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Flying Wizards:

February 27, 2018

 

Electronic Warfare in the SAAFAs discussed last month, any modern air force which does not have a mastery of Electronic Warfare (EW) is placing its aircraft and air crew at huge risk, not only from peer competitors, but from rebel groups, insurgencies, and other non-state actors who are increasingly able to acquire modern communication tools and anti-aircraft missiles.

 

 

 

The South African Air Force (SAAF) entered the 1990s with the most advanced set of EW systems in Africa, maintained within a highly capable and efficient set of operational and analytical structures. This was the result of years of sustained investment into EW techniques and technologies, the creation from scratch of a local industry able to span the entire spectrum of EW capabilities, and the building of substantial testing, simulation and evaluation systems.

While not cheap, that investment was crucial for the SAAF and other arms of service to be able to continue operating in Angola during the last phase of the Border War, from the mid-1980s to 1989, where the combined Cuban and Angolan forces, with assistance from the then-USSR, had established one of the strongest air defence networks in the world. By war’s end, four different radar-guided and five different IR-guided surface-to-air missile (SAM) systems were deployed, along with a whole host of tracking and surveillance radars, and the latest export MiG-23Ms, carrying R-23 (AA-7) and R-60 (AA-8) air-to-air missiles.

As a result, the SAAF equipped itself with locally-made systems that spanned the EW spectrum, from aircraft self-protection systems including missile warning receivers and flare and chaff decoys, through to high-power stand off and escort jammers, and long-range SIGINT receivers.

Many of these capabilities remain in service and have received some upgrades, but they now require either replacement or substantial new investment if they are to handle the types of threats now being encountered in the SAAF’s areas of operations. What’s more, the SAAF lost the most important stand-off EW system in its arsenal when it retired its Boeing 707s in 2006.

This month we’ll look at the primary EW platforms in use in the SAAF; next month we’ll explore the self-protection systems installed on SAAF aircraft and what needs to be done to improve them. Later, we’ll look at the structures and organisations that support EW in South Africa and how they may be kept viable.

Understandably, both the SAAF and the various manufactures are unwilling to reveal details about the EW systems in operational use, or in some cases even acknowledge their existence. Some of the information below is being revealed publicly for the first time, but most of the details around the systems and their history remain secret.

However, to best understand where the SAAF stands and what it needs, it’s important to know what systems are in service. On the operational side, the SAAF’s primary EW platforms are the Mobile Ground SIGINT System, C-47TP EW, Oryx Radar Jammer (ORJ), Oryx Communications Jammer (OCJ), Gripen C/D EWS-39 onboard EW suite, and Super Lynx 300 Sea Raven ELINT/ESM system. Only the Gripen, Super Lynx, and an updated version of the ORJ have been recent additions.

As a brief refresher, EW is split into four main areas:

Electronic support (ES): formerly electromagnetic support measures (ESM), which encompasses the passive receiving and analysis of signals in real-time for tactical purposes.

Electronic attack (EA): formerly electromagnetic countermeasures (ECM), which encompasses both jamming and the use of decoys like chaff and flares.

Electronic protection (EP or EPM): formerly electromagnetic counter-countermeasures, which encompasses the design and operation of radars, missile seekers, etc. to counter the effects of EA/ECM.

Signals intelligence (SIGINT), which includes electronic intelligence (ELINT) to gather and analyse large amounts of signal data to determine the type, composition, location, and capabilities of enemy radio-emitting systems. This is used to build an electronic order of battle (EOB) and communications intelligence (COMINT) to intercept and listen into enemy communications. Both are hybrid online/offline approaches, in that while they can be used to support real-time operations, the main purpose is to store and later analyse raw data in detail to support intelligence operations. Modern ES systems, such as the Sea Raven, can record and store a substantial amount of raw signal data and thus have a secondary ELINT capability, but they’re not a substitute for dedicated ELINT platforms.

The Mobile Ground SIGINT System (MGSS) is a vehicle-borne ground-based intelligence-gathering system based around three components: The COMIX communications intelligence system from GEW, the RADIX ELINT system from Sysdel, and a set of radar-reflective balloons used to deceive enemy radar systems.

COMIX is a containerised system that fits on the back of a Samil truck, with another truck carrying the long-range HF/VHF/UHF intercepting antennas. The primary operator sits at a console that provides a spectrum waterfall display and other diagnostic and interception toolkits.

RADIX is a more portable solution, designed so that a small team can move it and deploy it nearer to enemy positions to collect all-important signals, particularly radar. It consists of a compact directional antenna, two control and processing boxes with built-in orange sunlight-readable displays, a power source, and a long reel of cable to allow operators to move the antenna some distance away from the rest of the system. Primarily meant to identify and locate radars, RADIX is able to perform frequency measurement and direction finding with a high probability of intercept off a single pulse.

The radar-reflective balloons are useful decoys able to match the radar cross-section signatures of a number of SAAF aircraft through the careful shaping of a metallic structure inside a helium-filled balloon. Although only a static decoy, in that the balloons can’t mimic the moving components of a helicopter or a real aircraft’s movements, the balloons are able to introduce substantial confusion into older air defence systems and slow down reaction times. When first used operationally in Angola in the 1980s, one balloon barrage reportedly attracted eleven surface-to-air missile launches as the air defence operators mistook them for SAAF helicopters.

Amusingly, three of the balloons were once an unintentional decoy when they were accidentally released from a SAAF base near Pretoria just before dawn one morning a few years ago. Blown around by the winds and with the rising sun reflecting in unusual patterns on the complex metallic structures inside, the twinkling orbs of light caused a host of UFO sightings. The SAAF, at the time, wishing to keep the existence of the balloons secret, denied all knowledge of the objects.

