Even with incorporation of Western technology, the chronic lack of adequate shipborne air defense systems has had great impact on PLAN operations. Equipped with a small number of surface-to-air missiles with visual-range only and guns with limited range and performance, Chinese warships have historically limited their operations to the area covered by their land-based aircraft due to a lack of fleet defense capability. To rectify this trend, the Luhu destroyers (and the smaller Jiangwei class frigate) were fitted with the HQ-7 SAM that gives them much better air defense capability than other previous Chinese designs, although they are still limited to within visual range (WVR).