Delfin
Forista Sancionado o Expulsado
No pensemos en el lanzamiento de "una" Dardos II... sino en un ataque de saturación. Si el objetivo es tan valioso como para justificar el uso de bombas guiadas... también justifica el lanzamiento de variassssss
The HdH JDAM-ER effort builds on the DTSO GTV/Kerkanya glidebomb effort, using the standard JDAM tailkit with suitable software alterations. With a standoff range likely to be well in excess of 50 NMI, the JDAM-ER will revolutionise much of the bombing game. The weapon will be suitable for medium/high altitude drops, and low level toss deliveries, placing the bomber outside the range of most air defence weapons (Author).
Like all other variants of the JDAM, the JDAM-ER will permit massed attacks against prebriefed targets. A fighter could pickle off an arbitary number of these weapons, and turn tail while the bombs each autonomously fly to their targets. Even with a 50 NMI glide range, the footprint the fighter can hold at risk encompasses roughly a 100 NMI circle. A key issue for the RAAF will be achieving a mature Mil-Std-1760 capability on its F-111C/G and F/A-18A fleets before the weapon becomes available.
Exploiting the full potential of the JDAM-ER, especially the 500 lb GBU-38 varianant, will require smart bomb rack technology, with a Mil-Std-1760 capability on each ejector. For the F/A-18A this would require a dual or triple rack, for the F-111C/G a modified BRU-3/A six hardpoint rack. The GBU-38/JDAM-ER would be especially well suited to the F-111C/G as with four 6 hardpoint smart racks it has to potential to engage 20-24 aimpoints on a single pass, subject to clearances. Autonomous targeting of the JDAM-ER will require either a good Synthetic Aperture Radar or a high resolution thermal imager with exceptional jitter performance. The latter makes a good case for some technology insertion into the Pave Tack, since no existing thermal imaging pods come near the required performance (doubters might consider looking up the jitter specifications of such if they choose not to believe this author).
The DARPA AMSTE program recently demonstrated a successful strike against a moving target using a JTIDS datalink aided JDAM. The target was tracked by two separate airborne GMTI radars, providing a continuous stream of target coordinates which were fused and then tranmitted over a JTIDS channel to the JDAM in flight. The weapon is reported to have impacted within the lethal radius of the target (Author).
Datalink Guided JDAMs
The limitation of the baseline JDAM guidance package is that it was designed to engage fixed targets, the original intent being to fit precision seekers for attacking moving targets. More recent developments in the US suggest that a radical change may be afoot in this area.
The Affordable Moving Surface Target Engagement (AMSTE) technology demonstration program is a complex effort which is intended to develop and prove techniques for the engagement of moving ground targets, using cheap munitions and standoff radar targeting techniques. In particular, AMSTE is exploring Ground Moving Target Indicator (GMTI) radar techniques, target position refinement using information from multiple radars on multiple aircraft, and the use of datalinks to guided weapons.
Perhaps the most dramatic outcome of the AMSTE effort was the August 22, 2002 demonstration, in which a JDAM modified with a JTIDS datalink receiver successfully engaged a moving vehicle in a column, using target coordinates produced by a distant E-8 JSTARS and a second radar on an airborne testbed.
The inert JDAM was dropped by an F-16C at 20,000 ft, the target was part of a vehicular column travelling at 30 km/h. Once released, the JDAM acquired the JTIDS signal and continuously updated its aimpoint position as it flew toward the target. DARPA have not disclosed the frequency of updates, but it is likely that a whole JTIDS net was reserved for this purpose.
The AMSTE demonstration is important since it proves the feasibility of continuosly datalinking a moving target's position to a JDAM in flight. The position information could be produced a GMTI radar on a distant aircraft, be it a fighter with a larger radar, an ISR platform or a UAV, or it could be produced by a FLIR/EO/laser targeting system on a fighter or an endurance UAV such as a Predator or a Global Hawk. Once the targeting sensor is measuring the location of the target vehicle, it takes little effort to pump this information out on a datalink radio channel to a bomb in flight.
Handling the target coordinates at the bomb end is perhaps the most challenging aspect of such systems. The guidance software will have to incorporate a Kalman filter which estimates the position of the target vehicle based upon a track history of continuously transmitted coordinates. A prediction of the target's position based on this data is then used to adjust the bomb's aimpoint. Since the JDAM is flying blind toward its target, the quality of the prediction algorithms is critical to success.
Another important aspect of seekerless JDAM engagement of moving targets is the accuracy of the transmitted coordinates, since these are added to the JDAM's guidance error. While many radars support GMTI techniques, very few support the more accurate multi segment Differential Phase Centre Antenna (DPCA) techniques, as these require specific adaptations to the radar antenna design, and feed designs. As a result, the range and bearing accuracy of GMTI radars usually does not match that achieved in SARs. The AMSTE program works around this limitation by fusing GMTI tracks from multiple airborne radars, to yield a best estimate of target position. The target bearing error can be modest, and triangulation of the target using bearings from two or more radars separated by several miles evidently makes the difference.
When the AMSTE derived technique does eventually become operational, it will permit the concurrent engagement of multiple ground vehicles in all weather day/night conditions. Whilst it may not match the accuracy of seeker equipped JDAMs, it makes up for that limitation in much lower weapon costs.
Combining a datalink midcourse system with a cheap autonomous short range seeker, such as a device derived from an anti-armour submunition, of course yields the best of both worlds.
