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Develop a Joint Data Link
“That’s a pretty good data link you’ve got there—want to see mine?” When it comes to communicating, standardization is everything. It does not preclude the individual services from tailoring their data links to individual needs, but it does mean that the services—all of them—must agree on a certain minimum level when designing the systems they will use to talk to each other. Some experienced users offer their insight.
Jeffrey McManus
In his classic work, On War, Carl Von Clausewitz discusses the concept of friction on the battlefield: “In war everything can be very simple, but the simplest thing is usually difficult.”1 This is especially true for the battlefield commander, who requires up-to-date information to control and direct his forces effectively in accomplishing his mission.
Uncertainty—defined as a lack of situational awareness—is one of the largest contributing factors to battlefield friction. Effective communication between military forces lessens uncertainty and thereby decreases battlefield friction. Today, the efficient flow of information on high-volume electronic data links is based upon two primary principles:
► Connectivity is the physical ability for combat systems to exchange information, including items such as frequencies used, encryption schemes, message formats, and types of information for exchange.
► Commonality relates to the language and terminology of different services and systems—the ability to understand the messages being sent and received.
Given the new emphasis on joint warfare for the military services (as defined and required by the Goldwater-Nichols Act of 1986), the ability to integrate multiservice weapon systems and coordinate air defenses is critical to future military success. To date, however, there is no effective joint-service data link able to integrate our air-defense forces efficiently. In fact, a joint data link is still fictional.
Data links are used either internally or externally by electronic systems and play an integral role in today’s air defense combat systems. The air-defense process is focused around three primary functional areas:
► The detection process should allow all sensors in the air- defense network to be integrated, forming a sensor grid where each sensor’s detections are reported into a combined air-defense picture.
► The control process should allow this combined air picture to be correlated and controlled by passing a combined and clear air picture throughout the network, providing situational awareness to the battlefield commander and to all participants in the network.
► The engage process should allow the commander to manage the air defense effectively and efficiently by enabling transmission of commands to all the integrated weapon systems.
The evolution of each of the military service’s multiple tactical data information links (TADILs) in air defense has varied depending upon past service roles and missions. The more prominent of today’s data links include:
► TADIL-A: also called Link-11. the primary means for data exchange for the Navy and used by the Air Force and Marine Corps
► TADIL-B: also called Link-1 IB, similar to Link-11, but used by the Army and Marine Corps for ground unit point-to-point data exchange
► TADIL-C: also called Link-4A, a two-way data link for fighter combat-air-patrol aircraft command and control (C2)
► TADIL-J: also called the Joint Tactical Information Distribution System (JTIDS) or Link-16, planned as the joint replacement to TADIL-A and others for the Army, Navy, Air Force, and Marine Corps
► TADIL-I: the Interim JTIDS Message Specification (IJMS) data link, which is used by the first generation (Class 1) JTIDS terminals and primarily by the Air Force
► Patriot Data Information Link (PADIL): used for data exchange between Army Patriot surface-to-air-missile batteries and Army C2 nodes
► Army Tactical Data Link (ATDL): used for data exchange between Army and Marine Corps Hawk surface-to-air-missile batteries and C2 nodes
These data links may serve their particular users well but are extremely difficult to integrate in a joint environment. To illustrate this point, one current Joint Test Force refers to this multiple data link environment as “TADIL BABEL.”2
The evolution of the services’ TADILs resulted from their varied roles and missions. The Air Force and Army systems were designed to defend primarily the Fulda Gap and North Atlantic Treaty Organization (NATO) forces in Central Europe. This air-defense network was designed around the Air Force’s E-3 Sentry Airborne Warning Air Control System (AWACS) aircraft or the ground-based Control and Reporting Center modular control equipment system. These systems integrate air- and ground-based surveillance sensors, C2 nodes, fighter and attack aircraft, and surface-to-air-missile systems. Air Force systems provide the C2, with Army surface-to-air missiles, giving ground- based missile-defense support with Patriot and Hawk via an Army Information and Coordination Central.
Marine Corps air defense has been designed around the primary Marine mission of amphibious operations. Given its close relationship with the Navy and similar system and equipment functionality with the Army and Air Force, the Marine Corps demonstrates the foremost ability by remaining compatible with most TADIL architectures. Marine Corps air defense is designed to be self-contained. Unlike the Army, the Marine Corps maintains an integrated joint C2 capability with their Tactical Air Operations Center modular control equipment system, which combines ground-based sensors (AN/TPS-59 and AN/TPS-63) for surveillance and tracking, fighter and attack aircraft for combat ground support, and Hawk and short-range air defense surface-to-air missiles for air defense.
