Category Archives: Agusta Westland

Intellegent Warfare: Electronic Support Measures and Application of HARM Missile

USS KITTY HAWK (CV 63), At Sea (November 9, 2005) – Aviation Ordnanceman prepare to load a CATM-88 Harm missile onboard the USS Kitty Hawk (CV-63). While at sea, Kitty Hawk and Carrier Strike Group 5 will be participating in an annual exercise with the Japanese Maritime Self Defense Force. Currently underway in the western Pacific Ocean, Kitty Hawk Carrier Strike Group demonstrates power projection and sea control as the Navy's only permanently forward-deployed aircraft carrier strike group, operating from Yokosuka, Japan. U.S. Navy photo by Photographer’s Mate 3rd Class (AW) Jonathan Chandler.

After writing few posts discussing the technological influence on defence stratagies of different nation, this time I thought to go slightly technical. A reader may use this information as an extension of my discussion on Electronic Warfare – Electronic Warfare Operations Warfare has always been conducted by adversaries who have been at great pains to understand their enemy’s strengths and weaknesses in order to minimise the risk to their own forces and territory. The detection and interception of messages and the efforts to deceive the enemy have long been the task of the ‘secret service. As methods of communication developed, so too did methods of interception become more effective. Radar has developed from a mere detection mechanism to a means of surveillance and guidance. This post is focuses on gathering information on immediate threats which is performed by Electronic Support Measures (ECM)

MH-53 Pave Low helicopters prepare to take off for their final combat mission on Sept. 27, 2008, in Iraq. The MH-53, the largest and most technologically advanced helicopter in the Air Force with a record dating back to the Vietnam War, was retired from the Air Force inventory on Sept. 30, 2008

Electronic Warfare (EW) planning requires a broad understanding of enemy and friendly capabilities, tactics, and objectives. Employment of EW assets must be closely integrated into, and supportive of, the commander’s overall planning effort. This planning requires a multidisciplined approach with expertise from operations (ground, airborne, space), intelligence, logistics, weather, and information. Application of this sort of EW planning and employment was seen in Operation Desert Storm in 1991. three US Air Force MH-53J PAVE LOW helicopters (shown above) led nine US Army AH-64 Apache helicopters across the Saudi Arabia-Iraq border to attack two Iraqi early warning radar sites. Taking down these two sites opened the door for attacks across Iraq by F-117s, other coalition aircraft and Tomahawk missiles (shown below).

Block IV Cutaway - Raytheon

After the F-117s and cruise missiles came conventional aircraft. From 0355L to 0420L (H+55 to H+1:20) large numbers of USAF, USN, USMC, RSAF, and RAF aircraft smashed Iraqi air defenses and fields from H-3, an airfield located in western Iraq, to Ahmed Al Jaber, an airfield in occupied Kuwait. Two packages of aircraft, one a USN package from the Red Sea carriers and the other a USAF package from the south pointed directly at Baghdad. These “gorilla” packages were intended to seem threatening enough to force the Iraqis to hurl their air resources in defense. Air Force ground-launched BQM-34 and Navy tactical air-launched decoys (TALD) mimicked the radar return of conventional aircraft to further arouse Iraqi radar operators, many already confused by the absence of central control from Kari. Finally, radar-jamming aircraft radiated blanketing electronic emissions that drove the Iraqi radar operators to go to full power in an attempt to break through the interference. Then, the two incoming coalition flights revealed their true nature and pounced in a shrewd and devastating ruse.

The newest upgrade is a joint venture by the Italian Ministry of Defense and the US Department of Defense: the AGM-88E Advanced Anti Radiation Guided Missile (AARGM), produced by Alliant Techsystems.

