Tactical Electronic Warfare Aircraft In The Twenty-First Century CSC 1993 SUBJECT AREA - Electronic Warfare (EW) EXECUTIVE SUMMARY Title: TACTICAL ELECTRONIC WARFARE AIRCRAFT IN THE TWENTY-FIRST CENTURY Author: Major R. A. Muegge, Student, United States Marine Corps, Marine Corps Command and Staff College Thesis: There are too many different types of tactical Electronic Warfare (EW) aircraft in the US military. The solution is to phase out the Air Force's EF-111A and replace it with the Navy/Marine Corps' EA-6B. Background: In the aftermath of the Cold War, the proper reduction of military forces and systems is critical. Senator Nunn identified two aircraft that should be considered for consolidation: the EA-6B and the EF-111A. While both the EA-6B and the EF-111A performed admirably during the Gulf War, the EA-6B stood out as the most capable tactical EW aircraft. The EA-6B's ability to shoot the High Speed Anti-Radiation Missile (HARM) made it invaluable. The EA-6B is undergoing the EA-6B Advanced Capabilities (ADVCAP) upgrade that will continue to keep it well ahead of all tactical EW aircraft in the world. The EF-111A upgrade will, at best, make it as capable as the current version of the EA-6B. Recommendation: The EF-111A should be phased out of the US inventory. The EA-6B ADVCAP program should be expanded in order to provide the Air Force with the EA-6B ADVCAP, to replace the loss of the EF-111A. This is a "win-win" proposition for both the Navy/Marine Corps and the Air Force. The US military gets the best tactical EW aircraft at an overall lower cost. TACTICAL ELECTRONIC WARFARE AIRCRAFT IN THE TWENTY-FIRST CENTURY OUTLINE THESIS: There are too many different types of tactical Electronic Warfare (EW) aircraft in the US military. The solution to this problem is to phase out the Air Force's EF-111A and replace it with the Navy/Marine Corps' EA-6B. I. History of Electronic Warfare A. The Beginnings of EW B. History of the EA-6B C. History of the EF-111A II. Capabilities of the Tactical EW aircraft. A. Capabilities of the EA-6B B. Capabilities of the EF-111A III. Gulf War Performance A. Marine Corps EA-6B performance B. Navy EA-6B performance C. EF-111A performance IV. The Problem A. Duplication B. Logistics C. Unity of effort V. The Solution A. Reduced costs B. The EA-6B Advanced Capabilities C. The EF-111A Systems Improvement Program D. Joint interoperability TACTICAL ELECTRONIC WARFARE AIRCRAFT IN THE TWENTY-FIRST CENTURY In 1947 when the Department of Defense came into being, the debate over the roles and missions of the services caused many fierce debates. The Key West agreement, hammered out by the military service chiefs under the leadership of Secretary of Defense James Forrestal in 1948, resolved many problems. One issue that the Key West agreement did not resolve was the prevention and elimination of redundancy and duplication among the military services. The services developed their own version of weapon systems, usually regardless of sister service similar systems. This lack of coordination and joint effort stemmed a great deal from the fight for survival among the services and a "superior service mentality" that presupposed that each service could do a better job of developing their own weapons. This practice led to the production of many weapon systems, especially tactical combat aircraft, that could perform most of the missions required by all the services. Had the services undertaken concept, development, and production efforts together, a number of aircraft would be common to all the service air forces and capable of meeting each service's mission requirements. The joint effort required to produce a satisfactory aircraft must begin in the concept phase and continue throughout the life of the aircraft. Attempts to begin development of common aircraft at any other phase than the concept phase can and often has led to failure. One such example is the F-111 program. James McNamara, then Secretary of Defense, wanted the F-111 to become the Air Force and Navy fighter. The F-111 was under full scale development when this decision was made. Meanwhile, the F-14 was under development by the Navy as its choice for a long range fighter. Because the engineers did not design the F-111 with carrier capability in mind, trying to adapt the F-111 to carrier requirements cost large sums of money and delayed the F-14 program. The F-111 failed carrier suitability tests for a large number of reasons ranging from its size and weight to speed and safety considerations