In the first half of the twentieth century, guns were the primary weapons used against aircraft. The small arms weapons typically fire ball ammunition, or armor-piercing projectiles, known as AP rounds, or AP projectiles with incendiaries, known as API rounds. The AAA weapons and the larger-caliber aircraft guns usually fire ballistic projectiles with a high-explosive (HE) core and a surrounding metal case. These are referred to as HE warheads or HEI warheads when incendiaries are included. After World War II, guided missiles, both surface-based and airborne, were developed to kill aircraft. These anti-air weapons typically carry contact- or proximity-fuzed HE warheads designed to kill aircraft with fragments and blasts.
Current aircraft have become vulnerable to sophisticated networked surface-to-air missile batteries produced by Russia and China, which could destroy early warning aircraft, tactical fighters, and even stealth bombers. The proliferation of surface-to-air missiles and long-range tactical missiles reduces the area where U.S. forces can operate. China reportedly has received its second set of S-400 surface-to-air missile systems from Russia, marking a potentially major improvement of the country’s air-defenses.
“A new missile with a longer range specifically developed for Russia’s S-400 air defense system will push the range at which the system can engage targets to its limit,” according to Russian military industry source. Each S-400 battalion has eight launchers, a control centre, radar and 16 missiles available as reloads. It has the capability to hit missiles and aircraft of all types, including stealthy ones 400 km away at a blistering speed of 17,000 km an hour. It can engage up to 36 targets at once, firing 72 missiles toward them.
“It has many features specifically designed to overcome countermeasures and stealth, such as larger, more powerful radar that is more resistant to jamming. It also actually has a set of three missiles of varying range that provide overlapping layers of defense,” Ivan Oelrich, an independent defence analyst told The Diplomat.
Guns and guided missiles are still the primary threat faced by aircraft today. However, several new threats to aircraft are in development. Directed energy weapons, in the form of low-to-medium power lasers and high-power microwaves, have the potential to damage or destroy sensors on the aircraft and the weapons they are carrying; and high-power lasers can damage major aircraft structure.
Chemical and biological weapons pose a threat to aircraft, particularly on the surface, and nuclear weapons are a threat to aircraft on the surface and in the air, says Committee on Weapons Effects on Airborne Systems, Air Force Studies Board, Commission on Engineering and Technical Systems, National Research Council.
With the increasing proliferation of shoulder-launched IR missiles and other effective, but low cost threats, most helicopters, fixed-wing aircraft, and unmanned aerial vehicles (UAVs) are highly vulnerable to attack in combat and other hostile environments. That is why improvements and upgrades to aircraft survivability equipment and related threat management solutions are consistently in high demand worldwide, especially for military and head-of-state platforms.
Aircraft Survivability
Survivability is defined as the capability of a system, including its crew, to avoid or withstand a hostile environment without suffering an abortive impairment of its ability to accomplish its designated mission. With the development of precision-guided weapons, particularly radar-guided missiles and infrared-guided missiles, aircraft combat survivability is becoming increasingly important. Eastern Ukraine incident in 2014 demonstrated the vulnerability of aircrafts where a passenger jet was downed by a surface-to-air missile, killing all 298 people aboard, and fired from territory held by pro-Moscow separatists.
With rising threats new technologies are being devised to enhance the survivability of aircrafts from Advanced Threat Detection/Avoidance Components and Techniques, laser directed energy weapons, Electronic Warfare Countermeasure Systems and Techniques to cyber warfare are being developed. Aircraft survivability relies on a hierarchy of stages to return the aircraft to service. If an aircraft cannot avoid detection, it should try to avoid engagement. If the aircraft is engaged, it should then try to avoid or absorb damage, and if all else fails at least attempt to avoid destruction.
Usually survivability can be subdivided into susceptibility and vulnerability, referring to the inability of an aircraft to avoid and withstand the man-made hostile environment, respectively. Aircraft combat survivability can be also defined as the probabilistic values that the aircraft would survive in man-made hostile environment, with the antithesis killability. The more susceptible and vulnerable the aircraft in the hostile environment, the more killable and lower survivable the aircraft.
