Retractable lens have major tactical advantages over fixed, it means in long range engagements the enemy will have to either guess what distance to engage at, or fire missiles at max range and lose lock after lens retract.F-35 has three but they are not retractable.
Probably figured that they don’t contribute that much to RCS (hopefully based on testing). Also the dispenser location of Chinese (and Russian) jets seem to differ from the US in general. For example the F-18, F-22 and F-35 all have them positioned in the mid-section and on the bottom, while many Chinese and Russian jets (notably flankers, J-20 and J-35/35A) seem to place the dispensers on the tail boom (or tail booms) in the rear of the aircraft. Maybe positioning has some influence on whether to have covers?So the the flare and chaff dispenser appears to not have a hatch covering them, but is exposed unlike the F-35. Does anyone know why?
Probably figured that they don’t contribute that much to RCS (hopefully based on testing). Also the dispenser location of Chinese (and Russian) jets seem to differ from the US in general. For example the F-18, F-22 and F-35 all have them positioned in the mid-section and on the bottom, while many Chinese and Russian jets (notably flankers, J-20 and J-35/35A) seem to place the dispensers on the tail boom (or tail booms) in the rear of the aircraft. Maybe positioning has some influence on whether to have covers?