during the approach and landing phase. Had the common fighter issue been addressed as a joint issue from the concept phase, the F-111 might well have succeeded. The specific issue addressed in this paper, stems from Senator Sam Nunn's speech on the Senate floor, on 2 July, 1992. The Senator stated: The Navy's aircraft is the EA-6B, widely considered the best in the world. The Air Force jammer is the EF-111. The Navy has done a better job than has the Air Force of modernizing its jammer fleet. But ironically, even though the Navy has a better overall modernization program, budget pressure within Navy aviation is forcing them to stretch out the EA-6B program, and there have even been indications the program might be canceled. In other words, both services are trying to maintain fleets of stand-off jammers, but budget pressure is seriously limiting their modernization programs. (12:10) Senator Nunn clearly articulated the problem of too many different types of tactical Electronic Warfare (EW) aircraft operating in the US military. The solution is evident and within our grasp: phase out the EF-111A and replace it with the EA-6B. The use of terminology is confusing; further explanation will set the foundation for a better understanding of EW. EW refers to a broad spectrum of measures taken against the enemy's electronic capabilities. The two major subsets of EW are Electronic Countermeasures (ECM) and Electronic Surveillance Measures (ESM). ECM, in a word, is jamming, an active/offensive measure taken against enemy radars and radio communication. ECM and jamming will be used throughout this paper synonymously. ESM, on the other hand, is a passive measure that detects, records, and analyzes the enemy's electronic emissions. The collection of electronic emissions allows the intelligence community to determine what threats exist and where they are located, commonly referred to as the Electronic Order of Battle (EOB). ESM is then used to determine what ECM will defeat the enemy's EW capability. This paper will provide the reader with a historical background of EW and specifically, the development of the EA-6B and the EF-111A. A clear understanding of the nature of the problem and a detailed analysis of both aircraft's capabilities will enable the reader to better understand how logical and appropriate the solution is. A central theme throughout the development of tactical EW aircraft is that they evolved along parallel lines, only crossing paths periodically. This parallel path development of tactical EW aircraft is not an indictment on the way things are done but more an indication of the way things have always been done. A classic example of the result of parallel path development is the EA-6B and the EF-111A. HISTORY OF ELECTRONIC WARFARE The beginnings of EW can be traced at least as far back as 1916 when Fleet Admiral Sir Henry Jackson used EW prior to the Battle of Jutland. Using coastal radio direction finders, Sir Henry determined the direction of movement of the German fleet and maneuvered the British fleet on the basis of this information. This was the first use of what is referred today as ESM. EW became a vital weapon during World War II. Allies used ECM against both the Germans and the Japanese. ECM saved an estimated 450 United States bombers and 4,500 airmen from destruction by radar-controlled German flak. (8:1) In his war memoirs Winston Churchill wrote: During the human struggle between the British and the German Air Forces, between pilot and pilot, between AAA batteries and aircraft, between ruthless bombing and fortitude of the British people, another conflict was going on, step by step, month by month. This was a secret war, whose battles were lost or won unknown to the public, and only with difficulty comprehended, even now, to those outside the small scientific circles concerned. Unless British science had proven superior to German, and unless its strange, sinister resources had been brought to bear in the struggle for survival, we might well have been defeated, and defeated, destroyed. (3:381-382) Churchill was specifically referring to events that happened during the bombing of Britain by the Luftwaffe. He called it "The Wizard War", and its importance made him an ardent supporter of EW. In the early stages of World War II, EW was known as Radio Countermeasures (RCM). The first true jamming of signals occurred in 1940 when the British, using ground based jammers, retransmitted signals on the same frequency that the Germans were transmitting navigation