The factors affecting susceptibility include radar signal character, infrared signal character, visual signal character, maneuverability character, and ECM (electronic countermeasure) character. Radar is one of the most lethal threats for aircraft. For example, early warning radars can provide airborne target information out of hundreds of miles, while ground control interceptor can even provide an accurate target location. Most consider aircraft survivability only about reduction of aircraft radar signature, or radar cross section (RCS), through shaping and materials. Lowered RCS reduces the range at which a threat radar can detect, locate and identify a target— a significant military advantage.
Infrared signal is another important signal character of the aircraft. With the development of stealth and antistealth techniques, the aircraft’s RCS has decreased significantly. However, compared with the environment, infrared signal is still significant even for the stealth aircraft. In the war area for 20 years, about 90% of airplanes were damaged by the infrared-guided missile. Nowadays, IRST (infrared search and track) system, FLIR (forward looking infrared) system, and infrared-guided missiles have been significant threats by accurately locating aircraft. Visual signal is another important factor in determining overall aircraft detectability.
Maneuverability is an effective means of defense for the aircraft against detection and attack. Supersonic maneuver is now the standard of new generation aircraft. Supersonic maneuver gives an aircraft a lower susceptibility and a higher survivability. Electronic countermeasure plays an important role in modern military affairs, including active and passive jamming, which is an effective mean to decrease aircraft susceptibility and enhance aircraft survivability. Electronic countermeasure equipment contains omnidirectional radar warning equipment, radar chaff dispensing device, infrared jammer, and infrared-guided missiles.
The other half of survivability — vulnerability — is the ability to withstand damage to the aircraft or preclude injury to the occupants from threats; natural (e.g. trees), man-made (e.g. rocket-propelled grenades), and from ground impact — termed crashworthiness. Aircraft vulnerability refers to the inability of an aircraft to withstand the man-made hostile environment, which lies on ratio of fatal components, redundant ratio of fatal components, shelter ratio of fatal components, average killing probability, and average safety factor.
Vulnerability is far more significant for vertical flight aircraft, operating in close proximity to complex and dynamic terrain, based at austere and unprepared sites, and close to ground threats.
An even more important factor for victory is the availability of the force. having sufficient capability or the most equipment available to continue to operate in the entire campaign, to be the victor on the last day of the war. Of course, surviving is a key factor in remaining available, the availability, sustainment, and maintainability are equally important. Technology to advance availability can enhance our capability to be victorious and free up downstream funds for more investments.
Aircraft Survivability Equipment (ASE) requirements
The role of Aircraft Survivability Equipment (ASE) is to reduce the vulnerability of aircraft, thus allowing aircrews to accomplish their immediate mission and to survive. Historically, survivability in the presence of a threat has been characterized as a hierarchy of stages. The first stage is to avoid detection by the threat. If the aircraft cannot be detected by the threat, survivability is ensured.
Stealth technology has proven to be one of the effective approaches to enhance the survivability of Aircrafts. Aircraft/helicopter designers are making them stealthier by reducing their signatures; viz. visual, aural, infrared (IR), and RADAR cross section. Advancements in stealth technologies, as demonstrated by the very low RCS of stealth aircraft such as F-117, B-2 and F-22, make such targets extremely difficult to detect.
However, if it is impossible to avoid detection, the next stage is to avoid engagement. If the aircraft can be detected by the threat but cannot be engaged, survivability is again ensured. When it is impossible to avoid engagement, the next stage is to avoid or absorb damage to the aircraft. Finally, when it is impossible to avoid damage, the last stage is to avoid destruction of the aircraft. A variety of different survivability systems and technologies are responsible for addressing each stage of this hierarchy.
Brig. Gen. Robert Collins, Program Executive Officer — Intelligence, Electronic Warfare & Sensors, emphasized the need for ASE solutions to fit within the open architecture framework. “An open systems architecture allows us to keep pace of the threat. It affords us the ability to perform agile technology evolutions while driving SWaP (Size, Weight and Power) and cost down,” said Collins. “As part of this endeavor it will allow industry to have increased opportunity for competition.”
At the Project Manager level, there is a significant focus on increasing capability, reducing the SWaP burden on the aircraft and decreasing downtime. “In order to get on our aircraft you need to have these considerations in mind: weight is always a concern and the more multi-spectral a system can be the better off it is,” said Col. Kevin Chaney, Project Manager Aircraft Survivability Equipment.
