controller coordinates activities between the missile control center and the control and reporting center. Operational procedures of US Army air defense artillery units in NATO are similar to those of air defense artillery units in the United States.

AIR DEFENSE IN PACIFIC AREA

In the Pacific area, US Army air defense artillery units are deployed in Korea, Okinawa, and Vietnam. The Commanding General, US Army, Pacific(USARPAC), commands, trains, and administers the Army units. Operational control of all Pacific area air defense forces is vested in Pacific Air Forces (PACAF) (fig 21).

As an example of how a PACAF air defense sector operates when forces are deployed, the Korean sector is typical (fig 22).

Air defense artillery units in Korea are integrated for operational control into the overall air defense system of the West Pacific North Air Defense Region, a subordinate command of PACAF. The Commanding General, 5th US Air Force, is the West Pacific North Air Defense Region commander. The region is divided into four specific actively manned air defense sectors, one of which is the Korea air defense sector. The 314th Air Division is responsible for air defense of the Korea air defense sector and operates a tactical air controlcenter(TACC) that coordinates the activities of two control and reporting centers/Army air defense command posts (fig 23). The control and reporting center (CRC) in each subsector coordinates the activities of air defense means in its area of responsibility. Operational procedures of air defense artillery units in Korea are similar to those of units in the United States.

Figure 19. NORAD operational structure.
Figure 20. NORAD organization.

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Figure 21. Pacific air defense organization.
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Figure 22. Pacific Air Forces operational control structure.
Figure 23. Concept of PACAF air defense operations.

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AIR DEFENSE IN THE FIELD ARMY

In World War II and in the Korean conflict, the ground-gaining arms could almost always be assured of being able to operate without serious hindrance from enemy air. This basic assumption that our airpower could and would always provide us with air superiority and hence freedom of action on the ground in any future action has generally gone unquestioned, and has been perpetuated in the scenarios of almost every major exercise, command post exercise (CPX), Army training test (ATT), or other field problems.

This assumption is no longer valid. A technically and tactically competent enemy can gain and maintain air superiority for at least a limited time over areas of his own choosing. This problem is greatly simplified if he has adequate conventional gun and surface-to-air missile defenses in being so that he is relatively free to shift his fighter aircraft, even for short times, from basically defensive to offensive operations.

Joint Chiefs of Staff Pub. 8, Doctrine for Air Defense from Oversea Land Areas, May 1964, serves as common doctrine and prescribes the establishment of a coordinated and integrated air defense system under a single commander. This document states that air defense forces must be organized, equipped, trained, and, when possible, positioned and alerted prior to hostilities. An air defense cannot be adequately improvised. Constant surveillance must be maintained to insure timely response of air defense forces and concurrent warning to the offensive forces of the command. The enemy air threat must be considered as an entity and countered by a strategy based upon unity of effort. Tne hostile threat and targets to be defended are the points of departure for all air defense planning and the basis on which air defense requirements must be computed.

Within an oversea unified command, subordinate unified command, or joint task force, the commander will assign overall responsibility for air defense to a single commander. Normally, this will be the Air Force component commander. Representation from the other service components involved will he provided, as appropriate, to the air defense commander's headquarters. The mission of the area air defense commander will be to coordinate and integrate the entire air defense effort within the unified command. Subject to the authority of the unified commander, he will establish broad policies and procedures for the employment of air defense means and the coordination of such means with the operations of other elements within the area. Where a significant portion of the means for air defense is contributed by a service other than that of the area air defense commander, a senior officer should be appointed from that service to serve as deputy to the area air defense commander in air defense matters.

The area air defense commander will establish air defense regions. The number of such regions may vary, depending upon geographical factors and the complexities of the air defense problem. He will appoint regional air defense commanders and designate their areas of responsibility, taking into consideration such factors as the geography of the area, the hostile threat, and the contributions of the services. In a region where a significant portion of the regional air defense means consists of air defense weapon systems of another service, a senior officer of that service should be appointed to serve as deputy in air defense matters to the regional air defense commander. Service staff representation will be assigned, as appropriate, to the regional air defense activities. The regional air defense commander will be fully responsible for, and will have full authority in, the air defense of his region. However, he will normally delegate authority to the field army commander(s) for control and operational employment of Army air defense artillery means within the field army area.

