In mid-2017 the U.S. Marine Corps ordered some of its F-18C to be modified to fire the APKWS II (Advanced Precision Kill Weapons System) laser guided missiles. The marines are already using the APKWS on their AV-8B vertical takeoff jets. The new F-35Ba the marines recently received (o replace the AV-8B) are apparently going to be adapted to handle APKWS as well.
The reason for adapting more fighter jets to handle the APKWS is the realization that smaller is better if you want to avoid friendly, especially civilian, casualties while also being able to carry more of these smaller missiles than any other laser guided air-to-ground weapon. The APKWS became particularly popular in Iraq and Syria over the last few years and in late 2016 the U.S. Department of Defense ordered 3,200 more APKWS II missiles and quickly exercised an option to buy 12,000 more. This contract made it possible for the manufacturer (BAE) to build a new factory in the United States that can quickly expand production to more than 1,600 APKWS II a month. These production orders are mainly for American aircraft and helicopters but also for a growing number of export customers the United States supplies. This includes Iraq, Jordan and Lebanon. By early 2017 orders for APKWS were coming in at the rate 5,000 missiles a year and that has continued to increase as more aircraft are modified to use them.
For a long time there was much reluctance to adopting the APKWS for American aircraft but in 2016 the last holdout, the U.S. Air Force realized that these missiles are extremely effective when used by A-10s and F-16s operating against ISIL (Islamic State in Iraq and the Levant) in Syria and Iraq. In mid-2016 the air force arranged for an emergency shipment of APKWS from the navy (already a regular user) along with making arrangements to get regular shipments direct from the manufacturer. The APKWS II has been available since 2012 but in the last few years demand rapidly increased because of user reports that the 70mm missiles is not only smaller and cheaper than the larger and older Hellfire but worked just as well in combat and sometimes was more effective because of its smaller warhead.
Originally used only on helicopters and UAVs, in late 2013 the U.S. Department of Defense certified APKWS II 70mm laser guided rockets for use on fixed wing warplanes like the A-10, AV-8, and F-16. But only the marines were interested in doing that right away with their AV-8. The APKWS II had to prove it could be successfully launched from fast moving aircraft and still be able to continue in flight to the ground target its laser sensor was attracted to (because of laser light being bounced off it). This was not a tech breakthrough because Britain had earlier demonstrated how effective such small missiles can be when used by “fast movers” (jets). Normally, smaller missiles like this are designed for helicopters, but Britain took the American Hellfire and came up with a version (Brimstone) that worked on jets. It was a big success in Libya in 2011, and earlier in Afghanistan. Users of fast movers took notice.
Since 2010 the U.S. Marine Corps has been using APKWS II for its helicopter gunships and SOCOM has used it on its slow moving AC-130 gunships. The marines were so pleased with it that they bought APKWS II kits to convert some of their 100,000 70mm unguided rockets to laser guided ones. All this began when the marines bought fifty APKWS II missiles for testing and that proved successful. There followed the first sale for 70mm guided rockets after more than a decade of trying to get anyone to buy more than a few evaluation missiles or upgrade kits. The marine AH-1Ws soon had fired over a hundred APKWS II in Afghanistan and it was noted that none of them missed. That led to modifications for use on fast movers and the subsequent successful tests and gradual adaptation by users.
After more than a decade of development effort, by several different companies, there are now several guided versions of the 70mm air-to-ground rocket. Developing a guided 70mm rocket took so long because the manufacturers underestimated the technical difficulties of getting the laser seeker and flight control mechanisms into that small a package, at a weight and price the customer could afford. The price of the new 70mm missile was about $30,000 each and that was about what a JDAM smart bomb cost and less than a third of what a was paid for each Hellfire missile.
The guided 70mm rocket is used against targets that don't require a larger (49 kg/108 pound) and more expensive Hellfire missile but still needs some targeting precision. In tests the APKWS hit within a meter (a few feet) of the aiming point, about what other 70mm laser guided missiles are capable of. The 70mm missile makes an excellent weapon for small aircraft, especially UAVs, since you can carry more of them. The launcher for carrying these missiles is designed to replace the one for Hellfire but can carry four 70mm missiles instead of one Hellfire.
All these 70mm guided missiles are basically 13.6 kg (30 pound) 70mm rockets, with a laser seeker, flight controls, a 2.7 kg (six pound) warhead, and a range of about six kilometers. Laser designators on a helicopter, aircraft, or with troops on the ground, are pointed at the target and the laser seeker in the front of the 70mm missile homes in on the reflected laser light.
The APKWS II weighs 15 kg (32 pounds) with the 4.6 kg (ten pound) M151 high-explosive warhead. There is an optional M282 warhead weighing 5.9 kg (13 pounds) that can penetrate light armor or fortifications (as well as thick brick walls common in Afghanistan and the Middle East). To use the M282 effectively the fire control system has to be modified to allow the pilot to select the delay (if any) on the fuze detonating. Longer delay enables the warhead to go deeper before exploding. The M151 high-explosive warhead kills or wounds within ten meters of the explosion and is favored because it is light, cheap and effective against troops in the open and those inside caves or structures with large windows or thin walls. The APKWS is typically fired from a modified (for laser guided weapons) seven rocket pod used on helicopters since the 1960s. Thus a jet can carry seven APKWS on a hard point versus one (or two) Hellfires. APKWS has a range of 5,000 meters when fired from helicopters (that are low and moving slow, if at all) and up to 11,000 meters from a jet (that normally fires when higher and moving faster).
APKWS is based on the 2.75 inch (70mm) rockets which were developed during World War II as an air-to-air weapon for use against heavy bomber formations. The Germans had developed a similar and very successful weapon (the R4M). Before long it was noted that neither the Japanese nor the Germans had any heavy bombers, so the U.S. 70mm rocket was switched to air-to-ground use. Actually, the 70mm rocket was retained for air-to-air use into the 1950s, but it was never successful in that role. The 70mm rocket became very popular in the 1960s, when it was discovered that the weapon worked very well when launched from multiple (7 or 19 tube) launchers mounted on helicopters. The 108-138m cm (42-55 inch) long rockets could be fired singly or in salvoes and gave helicopter pilots some airborne artillery for supporting troops on the ground. There are many variations in terms of warheads and rocket motors. Some versions can go over ten kilometers.
The marines, and now the navy and air force, believe that a mini-Hellfire, in the form of their APKWS II, has a role on the battlefield and plan to keep using it in combat. The APKWS is not only a lot cheaper than Hellfire but for a growing number of situations is seen as a better choice.