With SWaP a major concern, PM ASE is looking at opportunities to consolidate the number of processors needed to operate ASE systems, so that each individual ASE system doesn’t require its own processor, rather it can reside on the Aviation Mission Common Server. Additionally, they are looking into the ability to have just one A kit (mountings, cables, etc.) that would also drive down the weight burden on an aircraft.
From a downtime perspective, Chaney shared a look at a new modification initiative where 11 separate modifications are being made to Blackhawk aircraft at the same time. By performing a consolidated modification PM ASE along with partners from PEO Aviation are planning to reduce a previously combined 3000 hours for modifications to at least less than half that time.
The need for ASE solutions to be developed quickly and be easily adaptable said Maj. Gen. David Francis, Commanding General U.S. Army Aviation Center of Excellence. “We have an opportunity to modernize before we get to a point where it is catastrophic,” said Francis. “We absolutely have to re-think how we address survivability problems in Army Aviation — in the past as we encountered a threat we would study that threat, we would develop countermeasures, but it was years in the making. We don’t have that luxury anymore, we have to absolutely be able to advance from a threat agnostic point of view to be able to rapidly integrate ASE solutions into our systems.”
Missile Warning Receiver
The Radar Warning Receiver (RWR) detects, categorizes, and prioritizes Radio Frequency (RF) emitters and provides a visual / aural alert to aircrew members warning them of targeting by RF-guided weapons. The Electronic Countermeasures (ECM) jamming capability then allows jamming of the target.
Long-wave infrared (LWIR) Light Detection and Ranging (LIDAR) system
Army under SBIR Program has called for Development and demonstration of a long-wave infrared (LWIR) Light Detection and Ranging (LIDAR) system for Army aircraft optimized for aircraft survivability. A LIDAR operating in the LWIR would provide new capability in terms of ranging and tracking next generation surface to air missiles at enhanced ranges, as well as capability in degraded visual environments
LWIR LIDAR technology offers a promising supplement to the modern Aircraft Survivability Equipment (ASE) suite. Threat warning systems are designed to detect incoming threats and provide a cue to countermeasure systems. The long-wave LIDAR system shall assess objects of interest at ranges up to 6km, and shall have a resolution of at least 50 microradians with a frame rate capable of 60Hz to determine trajectory information. All this information would then be provided to the onboard ASE suite.
Future objectives include integration of the LWIR LIDAR system with existing countermeasure systems and development of detection and false-alarm reduction algorithms. This operational capability will support increased aircraft survivability in a wide range of environments. Follow-on science and technology efforts will mature the LWIR LIDAR technology and support integration with the aircraft survivability suite and technology developed in the Multi-Spectral Threat Warning S&T Effort.
In military applications, the capability is expected to support the ongoing development of a holistic suite of integrated aircraft survivability equipment. The LWIR LIDAR would provide information on objects of interest to the cognitive integration algorithms in conjunction with other on-board aircraft survivability equipment. The inclusion of the LWIR LIDAR as an additional data source will improve the effectiveness of the overall suite of equipment. In addition, potential commercials applications include LWIR imaging systems for surveillance, automotive systems, and thermography.
Although radar is used in many of these threats to detect and track the aircraft, an increasing number of systems use electro-optical sensing for this purpose. These mostly passive systems, however, are much harder to detect and identify than the radar equivalents (for which warning and positioning capabilities are already well established). New threat detection systems are therefore required to detect the next-generation of antiaircraft missiles
Common Missile Warning System (CMWS)
The US Army operational requirements concept for Aviation Infrared (IR) countermeasure systems is known as the Suite of Integrated Infrared Countermeasures (SIIRCM). SIIRCM is an integrated warning and countermeasure system to enhance aircraft survivability against IR-guided threat missile systems. The Common MissileWarning System (CMWS) is a core element of the SIIRCM concept. CMWS is an integrated ultraviolet (UV) missile warning system, with an Improved Countermeasure Dispenser (ICMD) serving as a subsystem to a host aircraft
Army moves ahead with laser-based Common Infrared Countermeasure (CIRCM)
The Common Infrared Countermeasure, or CIRCM, under development now by both BAE and Northrup Grumman, is being designed to provide automated countermeasures primarily against man-portable air defense systems, which fire missiles from the ground and use infrared capability to guide those missiles, according to an Army release. CIRCM works in combination with the missile warning system to detect and defeat MANPADS. CIRCM system primarily includes three components: a pointer/tracker unit, laser, and system processor unit.