Coordination of the employment of all air defense means withm the field army is normally accomplished in the tactical operations centers at field army(FATOC), corps (CTOC), and division (DTOC) levels (fig 24). The tactical operations center is an integrated staff facility where representatives of the special and general staff sections are grouped to assist the commander in exercising control of current tactical operations. Air defense is represented in the TOC by the airspace coordination element (ACE) composed of both ADA and Army aviation personnel. The senior ADA unit headquarters provides personnel and equipment to the ACE of the force to which it is organic, assigned, or attached. Only the divisional Chaparral/Vulcan battalion TOE provides organic resources for this purpose. Other ADA units obtain ACE personnel and equipment as provided in TOE 44-510 or from unit resources. The ACE has three basic functions: coordination of AD operations with other tactical and tactical support operations, coordination of airspace utilization by Army forces, and coordination of Army aviation operations.

Joint service coordination is accomplished by means of liaison sections (fig 25). The air defense artillery brigade establishes liaison with the Air Force at the tactical air control center and at the control and reporting center. Air defense artillery groups, if assigned or attached to a corps, would be expected to establish liaison with a control and reporting post. The divisional Chaparral/Vulcan (C/V) battalion liaison section is provided for liaison with the air defense artillery group or Hawk battalion, whichever is appropriate. This team is a link between the organic divisional air defense capability and the corps of Army area air defense capability for coordination of air defense plans. Liaison either through personnel or via communications should be established between the C/V battalion and the forward area control post (FACP) of the Air Force whenever possible.

Coordination may be accomplished by collocation of the AADCP's with the appropriate Air Force installation or by utilizing established communications networks used by liaison teams. In theaters where Air Force and Army air defense organizations are equipped with compatible electronic command and control systems, coordination will he further improved by having the systems operationally connected.

Figure 24. Organization of type field army.
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Current oversea deployments vary from area to area. The principal differences are generated by the need to tailor the defense to the local conditions. The local conditions are included in a consideration of the threat and geographical factors.

To meet the requirement for rapid response to hostile air activity, communications are paramount. The Army, realizing this need for faster, more positive fire distribution of surface-to-air missiles in the field army, developed The AN/MSG-4 (Missile Monitor) command, control, and coordination system. This system may be employed for centralized or decentralized control as directed by the Army air defense commander.

Coordinated air defense effort is a requirement, not only within a field army but between the field army and tactical air force. To fulfill this responsibility, the Army air defense commander normally establishes liaison with the tactical air force. This liaison may be accomplished by collocating the AADCP of various air defense artillery commands with the functional counterpart of the tactical air force or by liaison between these elements. Figure 25 graphically depicts a typical solution of the liaison requirement. Liaison expedites the flow of early warning and identification information, two vital elements of data for any air defense. Both the control and reporting center and control and reporting post can provide early warning information to air defense artillery units, and the control and reporting center can provide target identification information.

Figure 25. Field army ADA command, coordination, and liaison.
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AIR DEFENSE ARTILLERY MAINTENANCE

The tactical and operational requirements of current and future air defense artillery systems demand employment of skilled technicians and adequate test equipment To provide responsive maintenance support to the Army air defense commander. Preventive maintenance must be efficiently scheduled and malfunctions rapidly corrected. Maintenance management is the responsibility of every commander and includes motivation, organization, accurate records and reports, and training.

The commander of an air defense artillery unit must have the capability of maintaining a high degree of operational readiness around the clock, in peacetime as well as in combat, and in the United States as well as overseas. He requires technicians who are system diagnosticians, supported by repairmen with a capability for repair of defective assemblies and subassemblies. Emphasis must be in the direction of performing tests, maintenance, and repairs as close to the point of failure as practical. Support personnel organic to air defense artillery units and organizations provide the commander a maintenance capability commensurate with his responsibility. In this light, the principal maintenance functions (organizational and direct support) are immediately responsive to the operational requirements of the system.

The organizational maintenance technician is concerned primarily with system analysis. He has a thorough understanding of electronic theory, the practical application of this theory, and the functions of all components within his area of responsibility. He supervises or performs preventive maintenance and verifies system operational readiness. To reduce repair time and minimize travel on the battlefield, the organizational maintenance technician is trained and must be permitted to perform maintenance to the highest practical level under combat operational conditions.

Timely reports must be made of conditions that adversely affect the maintenance effort. Examples of these conditions are shortages of qualified personnel, equipment, and repair parts; improper scheduling of training; and assignment of missions which impair maintenance of equipment. Commanders must insure that reports concerning maintenance support of their equipment are accurate and reflect the operational readiness of their unit. Analysis of these reports aids in determination of total support requirements.

