Det är en "Standby-reticle":
A fixed standby reticle (Figure 7–151) is available in the upper right side of the HUD for use in performing visual designations in the event of a HUD failure. The reticle is fixed at a 15-mil depression angle from the gun boresight. If the HUD fails, the HUD symbology is available by selecting HUD via the menu on the left or right DDI [Digital Display Indicator]. To perform a HUD designation in the NAV or A/G [Air/Ground] mode when the HUD is inoperative, the pilot first places TDC [Target Designator Control] priority to the HUD (either by placing the sensor switch to the normal HUD position, or to the left or right DDI displaying the HUD symbology). The mission computer slaves the radar in AGR mode to the LOS [line of sight] of the HUD standby reticle. The pilot maneuvers the aircraft to position the standby reticle over the aim point and actuates the TDC to perform the designation. The aim point position at the LOS of the standby reticle is computed. The pilot may use the HUD display on the left or right DDI to null the steering error when automatic weapon delivery is being conducted.
Standby-reticle används när HUD misslyckas för att utse mål. Piloten måste luta sig till höger och ställa upp korshåren med pricken så att siktet är korrekt.