Navy air defense has been designed as a defense-in-depth, with a blue-water, open-ocean focus. This defense has been centered traditionally around an aircraft carrier battle group using the E-2C Hawkeye airborne platform or the modern Aegis weapon system, with its AN/SPY-1 phased-array radar for
The ability to coordinate air defenses in joint warfare is critical for future military success— but this AWACS crew lacks an effective joint- service data link to get the job done.
surveillance and C2. This air-defense doctrine has used fighter and attack aircraft and Tomahawk missiles for the outer-air battle and strike; long-range missiles such as Standard Missile-2 for area defense; and close-in weapon systems, including Sea Sparrow missiles and Phalanx guns, for point defense. Navy systems integrate well when operating with other Navy units, but the Navy has had little operating experience in a joint, integrated air-defense network.
Operation Desert Storm was the first large-scale test of the new joint focus. Joint air defense was first coordinated by onscene Navy units, but as Air Force, Army, and Marine Corps forces arrived in theater, the Joint Forces Air Component Commander (JFACC) was set up ashore in Saudi Arabia. Problems caused by the services’ data link incompatibilities erected a digital data link wall along the coast of the Persian Gulf. The Air Force controlled the joint Air Force/Army/Marine air- defense network over Saudi Arabia and Kuwait; the Navy maintained air-defense control over the Persian Gulf; Marine Corps tactical air operations center (TAOC) units operating near the Gulf provided a partial and intermediate data-forwarding capability between the land and sea data links.
Several enterprising Navy units attempted to reconfigure their data link equipment to receive both the Navy and Air Force air defense data links simultaneously. At the time, this hot-wired configuration appeared to work, but detailed data analysis later showed that it only allowed a small percentage of the Air Force data link information through, while greatly reducing these reconfigured Navy units’ connectivity in the Navy data link. While this demonstrated the ingenuity and initiative of our military personnel who were striving to obtain much needed air-defense data, they were forced to modify their weapon systems to support their mission adequately.
When one points out the deficiencies of the current data link situation, the usual response is; “What about JTIDS?” JTIDS is a jam-resistant, secure, line-of-sight data-link and communications system that is being implemented in two stages.
Class 1 JTIDS is the interim data link that uses the interim message format IJMS (or TADIL-I), which is currently used to provide data-link capability to C2 systems such as the Air Force’s Control and Reporting Center and AW ACS aircraft, and the Army’s Information and Coordination Central.
The plan for JTIDS is to incorporate all of the major com- mand-and-control and weapon systems of the Army, Navy, Air Force, and Marine Corps into a true joint data link. Full JTIDS- implemented systems will use the Class 2 terminals. However, the evidence to date—including the length of time spent in ongoing implementation—suggests a serious lack of planning, emphasis, and support by the military services for JTIDS.
The Air Force has complied with the first step toward JTIDS capability by implementing Class 1 JTIDS, or IJMS, in the E-3 Sentry AW ACS aircraft and the Control and Reporting Center ground-based system. In addition, the Air Force is testing initial production JTIDS Class 2 terminals in a squadron of F-15 Eagle fighters to evaluate the operational benefits of data- link-capable aircraft. However, Air Force intelligence and identification aircraft use TADIL-A and other intelligence data links, not IJMS. Full integration of JTIDS by the Air Force in the near future does not appear likely.
The Army has no direct JTIDS-capable systems. To participate on an IJMS data link, Army units require either an Air Force Control and Reporting Center system or a Marine TAOC system using an adaptable surface interface terminal (ASIT) translator. A program under Army development is the joint TADIL-A Distribution System (JTADS), which translates TADIL-A to TADIL-B or ATDL; however, it is unknown whether the Army has plans to implement JTIDS or a direct JTIDS translator in its Information and Coordination Central system. In addition, the Army has no capable C2 system able to command “joint” air defense C2. The Army Battalion Tactical Operation Center was designed for battlefield situational awareness, not C2, and the Information Coordination Central does not have the computer capability or manpower to control more than Patriot and Hawk surface-to-air-missile batteries.
The Marine Corps TAOC systems can participate on an IJMS data link if an ASIT translator is used. The Shelterized JTIDS System can also provide the TAOC with both IJMS and full JTIDS data-link capability. The Marine Corps appears to be the most flexible when it comes to data links. Marine Corps TAOC units also have a great deal of operational experience through working and training with the Navy, Army, and Air Force.