In short, an effective maintenance program is of the utmost importance in air defense artillery units. Air defense commanders must apply techniques of maintenance management which will insure operating equipment to meet operational readiness requirements. The best in air defense, in peacetime or war, is dependent on efficient maintenance.

ELECTRONIC WARFARE

GENERAL

Electronic warfare (EW) is military action involving the use of electromagnetic energy to determine, exploit, reduce, or prevent hostile use of the electromagnetic spectrum and the retention of friendly use of the electromagnetic spectrum. As such, EW must be considered an integral part of the military operationit supports. Both sides will use all aspects of electronic warfare. From the air defense artilleryman's point of view, electronic warfare consists of the enemy's attempts to degrade ADA electronic equipment capabilities and ADA efforts to counter that degradation. The latter is accomplished by:

  1. providing friendly forces with information about electronic equipment and tactics being used by the enemy, particularly those which involve the use of electromagnetic radiation; and
  2. insuring optimum use of our air defense artillery in the face of enemy electronic countermeasures (ECM) through use of electronic counter- countermeasure s (ECCM).
Electronic warfare is divided into three categories: electronic warfare support measures(EWSM), electronic countermeasures, and electronic counter-countermeasures.

ELECTRONIC WARFARE SUPPORT MEASURES

Electronic warfare support measures is that category of EW involving actions taken to search for, intercept, locate, record, and analyze radiated electromagnetic energy for the purpose of exploiting such radiations in support of military operations. The analysis of intercepted radar and data link signals can provide a comprehensive picture of the electronic capabilities of opposing forces. From these signals a fairly accurate estimate can be made of the number, types, and locabons of emitters in the opposing force. The data on number, types, and locations of opposing emitters, coupled with intelligence from other sources, provide a reasonably accurate assessmentof the size, disposition, and possible intent of the opposing forces. With this information available, the tactical commander can better determine the EW equipment that is needed and the tactics that should be used to make his operation most effective. Some types of information secured by EWSM and the means used to obtain this information are listed below.

In EW the reconnoitering units are commonly called ferrets, and all activity pertaining to the accumulation of enemy electronic information is referred to as ferret operations. Ferret personnel are highly skilled in the operation of specialized radar detection equipment.

ELECTRONIC COUNTER MEASURES

Electronic countermeasures is that subdivision of electronic warfare involving actions taken to prevent or reduce an enemy's effective use of the electromagnetic spectrum. ECM is used by the enemy to introduce signals directly into other radar receivers. Its object is to impair the use of electromagnetic energy or prohibit accurate interpretation of the information on the radar indicators of other air defense missile systems. ECM does this through production of obscuring, confusing, or connicting patterns on these indicators.

Electronic countermeasures are classified either as jamming or deception depending on the purpose and application of the countermeasure signal. Jamming ECM and deception ECM can he either transmitted or reflected.

Deception is the deliberate radiation, reradiation, alteration, or reflection of electro-magnetic energy in a manner intended to mislead an enemy in the interpretation or use of information received by his electronic systems. Deception against air defense artillery radars is intended to deceive the radar operator or the tracking system of a radar set. To be effective the deception signal must be interpreted as a real target or signal. It must confuse or delay the radar operator or cause unacceptable inaccuracies in the radar system. The deception signal can be produced by transmitters (transmitted deception) or by reflectors (reflected deception).

Transmitted deception is produced by special radiofrequency transmitters. These transmitters produce signals which can cause false or inaccurate echoes, or a combination of both. These are presented to a radar set to confuse the operator or the automatic electronic control system. The signals from the deception transmitters may be deceptive strobe lines or targets ranging from a single target of inaccurate range to targets representing a large formation of planes or targets scattered all over the indicator to make it difficult to discern the true target. There are four primary types of transmitted deception. Three are known as "track breakers" because they are used against tracking radars in an effort to break radar lock-on. The fourth type is used against acquisition radars.

Reflected deception is produced by objects capable of reflecting electromagnetic energy so that the return echoes will present false or inaccurate information to the radar operator or electronic control circuits. Because these are reflective devices, they are used only to counter radar and are commonly referred to as confusion reflectors. The most commonly used confusion reflectors are chaff, rope, corner reflectors, and decoys.