signals to their bombers. This jamming had the affect of rendering the navigational beams useless and in some cases caused the German bombers to mistakenly drop their bombs in the English Channel. The first case of airborne jamming, also the first case of communication jamming, occurred in the Libyan campaign during November 1941. British aircraft jammed German tank radios. Although the EW equipment was crude, it had a dramatically negative affect on the Germans. The US's first use of airborne EW was also its first use of EW. In January 1943, a B-24D, specially configured with ESM equipment, gathered electronic data on a probable Japanese radar site, on the island of Kista, in the Aleutians. These first ESM aircraft were known as "Ferrets". This Ferret confirmed the existence of the radar site, determined its characteristics, and collected radar coverage data that allowed bombers to successfully attack and destroy the radar site. The use of EW in the form of both radar and communication jamming played a critical role in the Normandy invasion. On D-Day, a combination of over 600 airborne, seaborne, and land based jammers blinded the German radars and disrupted the control of German fighters. The success of Operation Overlord owed a great deal to EW in achieving surprise and protecting its vital lines of communication from detection. In 1947, the Air Force established its first Electronic Warfare Officer's course at McGuire AFB, New Jersey with twelve B-29's. This school focused primarily on ESM. In 1961, the school established a permanent residence at Mather AFB, California. The school evolved over the years to embrace the broad aspects of EW, providing training to both Marines and Air Force personnel. In the early fifties, the Strategic Air Command (SAC) organized the 2nd Bomber Wing into an ECM unit for the purpose of developing the best tactics and techniques for employment of existing ECM equipment. The 376th Bomb Wing, later augmented by the 301st Bomb Wing provided SAC with a force of over ninety specially equipped B-47 EW aircraft for both testing and combat. In the latter stages of the Korean War, TB-25Js jammed Anti- Aircraft Artillery (AAA) radars while B-26 bombers sought out and destroyed the AAA batteries. These actions were later said to have kept US air losses from tripling in two years. (14:54) Throughout the fifties and sixties EW took on a much more important role as the Soviet threat continued to grow. Great strides in technology occurred as a result of the arms and space race. Radar guided Surface-to-Air Missiles (SAM) and air-to-air missiles presented a new threat to air power. The means to counter these new threats became essential to the survival of combat aircraft. During the early stages of the Vietnam War, the Navy used the AD-5Q (the "Queer Spad") and the EKA-3B Skywarrier as its EW aircraft. The Marine Corps developed the first tactical EW jet: the EF-10B. Because of the increasing density of the electronic combat environment, military leaders realized that most strike aircraft could not carry all the ECM equipment they needed and still carry a credible bomb load. This led to the realization that the military needed a dedicated tactical EW aircraft. The Air Force developed the first dedicated EW aircraft: the EB-66. In October 1966, the Marine Corps acquired the EA-6A and it first saw combat in Vietnam in 1967. The EA-6A performed admirably in combat, so well in fact that it severely clouded the issue of whether the Navy needed its proposed version of a tactical EW dedicated aircraft. Navy and Marine Corps leaders eventually teamed up to develop the first fully integrated tactical EW dedicated aircraft: the EA-6B. The EA-6A is the forefather of the EA-6B; the EA-6B is the forefather of the Air Force's tactical EW aircraft, the EF-111A. With a short history of EW provided, we will now focus in on the US's two tactical EW aircraft: the EA-6B and the EF-111A. We will take a look at the history and capabilities of each aircraft. Grumman won the development contract for the EA-6B, commonly referred to as the "Prowler", in the fall of 1966; the EA-6B flew for the first time on 25 May 1968. The Navy accepted the first of twelve production aircraft in January 1971. The last of 164 production aircraft arrived at NAS Whidbey Island in 1991. (6:418-419) The Navy currently maintains fifteen EA-6B squadrons, including two reserve squadrons. The Marine Corps first received the EA-6B in September 1977 and currently maintains four squadrons for a total