What was unique here that, instead of bomb-carrying fighter-bombers, they were radar-killing electronic warriors carrying AGM-88 high-speed antiradiation missiles (HARMS) designed to home in on SAM and AAA radar (shown above). The AGM-88 High-speed Anti-Radiation Missile (HARM) is a tactical, air-to-surface missile designed to home in on electronic transmissions coming from surface-to-air radar systems. Originally developed by Texas Instruments (TI) as a replacement for the AGM-45 Shrike and AGM-78 Standard ARM system. Production was later taken over by Raytheon Corporation (RAYCO) when they purchased TI’s defense business. The AGM-88 can detect, attack and destroy a radar antenna or transmitter with minimal aircrew input. The proportional guidance system that homes in on enemy radar emissions has a fixed antenna and seeker head in the missile’s nose. A smokeless, solid-propellant, dual-thrust rocket motor propels the missile at speeds over Mach 2. HARM, a Navy-led program, was initially integrated onto the A-6E, A-7 and F/A-18 and later onto the EA-6B. USAF F-4G Wild Weasels alone expended dozens of HARMS in twenty minutes, while USN/USMC F/A-18s fired one hundred for the night. HARMS filled the air over Baghdad, the site of over one-half of Iraq’s SAM and AAA batteries. Foolishly, the Iraqis did not turn off their radars, even when the HARMS fireballed in their midst; as one USAF flight leader averred, ‘the emitters came on and stayed on for the entire flight of the missiles.’ This deadly surprise not only destroyed many Iraqi radars, it also terrified their operators. For the rest of the war, they showed great reluctance to use radar and often chose to launch their SAMs with optical or even no guidance.

High-speed Anti-Radiation Missile (HARM) – A Little Overview

The initial HARM attack and the F-117 bombings of the Kari system left Iraq’s integrated air defense system shattered, opening up the country so completely that, within days, coalition air-to-air tankers regularly operated in Iraqi airspace. Other non-stealthy aircraft pummeled Iraqi airfields. An anti-radiation missile (ARM) is a missile which is designed to detect and home in on an enemy radio emission source. Typically these are designed for use against an enemy radar, although jammers and even radios used for communication can also be targeted in this manner. This sort of weapons are key to EW inventory. The word “Radiation” here refers to Electromegnetic radiation, not nuclear. The missile is the direct descendant of the Shrike and Standard ARM missiles used in Vietnam. Most ARM designs to date have been intended for use against ground-based radars. Commonly carried by specialist aircraft in the SEAD (Suppression of Enemy Air Defense) role (known to the USAF as “Wild Weasels”), the primary purpose of this type of missile is to degrade enemy air defenses in the first period of a conflict in order to increase the chances of survival for the following waves of strike aircraft. They can also be used to quickly shut down unexpected SAM sites during a raid. Aircraft which fly with strike aircraft to protect them from enemy air defences often also carry cluster bombs and are known as a SEAD escort. The cluster bombs can be used to ensure that after the ARM disables the SAM system’s radar, the command post, missile launchers, and other components or equipment are also destroyed to guarantee the SAM site stays down.

The R-27 is manufactured in infrared-homing (R-27T), semi-active-radar-homing (R-27R), and active-radar-homing (R-27AE) versions, in both Russia and the Ukraine. The R-27 missile is carried by the Mikoyan MiG-29 and Sukhoi Su-27 fighters, and some of the later-model MiG-23MLD fighters have also been adapted to carry it.

The above account of the First Night of Operation Desert Storm was taken from the Decisive Force: Strategic Bombing in the Gulf War by Richard G. Davis. More recently, air-to-air ARM designs have begun to appear, notably the Russian Vympel R-27P. Such missiles have several advantages over other missile guidance techniques; they do not trigger radar warning receivers (conferring a measure of surprise), and they can have a longer range (since battery life of the seeker head is the limiting factor on the range of most active radar homing systems).

Electronic Support Measures

Technically ESM consists of a collection of senstive antennas designed to detect signals in different frequency bands. Often these antennas are grouped at aircraft’s wing tip pod, which allows a wide angle view without causing too much obstruction as well as to enable a fix on the signal source to obtain an accurate Dircection of Arrival (DoA) of the signal. An effective ESM system rapidly identifies the signal band and location, and determines the signal characteristics. A signal analyser then examines the signal characteristics to identify the type of transmitter and the level of threat posed. Even the most cursory of analysis can establish whether the emitter is associated with surveillance, target tracking or target engagement. This analysis can compare the signal with known emitter characteristics obtained from an intelligence database or threat library and known signal types confirmed and new emissions identified and categorised. Every signal identification is logged with date, time and intercept coordinates, along with the known or suspected platform type, and the results are stored.