What is clearly evident is that the sanctuary of motion will not last long for evaders of the JDAM.
Fuente: http://www.ausairpower.net/TE-JDAMPt1.html
The HdH JDAM-ER effort builds on the DTSO GTV/Kerkanya glidebomb effort, using the standard JDAM tailkit with suitable software alterations. With a standoff range likely to be well in excess of 50 NMI, the JDAM-ER will revolutionise much of the bombing game. The weapon will be suitable for medium/high altitude drops, and low level toss deliveries, placing the bomber outside the range of most air defence weapons (Author).
Like all other variants of the JDAM, the JDAM-ER will permit massed attacks against prebriefed targets. A fighter could pickle off an arbitary number of these weapons, and turn tail while the bombs each autonomously fly to their targets. Even with a 50 NMI glide range, the footprint the fighter can hold at risk encompasses roughly a 100 NMI circle. A key issue for the RAAF will be achieving a mature Mil-Std-1760 capability on its F-111C/G and F/A-18A fleets before the weapon becomes available.
Exploiting the full potential of the JDAM-ER, especially the 500 lb GBU-38 varianant, will require smart bomb rack technology, with a Mil-Std-1760 capability on each ejector. For the F/A-18A this would require a dual or triple rack, for the F-111C/G a modified BRU-3/A six hardpoint rack. The GBU-38/JDAM-ER would be especially well suited to the F-111C/G as with four 6 hardpoint smart racks it has to potential to engage 20-24 aimpoints on a single pass, subject to clearances. Autonomous targeting of the JDAM-ER will require either a good Synthetic Aperture Radar or a high resolution thermal imager with exceptional jitter performance. The latter makes a good case for some technology insertion into the Pave Tack, since no existing thermal imaging pods come near the required performance (doubters might consider looking up the jitter specifications of such if they choose not to believe this author).
The DARPA AMSTE program recently demonstrated a successful strike against a moving target using a JTIDS datalink aided JDAM. The target was tracked by two separate airborne GMTI radars, providing a continuous stream of target coordinates which were fused and then tranmitted over a JTIDS channel to the JDAM in flight. The weapon is reported to have impacted within the lethal radius of the target (Author).
Datalink Guided JDAMs
The limitation of the baseline JDAM guidance package is that it was designed to engage fixed targets, the original intent being to fit precision seekers for attacking moving targets. More recent developments in the US suggest that a radical change may be afoot in this area.
The Affordable Moving Surface Target Engagement (AMSTE) technology demonstration program is a complex effort which is intended to develop and prove techniques for the engagement of moving ground targets, using cheap munitions and standoff radar targeting techniques. In particular, AMSTE is exploring Ground Moving Target Indicator (GMTI) radar techniques, target position refinement using information from multiple radars on multiple aircraft, and the use of datalinks to guided weapons.
Perhaps the most dramatic outcome of the AMSTE effort was the August 22, 2002 demonstration, in which a JDAM modified with a JTIDS datalink receiver successfully engaged a moving vehicle in a column, using target coordinates produced by a distant E-8 JSTARS and a second radar on an airborne testbed.
The inert JDAM was dropped by an F-16C at 20,000 ft, the target was part of a vehicular column travelling at 30 km/h. Once released, the JDAM acquired the JTIDS signal and continuously updated its aimpoint position as it flew toward the target. DARPA have not disclosed the frequency of updates, but it is likely that a whole JTIDS net was reserved for this purpose.
The AMSTE demonstration is important since it proves the feasibility of continuosly datalinking a moving target's position to a JDAM in flight. The position information could be produced a GMTI radar on a distant aircraft, be it a fighter with a larger radar, an ISR platform or a UAV, or it could be produced by a FLIR/EO/laser targeting system on a fighter or an endurance UAV such as a Predator or a Global Hawk. Once the targeting sensor is measuring the location of the target vehicle, it takes little effort to pump this information out on a datalink radio channel to a bomb in flight.
Handling the target coordinates at the bomb end is perhaps the most challenging aspect of such systems. The guidance software will have to incorporate a Kalman filter which estimates the position of the target vehicle based upon a track history of continuously transmitted coordinates. A prediction of the target's position based on this data is then used to adjust the bomb's aimpoint. Since the JDAM is flying blind toward its target, the quality of the prediction algorithms is critical to success.
Another important aspect of seekerless JDAM engagement of moving targets is the accuracy of the transmitted coordinates, since these are added to the JDAM's guidance error. While many radars support GMTI techniques, very few support the more accurate multi segment Differential Phase Centre Antenna (DPCA) techniques, as these require specific adaptations to the radar antenna design, and feed designs. As a result, the range and bearing accuracy of GMTI radars usually does not match that achieved in SARs. The AMSTE program works around this limitation by fusing GMTI tracks from multiple airborne radars, to yield a best estimate of target position. The target bearing error can be modest, and triangulation of the target using bearings from two or more radars separated by several miles evidently makes the difference.
When the AMSTE derived technique does eventually become operational, it will permit the concurrent engagement of multiple ground vehicles in all weather day/night conditions. Whilst it may not match the accuracy of seeker equipped JDAMs, it makes up for that limitation in much lower weapon costs.
Combining a datalink midcourse system with a cheap autonomous short range seeker, such as a device derived from an anti-armour submunition, of course yields the best of both worlds.
What is clearly evident is that the sanctuary of motion will not last long for evaders of the JDAM.
Fuente: http://www.ausairpower.net/TE-JDAMPt1.html
