predicted line of sight

{{Short description|Missile guidance method}}

Predicted line of sight (PLOS) is a method of missile guidance.{{Cite patent|number=US6672533B1|title=Method and guidance system for guiding a missile|gdate=2004-01-06|invent1=Regebro|inventor1-first=Christer|url=https://patents.google.com/patent/US6672533B1/en}} In PLOS, the operator tracks the target with the missile launcher's onboard sights for a short period of time (typically 3–5 seconds). Software on the missile extrapolates from the gathered data to generate a predicted flight path required to intercept the moving target.{{Cite web|url=https://armyrecognition.com/military-products/army/anti-tank-systems-and-vehicles/rocket-launcher/nlaw-next-generation-light-anti-tank-missile-weapon-data-fact-sheet|title=NLAW|website=armyrecognition.com}} When fired the missile uses inertial navigation to fly this course and hopefully engage the target either by direct contact or via proximity fuse detonating the warhead.{{Cite web|url=https://www.army-technology.com/projects/mbt_law/|title = MBT LAW Light Anti-Tank Weapon}} This method is employed by anti-tank weapons such as the NLAW and FGM-172 SRAW.

For a moving vehicle, the course will be a curve, the greater the angular velocity of the target from the launcher the smaller the radius of the curve. The curve is such that if the launcher had kept tracking the target after launch the missile would always be on the line between the launcher and target. This is what is attempted by command to line of sight (CLOS) but in the case of PLOS, no commands are issued post-launch and the target is not tracked by either the missile or the launcher. It is a fire-and-forget technique.