ESm Pods on Nimrod: As well as providing threat information, ESM is used by maritime and battlefield surveillance aircraft as a passive or listening sensor which adds important information to other sensors. It is especially useful when tracking submarines

Signals received by the electronic support measures system may in some cases be analysed instantaneously to produce an identity for the transmitter of each signal received. Pulse width, Pulse amplitude and carrier frequency are few important parameters. The nature of the pulse shape is used to determine the particular type of transmitter. The scan rate and the pattern of the scan also provide invaluable information about the mode of the transmitter. It is possible to detect the antennas changing from scanning mode to lock-on to tracking and hence determine the threat that the transmitting station poses. As well as providing threat information, ESM is used by maritime and battlefield surveillance aircraft as a passive or listening sensor which adds important information to other sensors.

The salient signal characteristics or discriminators identified during the ESM collection and identification process includes: Signal Frequency (this is to detect the radar type), Blip/Scan ratio (to get the estimate for scan rate, sector scan width and radar bandwidth), Scan Rate, Scan Pattern (Search, track, track-while-scan (TWS) and ground-mapping (GM) modes will exhibit particular characteristics), Signal Modulation (Pulse, pulse compression, pulsed Doppler (PD), a continuous wave (CW) and other more sophisticated forms of modulation are indicative of the emitter mode(s) of operation and likely threat level) and finally Pulse Repetition Frequency (PRF).

Technical details as well as the schemetic of the ESM system can found in any dedicated military systems book, however, those who are Interested to explore more, I will strongly recommend Military Avionics Systems by Ion Mior and Allen Seabridge.

The combination of analysis of all these modes of operation and when they are employed either singly or in combination is vital to establishing the likely capabilities and intentions of a threat platform, especially when used in combination with other intelligence information. Electronic Support Measures may be employed at a strategic intelligence-gathering level using an AWACS (airborne early warning and command system) or MPA aircraft to build the overall intelligence picture and electronic order of battle (EOB). Alternatively, such information may be gathered and utilised at a tactical level using radar warning receivers (RWR), whereby information is gathered and used at the strike platform level to enable strike aircraft to avoid the most heavily defended enemy complexes during the mission.

As I mentioned earlier, this (ESM) is one element of Electronic Warfare. This is because the nature of EW warfare and devices used. The operating frequency ranges for radars are usually very broad, and no single system can cover the whole range for transmission or reception. Hence, most communications and radar systems are designed for use in specific bands. These bands are usually designated by international convention. The main role of electronic warfare is to search these radio-frequency bands in order to gather information that can be used by intelligence analysts or by front-line operators. The information gained may be put to immediate effect to gain a tactical advantage on the battlefield; it may be used to picture the strategic scenario in peace time, in transition to war, or during a conflict. It may also be used to devise countermeasures to avoid a direct threat or to deny communications to an enemy. It must also be observed that such tactics are deployed by all sides in a conflict – in other words, the listeners are themselves being listened to.

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Filed under AAR Corporation, AARGM, Afghanistan, AGm-113 Hellfire, AGM-154 JSOW, Agusta Westland, Air Defence, Anti-Radiation Missiles, ASN Technology, ASN-229A UAV, Asymmetric Weapons, AWACS, Black Hawk, BQm-34, CIA, Cold War, Direct Energy Warfare, Direct Energy Weapons, Electromagnectic Pulses, Electromagnetic Spectrum, F-117, F/A-18, HARM, Lockheed Martin, Lockheed martin F-16, MH-53, MH-53 Pave, NATO, Navy tactical air-launched decoys, Northrop-Grumman, Operation Desert Storm, People Liberation Army, R-27, RAF Nimrod, RSAF, S-400 missiles, Sea King, SEAD, Sukhoi, Sukhoi PAK-FA, Sukhoi Su-33, surface-to-air missile, TALD, Tommahawk missiles, U.S Marines, US Department of Defense, US Navy, USMC, USS Kitty Hawk, Vietnam War, Wild Weasels

Boeing A160 – VTOL UAVs Comes to Age

FARNBOROUGH 2010: Boeing A160 Hummingbird

Farnborough 2010 (July.10) Boeing – A US aerospace company’s massive showing, included its own unmanned air vehicle pavilion. With an 11m (36ft) rotor diameter nearly as wide as the 10.7m autonomous helicopter is long, it is larger than other vertical take-off UAVs. But weighing in at 1,135kg (2,500lb), with its largely composite frame, it is also lighter, making up for the fact that it carries 45kg more than its weight in fuel. However, what makes the A160 unique is not something visible in its low-drag, reduced radar profile silhouette.

