Stand-in Attack Weapon (SiAW) is the somewhat bumpy name of a new missile from Northrop Grumman, which was fired for the first time for test purposes just a few days ago. In contrast to “stand-off” weapons, i.e. missiles or glide bombs that are fired from outside the range of air defense systems, the F-35 is designed to fire the SiAW within the range of enemy air defense missiles.
This also reflects the realization that even “stealth” aircraft can no longer move deep into enemy airspace for any length of time. Instead, their stay in the detection range of enemy air defense nets should be as short as possible and ideally at the edge of the “air defense bubble”. The aim of the Stand-In Attack Weapon is to engage rapidly deployable targets in the Anti-Access/Area Denial (A2/AD) category. A2/AD” refers to those air, ground and sea areas that the enemy actively seeks to prevent from being used by deploying comprehensive defensive measures.
The US Air Force (-> current news about the US armed forces) includes launch facilities for ballistic missile launchers, mobile launchers for ground-to-ground or ground-to-ship cruise missiles, jammers to interfere with the electromagnetic spectrum, anti-satellite systems and integrated air defense network systems.
The days when the first generation of stealth attack aircraft could still get over their targets and drop free-falling laser-guided bombs, as was practiced in Iraq in 1991 (Operation Desert Storm) and in Yugoslavia in 1999 (Operation Allied Force), are definitely over. Modern surface-to-air and air-to-air missiles have very long ranges and enough energy to be able to maneuver well on final approach to the target. The active sensors in the missiles no longer necessarily require information from the radar on the ground after launch; they find and identify their targets themselves at the end of the flight path and increasingly often hit their targets directly.
Russian and Ukrainian pilots have also had to come to this realization over the past three years (-> current news from the war in Ukraine) painfully. Only a small minority still manage to escape from a hit aircraft using the ejection seat. Modern missiles can often no longer be deflected and no longer rely on proximity fuses to release a cloud of fragments near the target. The majority of pilots die from a direct hit. As a result, pilots are keeping more distance from their targets and enemy air defense systems, while the focus is increasingly on weapons that can cover greater distances more quickly.
The Stand-In Attack Weapon (SiAW), developed and built by Northrop Grumman, is designed to take out time-critical and mobile key targets in the initial phase of a conflict – without putting its own forces at undue risk. The US Air Force has so far withheld specific technical details, leaving analysts to rely on observations and educated guesses.
It is obvious that the SiAW was derived from the brand new AGM-88G Advanced Anti-Radiation Guided Missile-Extended Range (AARGM-ER) anti-radar missile. This missile is 4.06 meters long, has a diameter of 29.21 centimeters and weighs 467 kilograms. Both weapons use the same flight control and sensor system. This includes a GPS-supported inertial navigation system and a millimeter-wave radar that is capable of independently locating, classifying and identifying targets. A two-way data link also makes it possible to transmit data in the final moments of the flight to ensure that the target has actually been hit.
Specific details on the range or speed of the SiAW and the AGM-88G are not yet known. However, it would be surprising if it were not faster and flew further than the previous generation, as is generally the case. The speculation that the weapon will reach the hypersonic range (Mach 5+, over 1,715 m/s ) is also permissible because with Lockheed Martin an inferior competitor in the SiAW program, continues to promote its project and seek customers – and openly advertises the weapon called Mako as a hypersonic missile.
Northrop Grumman’s SiAW program and costs
Development of the SiAW (Stand-In Attack Weapon) began in 2018 when it was first included in the US Air Force’s research, development, test and evaluation budget. In May 2022, contracts were awarded to L3Harris Technologies, Lockheed Martin and Northrop Grumman to develop concepts for the SiAW. In September 2023, Northrop Grumman was awarded a development contract worth 667 million euros. This includes the production of prototypes, the provision of test facilities and a total of four flight tests. Northrop Grumman delivered the first airworthy SiAW to the US Air Force in November 2023. Flight testing is currently in full swing.
The US Air Force has set itself the goal of achieving initial operational capability of the SiAW for the F-35A by 2026 at the latest. In total, the procurement of 3,000 SiAW missiles is planned, at an estimated total cost of just under 8.5 billion euros. The weapon is primarily intended for the F-35A and the B-21 Raider (-> Super bomber B-21 Raider flies for the first time). However, it is expected that non-stealth carrier systems such as the F-16 and F-15 will also be able to use the SiAW. However, their use by fourth-generation fighter aircraft would probably be limited to scenarios with less technically advanced air defense systems.
Here for more news about the US armed forces.