Jamming is produced by two methods. The jamming signals may be produced by an active transmitter, or they may be the result of reflecting or reradiating a radar transmission. Both types of jamming are used to accomplish the same purpose: to screen the video return of the attacking aircraft.

Transmitted jamming is used to overcome real target returns by the use of brute force techniques. It is designed to saturate or block victim receivers, display units, and automatic tracking circuits. A jamming signal will, in some cases, be transmitted at the same frequency as that of a specific radar and will be intended to jam that radar. Other types of jamming signals will cover the frequencies of many radars simultaneously. Still other jamming signals will sweep through a broad band of frequencies at such fast rates that, for all practical purposes, the entire frequency band is jammed continuously. There are many variations of transmission jamming and many types of transmission jamming equipment. However, the general purpose of all types of jamming and jammers is to inject into a radar set a signal of such characteristics and intensity that it will seriously impair the effectiveness of radar operation or will render a radar set temporarily useless.

The most common means of accomplishing reflected jamming is through the use of chaff in large quantities. It reflects the pulses from the radar transmitter back to the radar where they are picked up and processed by the receiver. These echoes from the large quantities of chaff cause indications on the radar scope that obscure actual target echoes. Reflected jamming may also be used with transmitted jamming to increase the intensity of the jamming signals displayed on the radar indicator.

ELECTRONIC COUNTER-COUNTERMEASURES

The means of reducing the effectiveness of enemy ECM are known as electronic countercountermeasures. ECCM, in a broad sense, includes alloperations, equipment circuits, and training designed either to avoid ECM or to improve the operation of electronic equipment under ECM conditions. Because of tremendous strides in the development of ECM devices, it has become necessary to provide the radar operator with controls, additional equipment, and special circuits to aid operation in an ECM environment. Each control or circuit is designed to be effective against a specific kind of ECM, thus establishing a requirement for an extensive training program for radar operators and supervisors. The operator must recognize the effects of each type of ECM and know which ECCM control or technique is designed to be most effective in combating the ECM. If his ECCM controls and techniques are to be effective, the operator must have a properly functioning radar system. He must also have the ability to distinguish between accidental interference, set malfunction, and deliberate jamming. Efforts to reduce the effects of ECM, to avoid ECM, or to improve operations in an ECM environment are generally directed toward four areas: increased power, frequency diversity, special circuits, and operator training. Of the four, operator training is the most important. For radars to operate effectively in an ECM environment, the operator must expect ECM, recognize and identify ECM, report ECM, and take appropriate ECCM action.

IDENTIFICATION, FRIEND OR FOE

Identification of airborne objects presents a major problem to all air defense units. To prevent destruction of friendly aircraft, a positive means of identification must be provided. This need was initially met by development of the Mark III identification, friend or foe (IFF), system. This system, used with ground station radars during World War II, assisted in the identification of aircraft, but limitations of the system caused its use to be discontinued at the end of the war. Research was started to develop an identification system to satisfy the needs of all services. The Mark XIFF system was the result.

The Mark X IFF system is composed of two groups of equipment. One, the interrogatorresponder, is located with ground radars and the other, the transponder, is located aboard friendly aircraft. The interrogator-responder is installed at the ground station and depends on a parent radar for a synchronizing trigger, an ac power input, and a plan position indicator (PPI) to display IFF video. Its major components include a coder control (modes i, 2, and 3), receiver-transmitter, and antenna. The interrogator- responder antenna is unidirectional. Because the radar antenna is also unidirectional, the two antennas must be synchronized for azimuth resolution. (This causes IFF video to be portrayed on the PPI at the same azimuth as the radar video of the interrogated target.) The airborne transponder is independent of any radar that might be located in the aircraft; however, it requires power from a source in the aircraft. The unit consists of a receiver-transmitter and antenna. The antenna is omnidirectional; thus, it can receive and transmit in any direction.

