Rafale F4 Standard
As part of a spiral development, the MoD and Dassault Aviation recently announced the launch of Standard F4, the next major step for the Rafale programme. The Rafale was conceived from the outset with ‘evolutivity’ in mind, and its weapon system is designed in such a way as to facilitate upgrades. The Standard F4 development strategy is based on four pillars that cover interconnectivity, combat engagement/sensors, armament upgrades, and support/availability. Formal development of the new Standard F4 will begin in 2018, but risk-reduction studies will be launched this year.
“Standard F4 will be even more ambitious than F3R,” explained the programme director. “While F3R is mainly restricted to software upgrades, new hardware will be required for the far-reaching F4, even though the airframe will remain unchanged. In practice, F4 will be split into F4.1, for older, in-service aircraft, and F4.2, for new-build airframes. F4.1 will be limited to a number of improvements only in order to avoid complex hardware changes, but F4.1 will accept the new Rafale weapons now being developed. F4.2 will include the whole package of upgrades for the radar, the electronic warfare suite, the Front Sector Optronics and the cockpit to accommodate a helmet-mounted display (HMD).
“All Tranche 4 aircraft – the 28 airframes to be delivered in 2021-23, and all Tranche 5 Rafales will be delivered as F4.2 aircraft. Standard F4 development will take about six years, with service entry due in 2025, but some systems will find their way into the inventory earlier, as soon as they are ready, using a building-block approach thanks to software upgrades.”
Communications advances
With the advent of the F4 Standard, the Rafale will be equipped with the new Thales Contact software radios that will be widely fielded across the French Armed Forces in the next couple of years. These new-generation radios will remain fully compatible with legacy radio waves and should be tested on the Rafale as early as 2020.
The Rafale will also be fitted with a new point-to-point, directional, discreet, high-speed fighter data link to be used exclusively for communications and data exchange within a Rafale patrol. This will use a new three-dimensional waveform (FO3D, or Forme d’Onde 3 Dimensions) generated by digital signal processing using dedicated antennas for the required bandwidths and the expected data flow. This new fighter data link will supplement – and not replace – the current Link 16. Accordingly, the Rafale’s core avionics system will have to be modified to accommodate the two data link systems that will operate alongside each other (although they will not be linked).
The architecture of the internal network will have to be modified for it to become even more resistant to cyber attack. The CAPOEIRA (Connectivité Améliorée Pour les Evolutions du Rafale, or improved connectivity for the Rafale’s future variants) research programme has recently been launched to help determine what sort of architecture will be required for a future, totally secure navigation and attack system. In 2015, as part of an urgent operational requirement, the French Air Warfare Centre integrated a satellite communication (satcom) system into the Rafale. “This system will not be kept on the Rafale,” the programme director added. “The future military satcom will be encrypted, fully secure and impossible to intercept thanks to a military-grade antenna and a hardened modem. It will enable the Rafale to activate a communication relay mode between fighters and troops on the ground on one side, and higher echelons on the other.”
Radar and Spectra upgrades
The current Thales RBE2 AESA radar will be further improved. It will benefit from the introduction of two new air-tosurface modes: a ground moving target indicator (GMTI), to detect and track moving targets over land, and a UHR (ultra high resolution) mode, to replace the current HR functionality for synthetic aperture radar (SAR) imagery, offering superior radar image quality at very long distances. The ability to interleave radar modes will be enhanced, thus helping provide aircrews with even better situational awareness.
The Spectra electronic warfare/selfprotection suite produced by Thales and MBDA is fully integrated. It is composed of a wide range of systems: a Détecteur d’Alerte Radar (DAR, or radar warning receiver), a Détecteur d’Alerte Laser (DAL, or laser warner), a Détecteur de Départ Missile (DDM or DDM NG, or missile launch detector), a high-power radar jammer, and decoy dispensers that can launch a range of flares and chaff.