of twenty-four aircraft. There are a total of 130 EA-6Bs currently in the Navy and Marine Corps. (5) The EA-6B has undergone numerous upgrades and modifications to improve its capabilities. The four upgrades range from the standard version to the current version: the Improved Capabilities 2 (ICAP 2). In January 1975, Grumman won the development contract to convert the F-111A to the EF-111A. The first EF-111A, also called the "Raven", flew its initial flight on 15 December 1975. Full scale conversion of forty-two EF-111As began in January 1983. The Air Force currently maintains two EF-111A squadrons. The 390th Electronic Combat Squadron became operational with the EF-111A in December 1983. The first EF-111A assigned to the 42nd Electronic Combat Squadron arrived in February 1984. (7:419) Currently the USAF maintains forty EF-111As. The EF-111A has undergone four upgrades to improve its capabilities. CAPABILITIES The EA-6B Prowler carries a crew of four: one pilot and three Electronic Countermeasures Officers (ECMO). The EA-6B's maximum speed is 530 knots and has an endurance of almost three hours in a combat configuration. The EA-6B uses the AN/ALQ-99 Tactical Jamming System (TJS). This system is the most sophisticated airborne TJS in the world today. (6:418-419) The AN/ALQ-99 TJS is capable of conducting both ECM and ESM missions. A digital tape recording system enables the ECMO to record all electronic emission data during a flight, enabling the construction and analysis of the EOB by intelligence personnel. Analysis of the electronic data, on the digital tapes, by the Tactical Electronic Reconnaissance Processing and Evaluating System (TERPES) is a unique capability that, at present, only the Marine Corps possesses. TERPES is tied into the global intelligence network and provides the warfighter with a near real time intelligence capability. For computerized mission planning, both the Navy and the Marine Corps use the Tactical EA-6B Mission Planning System (TEAMS). The mission planning data is downloaded, from TEAMS, to a digital tape and then uploaded into the EA-6B in minutes. This same digital tape records the electronic data for post flight mission analysis. The Prowler is capable of carrying five external jamming pods with two transmitters each for a total of ten jammers. The EA-6B can also launch the High Speed Anti-Radiation Missile (HARM) and routinely deploys aboard aircraft carriers. The EF-111A carries a crew of two: a pilot and an Electronic Warfare Officer (EWO). The Raven's maximum speed is 1,196 knots and has an endurance in excess of four hours. The Raven uses the AN/ALQ-99E TJS, a modified version of the Prowler's TJS to perform its ECM and ESM missions. (7:419) The AN/ALQ-99E possesses critical deficiencies when compared to the Prowler's AN/ALQ-99 system but due to the unclassified nature of this paper, these differences cannot be delineated. The EF-111A currently possesses no capability for computerized mission planning nor can electronic data be recorded for post flight mission analysis. The Raven carries a maximum of ten jammer transmitters. The EF-111A is not carrier capable. PERFFORMANCE DURING THE GULF WAR The Gulf War provided the US military an opportunity to battle test many weapon systems, to include the EA-6B and the EF-111A. Although EN effectiveness is sometimes difficult to assess, the Raven and the Prowler proved themselves worthy of great respect. Numerous post war debriefs stated that the EA-6B and the EF-111A performed superbly and that we needed more of them. The EA-6B proved so essential that the EA-6B became a go/no-go criterion for many strikes. (2) Coalition air forces consistently asked for the EA-6B by name. Twelve Marine Corps Prowlers from Marine Tactical Electronic Warfare Squadron Two (VMAQ-2) deployed to Southwest Asia (SWA). A Prowler from VMAQ-2 remained on station twenty-four hours a day during Operation Desert Storm. VMAQ-2 flew a total of 516 sorties, flying 1,622 hours. The Marines from VMAQ-2 fired twelve HARMs. No combat air losses, from radar guided SAMs, occurred when supported by EA-6Bs. (2) Navy EA-6Bs experienced similar success as the Marine Prowlers. Twenty-seven Navy EA-6Bs, embarked on six aircraft carriers, flew 1,107 sorties for a total of 2,978 hours during the Gulf War. The Navy used the HARM capabilities of the EA-6B to a greater extent than the Marine Corps. Navy EA-6Bs performed Suppression of Enemy Air Defense (SEAD) missions, both jamming and shooting HARM at Iraqi radars. Navy Prowlers