A modern jet engine inlet protection system that protects against large birds and operates autonomously, that is dormant in routine aircraft operations, that automatically actuates its protective device(s) only at the immediate point of need, then returning it (them) to a non-interfering position, including a RADAR system and a LIDAR system which detect birds entering the intended flight path of the aircraft, and fast computer-implemented computational algorithms that track and identify those from the detected set that are (1) projected to enter a zone which would lead to ingestion by the engine, and (2) of a size large enough that they would seriously damage the engine if ingested; that includes defensive mechanisms housed in the engine nacelle cowling or center hub, or in the fuselage structure that are instantaneously actuated shortly before arriving at the point of impact to shield, deflect, reduce the size of the approaching bird to an acceptable mass, or destroy it, and, that after the ingestion threat has passed, the devices are stowed/retracted or safely jettisoned.