The sequence of operation (fig 26) for Mark X equipment is the same for Nike Hercules and Hawk batteries; battalion operation centrals; command, control, and coordination systems; and AADCP's.When target video appears on the PPI, the acquisition radar operator or tactical control assistant (Hawk battery) places the interrogator-responder in operation by turning on the challenge switch. (The acquisition radar operator or tactical control assistant will determine which IFF modeis to be interrogated.) This causes a pair of radiofrequency (RF) pulses to be transmitted from the IFF antenna at the same azimuth as the radar pulse. These RF pulses will have an interpulse spacing, from leading edge to leading edge, of 3, 5, or B microseconds, depending on which mode is being interrogated (mode 1, 3 microseconds; mode 2, 5 microseconds; and mode 3, 8 microseconds). The transponder receives the RF pulse-pairs and amplifies the challenge signal (both RF pulses must be present because one pulse does not constitute a valid challenge). Upon receiving a valid challenge, the transponder will then transmit its identification signal. The reply is received and amplified in the interrogator-responder 'eceiver. The output of the receiver through the decoder is sent to or four arcs at a range greater than the the PPIwhere it will be displayed as one, two, interrogated aircraft but at the same azimuth (one are is the valid response for a mode 1, 2, or 3 challenge, two arcs constitute a valid response in modes 1 and 3 for an identification of position (IF) reply, and four arcs indicate that the aircraft has declared an emergency).

Figure 26. Identification, friend or foe (IFF).
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The Mark X IFF equipment used in conjunction with air defense artillery radars includes a selective identification feature (SIF) which enables the IFF equipment to receive 32 codes in mode 1 responses and 64 codes each in mode 2 and mode 3 responses. The 160 possible codes of the Mark X IFF/SIF system enabled the establishment of a more positive identification system. When the selective identification feature (SIF) of the Mark X IFF system is used, correct responses by the interrogated aircraft will be displayed as one are, except for IP, at a range greater than the interrogated aircraft hut at the same azimuth. Should the aircraft declare an emergency, the SIF reply would appear on the PPI as four arcs.

Currently under development is a new family of IFF equipment known as the Mark XII system. The Mark XII IFF includes AN/TPX-46 and AN/TPX-50 interrogator sets which incorporate the features of Mark X with two additional modes, C and 4. The AN/TPX-46 with Mark X modes 1, 2, and 3/A, and Mark XII IFF capability in mode 4, will replace the AN/TPX-26 and AN/TPX-27 Mark X IFF/SIF now in use in US Army air defense installations. The AN/TPX-50 with Mark X modes 1, 2, and 3/A and Mark XII mode 4 capability will be mounted on the forward area alerting radar associated with Chaparral/Vulcan weapon systems The AN/TPX-45 with modes 1, 2, and 3/A capability is used with self-propelled Hawk.

At present, four modes of interrogation between military aircraft and military and civil ground stations are used. Modes 1 and 2 are assignedto and used bythe military. Mode 3/A is assigned to both military and civilian aviation for common air traffic control. Modes 2 and 3/A are currently limited in application due to the relatively few codes provided. In the new sets, modes 2 and 3/A will be expanded to 4, 096 code selections and, under the Mark XIIconcept, an additional mode 4 will be provided. Mode C (altitude reporting) is provided for Air Force and civil aviation but is not currently planned for Army aircraft.

The operational concept of the Mark XII identification, friend or foe, system is similar to and compatible with the Mark X IFF/SIF. Both are really identification-of-friend systems. An aircraft not identified as a friend is an unknown, possibly a foe. The Mark XII mode 4 cryptosecure feature provides the most positive and reliable identification of friendly aircraft to date.

AIR DEFENSE ARTILLERY COMMUNICATIONS
The vital link between weapon systems and command, control, and coordination facilities of air defense artillery is communications. The supersonic nature of the air threat dictates that air defense artillery communications be rapid, reliable, and redundant to insure maximum effectiveness on a continuous basis.

Within NORAD, air defense artillery communications in a fixed environment is provided by a combination of means to include both the sophisticated facilities of the Defense Communications Agency (DCA) and leased commercial facilities. The Defense Communications System (DCS) automatic voice network (AUTOVON) has been extended throughout the NORAD organization. Leased cable, microwave radio, and other means provide redundancy to enhance communications sunrivability while insuring reliability under adverse conditions.

Presently, ARADCOM defenses are supported by either peripheral microwave or land line service. The North American Air Defense Objective Plan (NADOP) authorizes replacement of existing landline systems with peripheral systems (microwave or other) providing dedicated air defense communications between the Army air defense command post (AADCP), alternate command post(ALCOP), and all missile fire units. Landline defenses will he aflorded the same circuit capability as microwave defenses until such time as peripheral communications systems are installed. VHF radio will be retained as operations control backup.