CIRCM will push warnings on potential infrared threats on the Common Missile Warning System (CMWS), an existing early warning system with the role of detecting and alerting pilots to a possible weapon lock. Once this determination has been made and translated, CIRCM will proceed to deploy either advanced laser technology to jam the missile’s guidance system, or flares to neutralize the threat without the need for human intervention.
Leonardo to co-develop British RAF’S expendable active decoys
Leonardo is to partner with the British Royal Air Force’s (RAF) Rapid Capability Office (RCO) to develop third-generation missile-jamming decoys for use on the RAF fighter aircraft. The incoming missile is drawn to the BriteCloud and misses the aircraft by a large margin, according to the statement.
The RAF has already procured BriteCloud decoys and successfully conducted launch tests from Tornado GR4 aircraft against a range of simulated threats featuring real radar systems in March last year. During the trials, the decoys automatically detected threat radars and jammed them with the decoy’s embedded digital radio frequency memory jammer. The tests demonstrated BriteCloud’s effectiveness against modern threats that could be encountered by pilots.
Infrared Countermeasures (IRCM)
Infrared guidance systems in heat-seeking missiles are designed to track strong sources of infrared radiation – heat – such as aircraft engines, helping missiles to home in on their targets. IRCM systems are based on a modulated source of infrared radiation with a higher intensity than the target itself. When a missile seeker observes this modulated radiation, it interferes with or obscures the modulated signal from the aircraft and renders the missile incapable of maintaining a lock on the target.
Directional Infrared Counter Measures (DIRCM)
Directional IRCM, or DIRCM, allows for a countermeasures laser to be targeted directly at an incoming IR threat. This makes possible a more powerful and effective defense than previous, non-directional infrared countermeasures, as the threat is directly addressed rather than the system essentially painting an area with IR disruption, which results in a weaker signal in any given direction.
As IR seeking technology has improved and diversified, standard IRCM systems have become less effective at defeating heat-seeking missiles. Measures such as flares have begun to give way to lasers, which, when fitted on a directional pivoting mount, allow for more effective, concentrated and energy-efficient directional targeting of IR radiation at incoming missile seekers.
Directional IR countermeasures (DIRCM) systems on aircraft are designed to track, and direct energy toward, a threat. In particular, preemptive DIRCM systems should be able to detect, identify, and counter a threat before any missile (or other weapon) has even been fired. In the past, preemptive DIRCM system technologies have been studied as part of the Defense Advanced Research Projects Agency’s (DARPA’s) Multifunctional Electro-Optics for Defense of US Aircraft (MEDUSA) program. In preemptive DIRCM systems, it is important to detect and analyze several different signatures, including ones that are not treated in conventional DIRCM systems.
Such signals may include laser emission from the target, retro-reflections from optical sights and seekers, or the optical signatures of the weapon and operator (including the aiming and tracking activity).
Electronic Warfare and electronic attack
Saab has unveiled details of a future fast jet airborne electronic attack (AEA) capability concept combining a high-power escort jamming pod, long-range air-launched decoys, and advanced electronic warfare (EW) operator control and fusion techniques. Outlining an increasingly complex and challenging anti-access/area denial (A2/AD) environment, Jonas Grönberg, the company’s Head of Product Management for Fighter EW, argued that the emergence of new low-band early warning radars means “low observability is no longer a substantial defence for strike aircraft”, advocating instead “high-powered electronic attack to deny shared situational awareness and targeting data, and to negate data networks”.
Saab in 2013 began its in-house study to characterise the future air operating environment so as to inform key requirements and technologies for combat aircraft in the 2035–40 period. One key conclusion to emerge from this work was the requirement for a credible AEA capability, supporting suppression of enemy air defences/destruction of enemy air defences, to improve aircraft survivability, and enable penetration of the A2/AD screen. “It turned out that EW came out as a common enabler,” Grönberg told Jane’s in a subsequent interview. “The survivability of any platform will require much enhanced EW capabilities. Even the latest low observable technology will not render an aircraft invisible.”