In conventional helicopters, the revolutions per minute of the rotors is normally locked in for a maximum forward speed, given weight and altitude considerations. At maximum forward speed, the tip of the advancing blade moves at speeds slightly under Mach 1, avoiding the drag and vibration seen at higher speeds. But being locked into a constant maximum rotor RPM also means that anything less that maximum forward speed – a hover, low-speed forward flight – the rotor is moving far faster than actually necessary, wasting fuel and creating drag, shortening the helicopter’s range. Humming Bird so far managed to fly at the speed of 165kt (305km/h) – with a service ceiling of between 20,000ft and 30,000ft and a range of around 2,500nm (4,620km). It is its blades that makes it unique, for range and speed compared to other in its class. For A160, the stiffness and cross-section of the rotor blades vary along their length. The low-loading hingeless design allows for changing RPMs to optimise efficiency at different speeds and altitudes. The Hummingbird has come a long way since the diesel-powered, variable-speed rotor experiment that was awarded a 30-month technology demonstration contract in March 1998. The first true Hummingbird prototype, a three-bladed design, debuted in December 2001 and had its first forward flight the following month at former US Air Force base at Victorville, California, using a Subaru engine.

In September 2003, DARPA awarded Frontier a $75 million contract for the design, development and testing of four A160s. By May 2004, Boeing had purchased Frontier from Karem. In August 2005, Frontier Systems – now a Boeing subsidiary – received a $50 million contract from the Naval Air Warfare Center Aircraft Division to examine the affordability of long-range VTOL UAVs for payload delivery. With no orders on the books, Boeing made the decision in late 2009 to put the helicopter into production, an unusual move in a business where manufacturers usually wait for a contract award or at least a military requirement before opening production. The A160 has already demonstrated its ISR capabilities to the US Army, as far back as 2008, at an annual C4ISR exercise at Fort Dix in New Jersey. Operating at the army’s Class IV UAV for the exercise, the Hummingbird integrated five different payloads for the event, Lavoranda says, including a 380mm (15in) Wescam electro-optical/infrared sensor ball and two mini tactical common datalink transceivers used to downlink full motion video from the EO/IR sensor Rover terminals to both mounted and dismounted troops with Rover terminals. The Hummingbird also proved its role as a communications relay, keeping two Humvees in contact when they moved out of the line of sight. In March, during six flights in two days, the A160 demonstrated its autonomous cargo delivery capabilities to the Marines, Wattam says, consistently delivering sling-loaded cargo within 1.2m of the target drop site. Furthermore, the A160’s proprietary, portable ground control system makes it possible to deliver cargo without a trained UAV pilot at the delivery site. After the UAV flies its pre-planned route, it stops and orbits until someone at the forward delivery location instructs it, with the touch of a button, to proceed to the inbound delivery point. Once there, another click tells it to hover over the delivery point. Adjustments can be made within a 1km range of the original delivery site before instructing the Hummingbird to lower its load, release the cable and head home on its predetermined path.

Unmanned Cargo Resupply Contract

K-MAX unmanned aircraft

According to the Sources Lockheed, together with manufacturer Kaman Aerospace, will get $45.8 million to operate the K-Max – who is copable of carrying 2721.6kg (6,000lbs) of cargo at sea level and more than 1,814.3kg (4,000lbs) at 10,000ft – while Boeing will receive $29.2 million to use its A160T Hummingbird to deliver cargo to Marines in Afghanistan. The Hummingbird, designated the YMQ-18A by the Pentagon, with its patented adjustable rotor speed technology, holds the record for endurance in its class, at 18.7h. In August 2010 the A160T Hummingbird underwent jungle test flights in Belize to test the ability of DARPA FORESTER foliage-penetrating radar to penetrate jungle cover. What makes this UAV unique is the incorporation of many new technologies – such as advance composite materials, Optimum Speed technology, ability to shift to another gear, and finally fthe uselage’s two large, stiff monocoque skins which help keep the frequency ranges of the structure outside the frequency ranges of the rotor as it changes its speeds.

