Robert Hewson Jane's Air-Launched Weapons Editor
London
The Royal Australian Air Force (RAAF) has made the first ever lock-on-after-launch (LOAL) firing of an MBDA Advanced Short-Range Air-to-Air Missile (ASRAAM).
The test was carried out in October 2008 but only announced by MBDA on 5 March. The company says it was the first time any in-service infrared (IR) guided missile has been successfully fired at a target behind the wing-line of the shooter - although several other manufacturers might dispute this.
According to an MBDA statement the firing was conducted from an F/A-18, at low level and "typical fighter speed", at a target located behind the fighter at a range of more than 5 km. The result was a direct hit on a target drone.
Short-range LOAL engagements are typically undertaken with targeting data from a pilot's helmet-mounted display (HMD), which allows a target anywhere within the field of view to be designated. Australia's upgraded Hornets are equipped with HMDs but the October test was carried out using offboard sensor data supplied by a second F/A-18 via its Link 16 datalink.
"A 'simple' helmet shot is less impressive these days," one programme official told Jane's . "The RAAF firing shows how you'd want to use the missile for real, using data fusion and 360-degree sensor coverage for targeting. It doesn't matter if the target is in the forward or rear hemisphere; the missile is capable of flying to any point, from which the seeker goes active. ASRAAM's incredible speed gets the missile looking into the right place as quickly as possible. The seeker already has a ±90° off boresight capability and reaches a very high angle of attack in flight so there's only a short gap between launch and when missile can see into the 'blind space' behind the launch aircraft."
The Australian engagement was described as "a simulated 'chase down' situation by an enemy fighter". MBDA said: "If the target was behind and above, the ASRAAM would follow the best trajectory based on the available target data. In that situation it would come off the rail, reach the safety point where the fins unlock, and then go back over the top of the launch aircraft."
ASRAAM's LOAL capabilities will be crucial for its future integration with the Lockheed Martin F-35 Lightning II Joint Strike Fighter (JSF). The ASRAAM is scheduled for fielding as part of the JSF's Block 3 configuration, with two internal missiles and the option to carry two externally on a new stealthy pylon. It will be particularly important for the JSF to use passive targeting for weapons like ASRAAM to avoid emissions from its own radar.
The external ASRAAM configuration is now under contract, with test assets delivered to Lockheed Martin. Fit, form and function integration testing is expected to start in April/May.
It has always been a credo of the JSF designers that an aircraft with an external payload cannot be stealthy. However, with ASRAAM, Jane's was told: "It's all a question of conops [concept-of-operations] and how much RCS [radar cross-section] you are prepared to trade off. If you need absolute stealth then you go buttoned up with two air-to-air missiles, but most missions won't demand that. This airplane is not invisible. If you look for it across enough wavelengths or in the IR spectrum you will find it, and if that happens you need to be able to fight your way out."
[SIZE=-1]© 2009 Jane's Information Group[/SIZE]
London
The Royal Australian Air Force (RAAF) has made the first ever lock-on-after-launch (LOAL) firing of an MBDA Advanced Short-Range Air-to-Air Missile (ASRAAM).
The test was carried out in October 2008 but only announced by MBDA on 5 March. The company says it was the first time any in-service infrared (IR) guided missile has been successfully fired at a target behind the wing-line of the shooter - although several other manufacturers might dispute this.
According to an MBDA statement the firing was conducted from an F/A-18, at low level and "typical fighter speed", at a target located behind the fighter at a range of more than 5 km. The result was a direct hit on a target drone.
Short-range LOAL engagements are typically undertaken with targeting data from a pilot's helmet-mounted display (HMD), which allows a target anywhere within the field of view to be designated. Australia's upgraded Hornets are equipped with HMDs but the October test was carried out using offboard sensor data supplied by a second F/A-18 via its Link 16 datalink.
"A 'simple' helmet shot is less impressive these days," one programme official told Jane's . "The RAAF firing shows how you'd want to use the missile for real, using data fusion and 360-degree sensor coverage for targeting. It doesn't matter if the target is in the forward or rear hemisphere; the missile is capable of flying to any point, from which the seeker goes active. ASRAAM's incredible speed gets the missile looking into the right place as quickly as possible. The seeker already has a ±90° off boresight capability and reaches a very high angle of attack in flight so there's only a short gap between launch and when missile can see into the 'blind space' behind the launch aircraft."
The Australian engagement was described as "a simulated 'chase down' situation by an enemy fighter". MBDA said: "If the target was behind and above, the ASRAAM would follow the best trajectory based on the available target data. In that situation it would come off the rail, reach the safety point where the fins unlock, and then go back over the top of the launch aircraft."
ASRAAM's LOAL capabilities will be crucial for its future integration with the Lockheed Martin F-35 Lightning II Joint Strike Fighter (JSF). The ASRAAM is scheduled for fielding as part of the JSF's Block 3 configuration, with two internal missiles and the option to carry two externally on a new stealthy pylon. It will be particularly important for the JSF to use passive targeting for weapons like ASRAAM to avoid emissions from its own radar.
The external ASRAAM configuration is now under contract, with test assets delivered to Lockheed Martin. Fit, form and function integration testing is expected to start in April/May.
It has always been a credo of the JSF designers that an aircraft with an external payload cannot be stealthy. However, with ASRAAM, Jane's was told: "It's all a question of conops [concept-of-operations] and how much RCS [radar cross-section] you are prepared to trade off. If you need absolute stealth then you go buttoned up with two air-to-air missiles, but most missions won't demand that. This airplane is not invisible. If you look for it across enough wavelengths or in the IR spectrum you will find it, and if that happens you need to be able to fight your way out."
[SIZE=-1]© 2009 Jane's Information Group[/SIZE]