Over the coming months, Spectra will be improved, with bandwidth extensions for the detectors and jammers to cover lower and higher frequency bands, thus providing an instantaneous reaction against any type of pop-up threat. “Our objective here is to obtain extremely accurate RF emitter geolocation and 3D tracking, including of airborne radars,” said the programme director. “The capabilities of a single Rafale to locate and track a threat without resorting to traditional, but timeconsuming, methods of triangulation or of bearing measurements along the aircraft’s flight path will be significantly improved. It is a very important step forward, and the recent progresses made by Spectra will boost the capabilities of the Rafale in that field.”
Advanced weaponry
New variants of current weapons will be modernised for the updated Rafale, including the Scalp cruise missile, the Mica air-toair missile and the Hammer (Highly Agile Modular Munition Extended Range) precision weapon. The new weapons will be introduced incrementally, through software upgrades. In February 2017 it was announced that the British and the French defence ministries had signed contracts with MBDA to upgrade the remaining Scalp/Storm Shadow stealth cruise missiles in service on both sides of the Channel.
Under the deal, MBDA will refurbish the missiles and carry out a limited upgrade to sustain the weapon until its planned out-of-service date in the early 2030s. The first refurbished Scalp missile is due to be delivered back to the French Armed Forces in 2020. Scalp cruise missiles were first fired in combat from Rafales during the conflict in Libya, in 2011. The missile has also been successfully used operationally in Iraq and Syria. The Mica family of AAMs, which includes the infrared-guided Mica IR and the radarguided Mica EM, will be updated to Mica NG (New Generation) standard with, among other undisclosed systems, new seekers.
The MBDA Mica, which equips the Mirage 2000-5, the Mirage 2000-9, the Rafale and upgraded Mirage F1s, has met with considerable success. Moreover, a surface-to-air version, the Vertical Launch Mica (VL Mica), has been ordered by several foreign nations. Expanded Hammer family The Hammer family will be expanded, minimising the need to procure Paveway II/ III and Enhanced Paveway precision-guided bombs from the United States.
Three variants of the Safran Electronics & Defense Hammer precision weapon are in service: the SBU-38, with inertial/GPS guidance; the SBU-64, with a dual-mode inertial/GPS and infrared seeker; and the SBU-54, with laser guidance as well as the inertial/GPS kit. “We need to increase our stocks of precision weapons and we are committed to helping promote and support a national weapons industry,” the programme director stated. “A new, simplified Hammer variant is already being developed. This Block 4 variant will be fitted with a revised rear kit, without the rocket motor. The wings will be retained, and its aerodynamic shape and its weight and balance will remain unchanged to ease aeromechanical integration onto the Rafale.
Recent operational experience has proved that the rocket motor is not always required, and not always switched on in combat by French aircrews, especially for short-range engagements during close air support missions. In any case, we will retain the capability to produce both variants of the Hammer, the powered variant remaining available for stand-off attacks in high-threat environments. “Other improvements are high on the agenda, including a data link between the weapon and the Rafale, and new seekers to engage other types of targets, including fastmoving, highly mobile vehicles.
We have launched preliminary studies to develop heavier variants of the Hammer to eventually replace the current inventory of 500kg-class GBU-16 Paveway II and 1,000kg-class GBU- 24 Paveway III laser-guided bombs. “Priority is likely to be given to the 1,000kg variant. A new rear kit will probably have to be designed, but every effort will be made to keep changes to an absolute minimum, most current components being reused, including the seekers and guidance systems.” A new, dual-mode seeker was exhibited by Safran at the Paris Air Show in June 2015.
GaN technology
Thales and the DGA are actively preparing the future radar developments that will be introduced on Standard F4.2, incorporating cutting-edge Gallium Nitride (GaN) technology for the radar and jammer antennas. Thanks to additional radar apertures, detection capabilities will be unmatched and electronic attack capabilities will become a reality. The programme director explained: “Even though we are entirely satisfied with the current RBE2 AESA radar, we are already working on the next generation scheduled to appear on new-build aircraft in 2025. “For the same volume, GaN technology will offer an expanded bandwidth, more radiated power and an even easier ability to switch from one mode to another, or from one functionality to another.