Central to Saab’s thinking is the development of a self-contained (in cooling and power) electronic attack (EA) pod suitable for two-seat variants of the JAS 39 Gripen or other twin-crew fighter aircraft. EA pod concept studies and design, including the build of engineering mock-ups, have been founded on the reuse of technology building blocks previously developed for the Gripen E’s internal self-protection EW suite. The pod design developed by Saab incorporates VHF and UHF antennas in fin surfaces, with L-band and S-band active electronically scanned array antennas, based on gallium nitride technology, fitted front and rear.
The second element of the triad is a miniature air-launched decoy to perform both distraction and stand-in jamming. Saab has conceptualised a small, long-range, long-endurance decoy vehicle with an EW payload that can locate and identify threats and targets, and distract enemy air defence resources. The decoy will support an attack on a target defended by surface-to- air missile systems by acting as a stand-in jammer.
The third piece of the new concept is the development of a back-seat electronic warfare officer (EWO) station embodying advanced sensor data fusion and decision support techniques. Saab has already prototyped the EWO human machine interface in the simulator, and has shown it to the Swedish Air Force
Cyber Warfare to counter or spoof enemy missiles
Pentagon believes it has a potent new weapon against networked surface-to-air missile systems: cyber weapons to counter or spoof them. “How do we provide blunt force trauma from an air component perspective in the cyber domain?” Gen. Mark Welsh, the U.S. Air Force chief of staff, said at a Defense Writers Group. “What does that mean?
Welsh provided some possibilities: It could mean making the enemy’s air defense system go completely blank on the first minute of the conflict. Or making surface-to-air missile radar see a thousand false targets while an aircraft sneaks through in plain sight. Or preventing a missile from launching. Or directing it to turn around and strike its own launch site
Laser Directed Energy Weapons for Aircraft Survivability
Mica Endsley, a chief scientist with Air force said, “We will be transitioning into airborne platforms to get them ready to go into program of record by 2023”. Endsley added that the Airforce plans to start using the technology with large transport planes until miniaturization efforts allow the weapon to fire from fighter jets. The Air Force scientist said the laser system could be used for air-to-air combat, counter drone, counter-boat, ground attack, and missile defense. She added that the energy to fire an aircraft laser cannon would come from on-board jet fuel, allowing for thousands of shots.
“The real advantage is it would have a much more extended magazine. Instead of having five, six, seven missiles today, with a directed energy weapon, you could have thousands of shots with a gallon of gasoline – a gallon of jet fuel,” Endsley said. Air Force Research Laboratory released a request for information (RFI) for a laser weapon that could be mounted on next-generation air dominance fighters by the 2030s. The Air Force is interested in three categories of lasers: low-power for illuminating, tracking, targeting, and defeating enemy sensors; moderate-power for protection to destroy incoming missiles; and high-power to offensively engage enemy aircraft and ground targets. The Air Force plans to scale-up laser weapon to 150 kW and then 200 kW. A 200 kW laser cannon will be able to destroy surface-to-air and air-to-air missiles apart from armored vehicles on the ground.
US Army’s requirement on Future Aircraft Survivability
The US Army’s Communications-Electronics Research, Development and Engineering Center (CERDEC) Intelligence and Information Warfare Directorate (I2WD) has called for RFI to identify technology options and innovative approaches supporting aircraft survivability suite of 2025 and beyond.
The options and approaches provided will consist of both threat warning systems and countermeasure systems addressing following topics:
• Aircraft Survivability Equipment (across RF/UV/EO/IR spectrums)
• Integrated Aircraft Survivability Solutions
• Electronic Warfare Countermeasure Systems and Techniques
• Advanced Threat Detection/Avoidance Components and Techniques
• Degraded Visual Environment
Contemporarily the Aircraft survivability is provided by collection of individual technologies, each designed to be independently effective at detecting or defeating a specific class of weapon systems, such as electro-optic and radio-frequency guided missiles or ballistic munitions.
