The APKWS (advanced precision killing weapon system ?) isn't like other add-on guidance systems. Rather than being embedded in the nose of the rocket, the APKWS installs between the warhead and rocket motor. This installation doesn't require specialized training or tools, meaning that crews can easily add this capability in the field. The system employs the Distributed Aperture Semi-Active Laser Seeker (DASALS), BAE's proprietary guidance method which mounts fiber-optic sensors on the rocket's pop-out fins. This is done so that multiple guided rockets can be fired at the same time. See, if you try to rapid-fire multiple guided missiles, there's a good chance the rockets in the back of the pack will be damaged by the soot, the flames, the heat, or the chop of the lead rockets. By placing the guidance system further back, more rockets can be fired more quickly and with less interference. What's more, the APKWS can also aim itself autonomously or be guided into its target with a laser designator.
source : http://www.defenseindustrydaily.com/apkws-ii-hellfire-jr-hydra-rockets-enter-sdd-phase-02193/