shot 138 HARMs, mostly during the early days of the war. No EA-6Bs were lost during Operation Desert Storm. (4:687) A total of twenty-four EF-111As conducted combat operations out of two bases in SWA. (4:106,108) According to Air Force Component, Central Command, the EF-111A flew 917 sorties accumulating 4,564 flight hours during the Gulf War. EF-111As enjoyed much the same success as did the EA-6Bs except for their inability to shoot HARM. The Air Force lost one EF-111A during Desert Storm, but it is unclear as to whether this loss was due to enemy action. The combination of ECM, HARM, and bombing strikes had a dramatic affect on Iraqi air defenses. The Iraqi early warning, SAM, and AAA radars activity dropped 88% in the first three days of the war and stayed there the rest of the war. (4:150) Radars stayed on only short periods of time and immediately went down as soon as ECM aircraft started jamming. Most radar guided missiles were either launched without guidance or with insufficient tracking time to effect a kill on coalition aircraft. The successful use of EW greatly contributed to the low loss of aircraft and airmen. We must not learn the wrong lessons from the Gulf War when it comes to EW. The Iraqis did not employ the full range of threat systems available to third world countries, and they did not employ those that they had effectively. We can expect to encounter a more sophisticated and effectively used air defense system in future conflicts. With Russia hard pressed economically, more of its advanced technology weapons will be sold to obtain hard currency. Therefore, we must continue to develop systems that will counter these threats. THE PROBLEM For a number of reasons, two different types of tactical EW aircraft continue to evolve creating a problem that needs to be addressed and solved by military leaders before it is addressed by others, who may not understand the problem as clearly. The Air Force continues to develop the EF-111A while the Navy/Marine Corps continues to develop the EA-6B. The US military should eliminate the EF-111A and replace it with the EA-6B. Examples of the problem will enable the reader to better understand why a solution is needed. The duplication of assets performing the same mission presents many problems. First, the duplication increases overall costs. Procuring two types of aircraft raises the unit cost per aircraft. The ALQ-99 TJS is common to both aircraft. However, the significant differences in airframes require a separate program development and management system. The duplication causes a second problem: the logistic support system required to maintain two different aircraft is significantly greater than that of maintaining one system. Both aircraft are derivatives of other aircraft: the EA-6B, a derivative of the A-6, and the EF-111, a derivative of the F-111A. While there is some commonality of parts among the derivatives, a number of components are EA-6B and EF-111A-specific. Included in the costs to support the two aircraft are increased maintenance-worker training and increased publication production costs. These two costs alone require a significant increase in the logistic support system. Finally, unity of effort is impaired due to separate research and follow-on development programs required to upgrade and improve capabilities. The difference in airframes and user requirements requires two separate acquisition and research fund pipelines, which in turn increase costs. These two pipelines inevitably led to and will continue to lead to disparities in capabilities between the two aircraft. THE SOLUTION The solution to this problem is simple: eliminate the EF-111A and replace it with the EA-6B. This would solve many problems. First, this would cut aircraft procurement costs. The EF-111A Systems Improvement Program (SIP) will upgrade the Raven at a cost of approximately 431 million dollars. The scheduled conversion of 102 of the 130 EA-6Bs to EA-6B ADVCAPs will cost approximately 750 million dollars. The conversion of an additional twenty-eight EA-6Bs to EA-6B ADVCAPs, along with the purchase of an additional twelve production EA-6B ADVCAPs would significantly lower the EA-6B's unit cost per aircraft for both the conversion and production aircraft while meeting both the Navy/Marine Corps and the Air Force EW requirements. The oldest EA-6B airframe is not scheduled for retirement until 2015. (5) The EA-6B program is a long term plan, over twenty years, that would allow for the phasing in of follow on aircraft in a