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Filed under Afghanistan, Agusta Westland, ASN Technology, Attack helicopters, Boeing, Drone Technology, Drones, Flight Simulation, Global Aviation, Humming Bird, Information Operations, K-MAX, Predator, Radars, RQ-4 Global Hawk, U.S Drone Technology, U.S Marines, UAV, US Air Force, Vertical takeoff UAV

T-129: New Kid in a Block of Attack Helicopters

T-129 Attack Helicopter

Vey recently Turkey has increased its order for the T129 (shown above) attack helicopter to 60 aircraft, with prime contractor Turkish Aerospace Industries to deliver nine newly ordered examples by mid-2012. When I saw this machine first time, it reminded good old Apache. Is this rotorcraft the Apache for third world countries? Well I don’t know, they might look the same, but they are not same. I am writing this post to prove myself wrong. That T-129 is not cheaper Apache, but infact it has or will have its own place in the market of attack helicopters. Before I proceed I must remind you, that it is same 129 whose prototype crashed on the afternoon of 19 March during a test flight. Early indications point to a loss of power to the tail rotor while flying at an elevation of 1,500ft (455m) near Verbania in northern Italy. AgustaWestland is to make two T129 prototypes in Italy, after which manufacture will shift to its Turkish partner TAI. TAI general director Muharrem Dortkasli says the first T129 ATAK will be handed over to the Turkish armed forces in the third quarter of 2013. Turkey will be responsible for international marketing and sales of the design, and industry sources say several countries are already evaluating the product, including Jordan and Pakistan.

The T129 is a formidable, new, highly powerful and capable all-weather day and night multi-role attack helicopter which is being developed in cooperation by AgustaWestland, Aselsan and TAI (Turkish Aerospace Industries) for Turkey and other export markets. It is based upon the AW129 and its predecessor, the battle-proven A129 Mangusta platform. High weapon payload, excellent performance for ‘hot and high’ conditions and range and endurance of up to 3 hours are enabled by state-of-the-art LHTEC-T800 engines, making the T129 a critical multi-role resource for attack and deterrent operations. Low signature and agility ensure maximum stealth, and a significant weapons payload enable the T129 to operate in the most hostile of battlefield environments as well as in confined areas typical of current military scenarios. Latest technology features include Integrated Aircraft Survivability Equipment which delivers vital survivability tools and integrated mission management utilising an advanced FLIR sighting system, Helmet Mounted Display and Mission computers. High survivability enhanced by ballistic tolerance and crashworthiness is a fundamental design feature. The T129 benefits from the high field supportability necessary for an aircraft needing to operate in remote areas with the minimum logistical support.

Both helciopters resembles closely, however, AH-64’s (shown below) main rotor blade (BERP) is its distinguishing features, Unfortunatly T-129 offers half of Apache’s Maximum Takeoff Weight (with 5,000kg) compared to Apache’s 10,000kg. Another distinguishing feature is T-129’s 5 main rotor blades. The T-129 has several key improvements over the original A129 inline with the requirements of the Turkish Army. he T-129 will carry 12 Roketsan-developed UMTAS anti-tank missiles (Turkish indigenous development similar to Hellfire II) and it will use the more powerful LHTEC T800 (CTS800-4) engine.

Boeing AH-64D Apache Longbow

The AH-64 is designed to endure front-line environments and to operate during the day or night and in adverse weather using avionics, such as the Target Acquisition and Designation System, Pilot Night Vision System (TADS/PNVS), passive infrared countermeasures, GPS, and the IHADSS. The AH-64 is adaptable to numerous different roles within its context as Close Combat Attack (CCA), and has a customizable weapons loadout for the role desired.In addition to the 30-mm M230E1 Chain Gun, the Apache carries a range of external stores on its stub-wing pylons, typically a mixture of AGM-114 Hellfire anti-tank missiles, and Hydra 70 general-purpose unguided 70 mm (2.76 in) rockets.