According to CERDEC this presents several disadvantages, independent design and development of the systems results in duplication of components, such as processors or displays that would be unnecessary if the systems were integrated. The lack of integration also prevents onboard systems from communicating with one another and operating cooperatively, which limits reliability and adaptability. For example, if a single protection system fails or is destroyed, the other onboard systems cannot intelligently compensate for that loss
Integrated Air and Ground Survivability
The US Army’s Communications-Electronics Research, Development and Engineering Center (CERDEC) Intelligence and Information Warfare Directorate (I2WD)’s Integrated Air and Ground Survivability strategic focus views survivability from a holistic perspective rather than seeing survivability systems as independent entities. Rather than seeing survivability systems as independent entities, battlefield survivability systems are viewed as a distributed, coordinated network of capabilities.
When Army Aviation encounters threats, the systems on the network autonomously collaborate with one another to avoid detection, avoid engagement and subsequently avoid damage and destruction. At each stage, the network accesses information from all survivability systems on the battlefield as well as from the intelligence enterprise. If detection cannot be avoided, the network uses available information to locate and identify the threats. The network then prioritizes the threats, considers available resources and implements optimal countermeasures for each threat. This effort’s long-term vision establishes a cognitive survivability suite, capable of coordinating all survivability systems’ activities on the battlefield.
Under the Integrated Air and Ground Survivability Concept, the future survivability suite is composed of a distributed network of aircraft survivability equipment and electronic warfare systems across individual air and ground platforms. These systems communicate autonomously with other onboard systems as well as with systems on other platforms. The data sharing improves the individual systems’ performance and group of systems’ performance through automatic prioritization and response coordination.
At the platform level, the future integrated air suite is coordinated through a cognitive integration framework and a realtime engagement controller. The cognitive integration framework provides the physical connections between onboard systems and the central processing capability to correlate and analyze data. The realtime engagement controller is a software application that operates on top of the cognitive integration framework. The application has access to data from all onboard survivability systems, including missile warning systems, hostile fire detection systems, laser warning receivers, radar warning receivers, and electrooptic and radiofrequency countermeasure systems. This application continuously assesses data from the onboard survivability systems to detect potential threats.
As the platform encounters threats, the engagement controller utilizes advanced cognitive algorithms to locate and identify threats and then designs optimal countermeasures. The engagement controller is implemented with an opensoftware architecture that enables new data sources to be easily incorporated into the existing framework. At the between platform level, individual platform integrated air suites are integrated into a network that continuously shares information and access to resources . The engagement controller on each platform
will incorporate information from other platforms when assessing and locating potential threats. Following the identification of threats, the integrated suites collaborate to implement a coordinated countermeasure response, leveraging assets from all available platforms. In the longterm, the network of integrated air systems is also integrated with a corresponding network of integrated ground survivability systems.
Aircraft Survivability Equipment market
Aircraft Survivability Equipment market worldwide is projected to grow by US$1. 7 Billion by the year 2025, driven by a compounded growth of 5. 6%. Representing the developed world, the United States will maintain a 6.6% growth momentum. Within Europe, which continues to remain an important element in the world economy, Germany will add over US$83.9 Million to the region’s size and clout in the next 5 to 6 years. Over US$76.3 Million worth of projected demand in the region will come from Rest of Europe markets. In Japan, Combat Aircraft will reach a market size of US$146.6 Million by the close of the analysis period. As the world’s second largest economy and the new game changer in global markets, China exhibits the potential to grow at 5.2% over the next couple of years and add approximately US$280.3 Million in terms of addressable opportunity for the picking by aspiring businesses and their astute leaders.
The key players in this market include, among others, Aselsan A.S., BAE Systems PLC, Chemring Group PLC, Elbit Systems Ltd., Israel Aerospace Industries (IAI), Northrop Grumman Corporation, Raytheon Company, RUAG Holding AG, SAAB AB, Terma A/S and Thales Group
Reference and Resources also include:
https://www.nap.edu/read/12470/chapter/3
http://www.globalsecurity.org/military/library/budget/fy2016/army-peds/0605051a_5_pb_2016.pdf
http://www.janes.com/article/74074/arexis-airborne-attack-dsei17d4
https://www.army.mil/article/230819/army_aviation_community_focuses_on_aircraft_survivability