The Navy’s Carl Vinson (CVN-70) carrier battle group (including one Aegis cruiser) is the first Class 2 JTIDS-capable battle group. It experienced a multitude of problems with the JTIDS terminal equipment during the pre-deployment training period, but further study will reveal whether this “JTIDS battle group” will be used in the future. The JTIDS situation within the Navy today is not surprising, considering Navy data link policy with TADIL-A, the primary naval data link. For example, although the 27th and final Aegis cruiser, the Port Royal (CG-73), is now operational, none of those ships are in full compliance or certified with Navy TADIL-A standards. However, it is not clear whether overall TADIL-A compliance by the Aegis program is needed, since the Navy itself is not in full compliance with joint TADIL-A standards.
In addition to JTIDS implementation, what about the integration of other current and planned data links? What about the planned cooperative engagement capability link? What about intelligence data links, such as the Tactical Information Broadcast System, tactical receive equipment, or tactical receive equipment application? Is anyone looking at how these will be integrated jointly, or will they too just add another dimension to TADIL BABEL?
Joint data link standards must be identified and must meet current system requirements for all four military services. One data link, however, will not provide all things to all systems; therefore, the joint data link standards should define a minimum level required for all systems. A multitude of other data link
The USS Carl Vinson (CVN-70) carrier battle group had problems with its JTIDS terminals during work-ups, not surprising given the service’s data-link policy.
'Carl von Clausewitz, On War (Princeton NJ: Princeton University Press, 1984), edited and translated by Michael Howard and Peter Paret,
messages could also be defined to be used by a smaller set of systems on the data link, or systems could be designed to tune in to only the data link messages necessary for their operations. However, these additional messages must not adversely impact the basic ability for all systems to participate with the minimum- defined standard set. In addition, these standards must be
flexible and able to grow with the advent of new missions and new technologies, to include: theater air defense, tactical-ballistic-missile defense, longer-ranging strike, intelligence information, and littoral amphibious operations.
Given the joint and littoral emphasis, each service should also develop at least one system capable of providing full joint air defense C2, which would allow each service the capability to “take the lead” in any contingency, with smooth transitions of command.
All services and systems must comply with the minimum standards. These requirements should be tied to each air-defense system’s milestones and/or funding, and the service’s combat system program offices must be held accountable to ensure that each system supports the joint-warfare environment. In addition, a much higher emphasis must be placed on joint service training. Joint training will assist each service in learning and familiarization with other services’ systems and capabilities and in creating and establishing joint procedures. Only when the services train and practice together will they be able to fight together effectively.
An effective integrated digital data link is essential for joint air defense success. Full integration of the joint data link picture will lessen battlefield uncertainty and greatly reduce the fog of war.
pp. 117-121.
:“TADIL BABEL” is a term (referring to Genesis 11:1-9) coined by the Joint Air Defense Operations/Joint Engagement Zone, Joint Test Force, located at Eglin Air Force Base, Florida, that is tasked to study new joint engagement procedures.
Jeffrey McManus is an Aegis Systems Analyst at the Naval Surface Warfare Center, Dahlgren Division.
We Need Joint Data Fusion Centers
Lieutenant Donald D. Gabrielson, U.S. Navy
Recent world events have underscored a need for interservice cooperation in the pursuit of carrying out U.S. Foreign policy. While each service, in turn, has acknowledged the need to develop ‘Jointness,’ limited measures have been taken at the Fleet and field levels to enhance and promote greater understanding and to allow closer operational ties. One key example is the sharing of tactical information over data links. Each service has developed link systems along separate lines, and although there are cases in which those systems interface directly (most notably, AWACS into Link 11), for the most part each system functions on its own. Integrating different link systems has been included as an afterthought to design, making interoperability difficult at best.
Our current data-link systems do not work acceptably in a joint environment, and they cannot provide reliable data flow across the large operating areas we monitor. They are not flexible enough to maintain a high-quality local picture while attempting connectivity in a difficult environment, because the focus is often shifted to a single participant at the cost of other units that rely on link data for control and survival. Link operators are left to battle among themselves to provide a marginal tactical picture, generating friction and even hostility toward other operators. The real problems lie in the laws of physics, as they relate to the operation of our contemporary systems: We cannot do the job with what we have. A lack of data integration at-the tactical level undermines the goal of jointness.
We must consider options that develop link interoperability at a level that guarantees greater operational closeness in the future: during daily operations around the globe. The recently completed Bottom Up Review highlighted a need for greater joint C4I capabilities. The ongoing development of theater- level enhancements to air-defense systems undoubtedly will increase the need for a large-area tactical-data picture. The data-link systems used today will not support effective tactical employment of long-range surface-to-air missiles. The current J6 initiative, C4I For the Warrior, envisions a worldwide command-and-control network in which every service can share all-source information.
At issue is a lack of joint tactical data sharing, not a lack of ability to gather tactical data. Each service develops its own tactical data picture, and all too often, one service knows the identity or intentions of a radar track, while others struggle to