timely manner. Second, the elimination of the EF-111A would allow for the streamlining of two logistic support systems into one system. This would reduce the amount of personnel, publication, and maintenance-worker training required. Reduced support costs, with only one logistic system, are also realized. Intermediate Maintenance Level repair facilities are available to support Air Force needs due to the reduction in aircraft carriers and Navy EA-6B squadrons. Finally, reducing two separate research and acquisition fund pipelines not only allows for a reduction in costs, but it also enables our scientific community to focus on one product for both military services. The net result is reduced military costs and state of the art capabilities for the US military. Using the EA-6B as the tactical EW aircraft for the US military enhances the US's warfighting capabilities. The EA-6B is a much more capable aircraft. With the EA-6B ADVCAP coming on line, in 1996, the gap in capabilities between the EA-6B and the EF-111A will widen appreciably. The EA-6B ADVCAP program is a three phase program currently under full scale development. The first phase, the Receiver Processor Group (RPG), is complete. This phase saw a complete upgrade to the AN/ALQ-99 TJS. The new system will enable the Prowler to detect and jam emitters in bands one through ten. The AN/ALQ-149 will allow the Prowler to jam radio communications. The jammer subsystem will use the digitized Universal Exciter Upgrade (UEU). The UEU will be compatible with both the communication and radar jammers, covering the extended bandwidth brought by the AN/ALQ-149. (1:49-50) The second phase, the Vehicle Enhancement Program, will upgrade the airframe itself. Included in this is a digital flight control system, maneuvering flaps and slats, and new engines to increase performance, safety, and flight handling characteristics. The addition of two external store stations will enable the Prowler to carry an additional two jamming pods or two HARMs. This phase is currently undergoing flight testing. The third phase, the Avionics Improvement Program, will provide the aircrew with modern digital flight instrumentation and cockpit layout improvements. This phase is scheduled to begin flight testing in June 1993. Full scale production is scheduled to begin with initial delivery slated for 1996. (5) The EA-6B ADVCAP will continue to require four aircrew positions, vice two for the EF-111A, enabling the EA-6B to handle a larger and more complex number of missions simultaneously. This is a comprehensive package that will dramatically improve the EW and safety characteristics of the EA-6B while economically using existing airframes. The EA-6B ADVCAP program will meet the EW challenges of the early twenty-first century. The EF-111A is currently undergoing the SIP upgrade. One aircraft is under full scale development. This upgrade will provide improvements to the AN/ALQ-99E system but will fall far short of the capabilities of the EA-6B ADVCAP program. There will still be no communication jamming capability and the radar jamming capability will fall well short of the Prowler's UEU jammer subsystem. A tape recording and computerized mission planning interface capability is planned. The SIP program should meet the Air Force's EW needs through the nineties. (1:50) The EA-6B ADVCAP is clearly the best tactical EW aircraft ever developed. The superior EW, HARM, and carrier capabilities sets the EA-6B well above the EF-111A. The Raven's SIP program will bring its EW capabilities almost up to the current EA-6B ICAP-2. (15) Continued development of the EF-111A will leave the US Air Force with a twentieth century technology aircraft in the twenty-first century. In this day of drastic military cuts further development of the EF-111A puts the EA-6B ADVCAP program at greater risk and underscores the crux of the problem: there are too many different types of tactical EW aircraft in the US military. The US military operates and will continue to operate in a joint environment. Interoperability will be a critical issue. The EA-6B ADVCAP will enhance interoperability in a number of ways. First, all military forces will be familiar with the EA-6B ADVCAP. Second, planning and executing missions will be easier because everyone will understand the EA-6B ADVCAP's capabilities and how to employ it. Finally, the biggest benefit is that combat aircrew will be supported by the best tactical EW platform in the world. 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