In total, a full MGSS deployment will require between six and ten qualified EW operators and can span up to ten vehicles.

A single C-47TP, serial 6828, was converted in the early 1990s to serve as an airborne training platform for EW operators who were to transition onto other platforms, such as the EW-fitted Boeing 707s then in service with the SAAF. A bank of integrated consoles fills up the starboard side of the fuselage, with stations for seven EW operators. The left-most consoles are dedicated to the MANTIS ELINT system manufactured by Sysdel, while the right-most consoles are for the DACIS (Dakota Communications Intelligence) COMINT suite from GEW. Unfortunately, very little is known about the capabilities of either of these systems.

Despite the retirement of the 707s, the C-47TP EW has not replaced it as an operational platform, largely because of its limited range and relative vulnerability. This aircraft was also an early victim of the control cable corrosion issue affecting the SAAF’s C-47TPs and has not flown for some months. If funding remains as low as it has been for the past few years, it may never fly again.

The Oryx Communications Jammer (OCJ) is a palletised stand-off communications system jammer based on the GEW (then Grintek) GSY-1500. The system is designed to work over the 20-500 MHz frequencies, with an interception range of over 450 km and can demodulate both AM and FM transmissions. The receiver is linked to a large fold-away dipole log-periodic antenna projecting from the starboard door, and the system is controlled by a single EW operator in the back of the aircraft.

In the jamming role the GSY1500 can be set for up to 20 separate targets, using time- or frequency-divided multiplexed output to jam them all in sequence. To detect target transmitters to support jamming, the GSY1500 has a secondary ES and COMINT capability and can be used in that role if necessary. To avoid the need for permanent modifications to the Oryx helicopter, the OCJ system is a self-contained roll-on/roll-off solution and leaves no trace on the aircraft when removed.

The Oryx Radar Jammer (OCJ) is a Sysdel-developed palletised counter-radar multi-band jammer. It consists of two large flat phased array antennas mounted in the main cabin on air-cushioned bearings, allowing them to swivel across a 110º arc on either side of the helicopter.

To allow for all-weather operation, the helicopter doors are replaced with special RF-transparent radome doors, the first of their kind in the world. An omni-directional ES antenna is on a mechanically-retractable mount underneath the rear fuselage. The rear of the cabin contains a console for two operators, letting one operate and analyse the ES signals while the other reacts accordingly with the jammers.

Substantial challenges were overcome in providing a radiation-safe environment inside the helicopter while retaining transmitter effectiveness, and the system is self-contained and takes only 30 minutes to install in (or remove from) an operational Oryx. No permanent modifications are required so there’s no impact on its operational capability and no alteration of flight dynamics.

The primary transmitter array operates in the D-band (1-2 GHz) with the secondary array operating simultaneously in the E/F-band (2-4 GHz), covering most air defence and tracking radars encountered in sub-Saharan Africa. The system has a digital radio frequency memory (DRFM) mode for coherent radars in addition to more traditional noise jamming approaches.

The OCJ system later received an unspecified set of upgrades under Project Deer.

By far the most potent single EW system in the SAAF’s inventory is the internal EW system on the Gripen C and D operated by 2 Squadron at AFB Makhado. EWS-39, as the system is called, not only features a full ES suite and a powerful on-board jammer, but includes some parts developed by Avitronics (now Saab Avitronics) as part of an agreement made with the then-Celsius Tech in the mid-1990s.

EWS-39 is capable of operating as a DRFM jammer for coherent radars, as a noise jammer, or as a continuous wave doppler radar, and can transmit simultaneously from the Forward Transmitter Unit and Forward Antenna Unit at the front of the aircraft and the Fin Pod Unit and Rear Antenna Array mounted on the vertical fin. As with most DRFM radars, it is capable of ‘ghosting’ and similar countermeasures.

The four Super Lynx 300 shipboard helicopters in service with 22 Squadron at AFB Ysterplaat have been fitted with the impressive Sea Raven ESM and ELINT system from Sysdel. The system can geolocate, categorise, and identify any radio signal in seconds over a radius of a few hundred kilometres, often based on a single received pulse.

It does this by carrying four traditional amplitude comparison direction-finding spiral antennas, which determine direction by measuring the gain difference, and two interferometer antennas (the flat rectangles on either side of the Super Lynx’s nose) that measure the phase differences of signals received by the separated antennas.

Sea Raven’s onboard computer then does the complex work of combining and correlating the input received from all six antennas to create an accurate direction-finding line of bearing, as well as de-interleaving the incoming signal(s), determining characteristics like frequency, pulse width, modulation type (if any), and attempting to match it to its internal threat library and parameter database.

As additional pulses are received, the computer links them all up and adds inter-pulse data like pulse repetition intervals, frequency shifts, intra-pulse modulation changes, as they become available, to create a more complete model and a more accurate match to the parameters in its onboard databases. If the Super Lynx is moving, it can also triangulate the calculated lines of bearing into exact co-ordinates, rapidly creating a complete electronic order of battle (EOB).

All positional and type data calculated by Sea Raven is displayed to the air crew via a control display unit, with a central control pad flanked by two 3ATI monochrome thin-film electroluminescent displays sourced from Aktelux.

Like EWS-39, the Sea Raven system can store a substantial number of signals in its onboard storage for later downloading and analysis. This is what gives both systems their secondary ELINT capability.

Clearly, all of these platforms possess a high level of capability and with competent operators are able to achieve excellent effects, but the field of EW never sits still, and constant upgrading and replacement is necessary if the SAAF is to remain competitive.

Next month we’ll take a deeper look at the on-board counter-missile self-protection systems on SAAF aircraft.

 

If you would like to comment, please contact Darren Olivier on dolivier@africandefence.net.

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