With the same antenna, we will be capable of generating combined, interleaved radar, jamming and electronic warfare modes as part of an electronic attack mission. “GaN emitters will not be restricted to the radar and they will also equip the Spectra suite. For example, for the antennas in the wing apexes, ahead of the canard foreplanes, we could obtain a very quick emission/reception cycle, either saving some volume or augmenting radiated power. On Tranche 5 Rafales, we will have at our disposal twice the amount of transmitted power for the radar and jamming antennas. Thales has already produced and tested in laboratories a series of GaN module prototypes for the new radar and initial testing results look extremely promising. “Following the entry into service of the AESA in 2013, the deliveries of the Meteor in 2018 will push the Rafale into a class of its own – we will be the only ones in the world operating a fighter equipped with an AESA and a ramjet-propelled missile – but we have to keep investing to maintain our leadership.
This is the reason why this GaN technological path is so important, especially for the development of additional emitting panels and apertures that will offer extended radar angular coverage. “It is not just an improvement; it is a real technological breakthrough in the field of detection. Jamming modes will not be left untouched and will push the Rafale’s electronic warfare capabilities to unprecedented levels thanks to the introduction of what we call ‘smart jamming’, with a wider band coverage and GaN emitters from 2025. These capabilities will be further expanded thanks to the adoption of MFAs [Multi-Function Arrays].” The Rafale’s Front Sector Optronics (FSO) will be fitted with a new-generation infrared search and track (IRST) sensor optimised for the tracking of air targets, either alone, or in conjunction with the RBE2 radar.
Changes in the cockpit
Although the Rafale’s man-machine interface is lauded by pilots, its cockpit will not be left untouched, with new, larger, lateral touchscreens to be adopted. Because the existing working environment is well balanced, with ergonomics that have proved to be highly successful, the DGA and the industry will introduce only minor adjustments in the cockpit’s design, as part of an evolutionary process.
More importantly, a Helmet-Mounted Display (HMD) will find its way onto the Rafale, filling an operational gap: “The DGA has formally expressed a need in order for the industry to study our requirements. Our specifications are fully compatible with various systems from different providers. We have taken steps to ensure that all Mk16F ejection seats produced under licence in France by SEMMB [Société d’Exploitation des Matériels Martin-Baker, a 50/50 joint venture between Safran and Martin-Baker] since 2015 are capable of accommodating an HMD.”
Long-term future
Safran Military Engines constantly innovates and further develops the M88 turbofan. The programme director admitted: “Contrary to popular views, we are not going to create a new M88 variant rated at 9 tonnes/20,000lb of thrust, nor a new high-pressure core. Nevertheless, modifications to the engine calculator will help further improve component durability and engine availability. M88 technology will gradually evolve in order to propel UCAVs [unmanned combat aerial vehicles], and the Rafale will eventually benefit from these technological advances, but not until the advent of the MLU [midlife upgrade] variant.” Future Rafale variants will benefit from the multiple research programmes launched by the DGA.
These include the extremely secretive DEDIRA (Démonstrateur de Discrétion du Rafale, Rafale discretion demonstrator), which focuses on new and innovative processes to improve the airframe’s lowobservable qualities against air-defence radars and fighter air-intercept radars. “We are currently having discussions with the Armée de l’Air and the Marine Nationale regarding their future operational needs and requirements,” the programme director confirmed. “Many options are being scrutinised, from the development of a UCAV to an increase in the number of Rafales.
Nothing has been decided yet. What I can tell you is that we will not alter the Rafale’s airframe if we do not need to and that we will keep its proven aerodynamic shape. “The Rafale retains a huge growth potential, especially regarding the size of the radar antennas and the dimensions and weighs of its weapons. We might adopt radar cross-section reduction kits, but without radically modifying the airframe. We will keep all options open.
For example, we are considering the possibility of increasing the number of decoys carried by the fighter. In this respect, a DIRCM [directional infrared countermeasures] turret used to generate a laser jamming signal to defeat an incoming missile could well find its way onto the Rafale.”
With such a clear roadmap ahead and with the recent successes on the export market, the Rafale’s long-term future is assured. Dassault Aviation and its partners are constantly investing to make sure their fighter remains at the forefront of technology. The future upgrades to be implemented on the Rafale are ambitious and far-reaching. They represent a clear technological breakthrough in several fields, utilising a fully mature, combatproven airframe that offers a considerable growth potential.