Although both helicopters offers a capability to carry sidewinder and AIM-92 Stinger, what is missing from T-129 is Longbow Radar, what I consider a key to Apache operations. The lessons of the Gulf War, and the evolving battlefield air defence threat, created the context in which the digital AH-64D (Longbow Version) Apache was conceived. An optional fit to its baseline configuration is the Longbow weapon system, comprising the Northrop-Grumman (previously Westinghouse) AN/APG-78 Longbow mast mounted Fire Control Radar (FCR), and a Lockheed-Martin AN/APR-48 Radar Frequency Interferometer (RFI) package, both designed for all weather operation through precipitation and battlefield obscurants. The Longbow weapon system supports the AGM-114L active radar guided missile, operating in the same millimetric band as the radar.

T-129 A Kid about to born

The Longbow radar is a very low peak power, millimetric band system, with extremely low sidelobes by virtue of a very large relative antenna size. The low emitted power, extremely narrow pencil beam mainlobe, and undisclosed LPI modulation features provide a system with a range of the order of 10 km in clear conditions, which is near to undetectable by established RWR technology. Only a highly sensitive channelised ESM receiver with a high gain antenna and low noise receivers can reliably detect such a signal, under optimal antenna pointing conditions. The choice of millimetric band means that atmospheric water vapour and oxygen resonance losses rapidly soak up the signal, which is also out of the frequency band coverage of most RWRs. The radar will track up to 128 targets and prioritise the top 16. The radar employs both real beam mapping and Moving Target Indicator (MTI) techniques, to provide the automatic detection, tracking and non-cooperative identification of surface targets, with a secondary capability against low flying aircraft. Target identification algorithms in the radar’s software look at the shape of possible targets, and their Doppler signatures, to identify aircraft, helicopters, SPAAGs, SAM systems, tanks, AFVs, trucks and other wheeled vehicles. The capability exists to identify stationary targets through radar transparent camouflage netting and foliage. Real beam video and synthetic imagery can be displayed.

The provision of a highly automated weapon system with basic sensor fusion is unique at to the Apache Longbow, and provides clearly unprecedented lethality in comparison with helicopters using only thermal imaging sights and laser guided missiles. Such systems are limited to engaging one target at a time, unlike the Apache Longbow which can engage many targets concurrently. Howver I must mention here T-129’s advanced milimeter wave radar, claimed to be similar to Longbow and IAI/ELTA radars. Mast radar, similar to that of Apache Longbow but based on IAI/ELTA’s (Israel) surveillance and targeting radar with SAR and ISAR capability, has been added on the top of the rotor. The radar can identify land and sea targets from at least 30 kilometres. I am unsure about the technical details of T-129 radar, but there is something comparable to Longbow abilities is surprise to me.

Looking at the airbrone FLIR T-129 incorporates ASELFLIR-300T is a multi-sensor electro-optical targeting and surveillance system. ASELFLIR-300T fulfills multiple mission requirements including; Pilotage / Navigation, Surveillance, Target Search, Track, Locate and Designation. Having a flexible hardware and software design architecture, the system can be used on different platforms ranging from rotary, fixed wing and unmanned air vehicles to naval ships. Pilotage / Navigation, Surveillance, Target Search, Track, Locate and Designation. ASELFLIR-300T System includes a High Resolution Infra Red (IR) Camera, a Laser Rangefinder / Designator (LRF/D), a Laser Spot Tracker (LST), a Color TV Camera and a Color Spotter Camera. The system consists of the following Weapons Replaceable Assemblies (WRAs); Turret Unit (TU), Electronics Unit (EU), Hand Control Unit (HCU), Boresight Module (BSM).

Looking at the potential customers for T-129, it may serve well, but offers no near capabilities as Apache. With its enhanced Integrated Aircraft Survivebility Equipment, Adaptable and Asymmertic Weapon Load Capability, the rotorcraft does have a potential to become a successful machine and secure its position among world’s best attack helicopters.

Click Here for brochure of Atak Helicopter.

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Filed under Afghanistan, Agusta Westland, Apache AH-64, ATAK, Attack helicopters, Aviation, Boeing, Current Affairs, Engineering, Flight Global, Global Aviation, Longbow Radar, Milimeter Wave Radar, Pakistan, Paris Art Show, T-129, Turkey, Turkish Aerospace Industries