Communications for air defense artillery units (Hawk and Nike Hercules) in an oversea or mobile air defense environment are furnished by both organic and nonorganic equipment. The primary means of communication for Hawk and Nike Hercules units is a very high frequency/ultrahigh frequency (VHF/UHF) radio relay system. This primary system of VHF/UHF multichannel equipment supports the electronic command, control, and coordina tion systems deployed with these field units. It is capable of transmitting both digital data and voice information.

Figure 27. Radio terminal set AN/TRC-145
Figure 28. Radio relay set AN/TRC-113.

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The basic equipment used to establish primary communications is the radio terminal set AN/TRC-145 (fiy 27). This set is a package consisting of two AN/GRC-103 radio receivertransmitters and two TD-660 telephone multiplex terminals. It provides a dual 6/12-channel duplex capabilitg with a rated range of 40-48 kilometers between stations, provided electrical line of sight is maintained. The AN/TRC-145 can be used as a dual terminal or relay set, or as both simultaneously.

Should it be necessary to provide communications beyond the line of sight capability or range of the AN/TRC-145, radio relay set AN/TRC-113 (fig 28) could be used to extend the circuit. The AN/TRC-113 consists of three AN/GRC-103 radio receiver-transmitters, two of which are necessary for providing relay operation and the third being used solely as a standby component for increased reliability.

This equipment is scheduled to become an addition to ADA TOE and will be fielded as they become available. Older equipment, consisting of the AN/TRC- 24 radio receiver-transmitter and the AN/TCC-7 telephone multiplex terminal, will continue to be used until the new equipment is issued.

Nike Hercules and Hawk units are issued the following organic radios to provide backup to the primary communications system.

The AN/GRC-106 (fig 29), an amplitude-modulated (AM), single sideband (SSB) radio set, is used in tactical nets. Designed for mobile or fixed use, it is capable of providing communication over a distance of 50 miles when using the organic whip antenna.

Figure 29. Radio set AN/GRC-106.
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The AN/GRC-122 is a shelter-housed transportable radioteletypemiter set which uses the AN/GRC-106 as its major basic component. The AN/GRC-122 is authorized for air defense artillery battalions primarily to provide teletypewriter communication with higher headquarters.

The AN/GRC-26 is a longrange AM radio used at group and brigade levels.

The TOE for all air defense artillery echelons, brigade to battery, include new type communications equipment. In voice command nets, the new AN/VRC-12 family of frequencymodulated (FM) radios has been issued. The basic receiver transmitter of the AN/VRC-12 family issued to air defense artillery units is the RT 524 which is shown in figure 30 as the major component of the AN/VRC-46. The AN/VRC-47 (fig 31) is a basic FM receivertransmitter with an auxiliary receiver and associated equipment, and the AN/VRC-49.

Figure 30. Radio set AN/VRC-46, Figure 31. Radio set AN/VRC-47
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consists of two of the basic receiver-transmitters with a retransmission unit and associated equipment. These small, rugged radio sets possess a range capability of 32 kilometers using a whip antenna. Channel capacity is increased to 920 channels, making it capable of netting with infantry, armor, or field artillery units.

Technical advances in weapon systems and advanced concepts of deployment result in ever-increasing demands within the field of communications. Fortunately, improvements in communications equipment design have met this challenge, and the end product is a new series of radios with improved capabilities as well as reduced size, weight, and power requirements .

The man-packed AN/PRC-25 radio, another of the improved radios, is a forward area radio set to replace the AN/PRC-H, -9, and -10 radios. Its use by Nike Hercules batteries will improve unit security control. This basic set is also to be built as a vehicle-mounted version (AN/VRC-53) or as a convertible man-packed /vehiclemounted version (AN/GRC-125). The normal range is 8 kilometers. Communications provided for air defense artillery forward area weapons (FAW) include all means necessary to transmit information, intelligence, commands, and means to establish liaison with other units. Communications means available to these units include radio, wire, and messenger. TOE radios (AN/CRC-106, AN/GRC-46, and the VRC-12 family) discussed above are the primary means of communications in the FAW units. Wire and messenger are used as a backup to these organic radios.

The challenge presented to air defense artillery communications as a result of technical advances in command, control, and coordination systems and modern weapons has been more than adequately satisfied by aggressive research and development within the field of communications equipment. The new, compact, longer range communications equipment is being issued to all echelons of air defense artillery to provide an even greater capability to accomplish the latter portion of the artillery axiom--move, shoot, and communicate.


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Updated August 7, 1998