I can't find where the target distance is shown on the F-15C HUD

[mettrak]

I’ve been struggling for hours, and I really need help finding the range indicator on the HUD

[美好岁月里的温柔之人]

I might be wrong with these information because I’m not familiar with the style of heads-up display used in the F-15 and other american-made airplanes, but going straight to the answer:

This is the range indicator, in the F-15, it’s measured in nautical miles, the 620 value should be translated into ~11 km from the target.

This image should be useful to look later.

- YouTube

And this video should be straight-forward regarding F-15C’s heads-up display. Since you’re using gun mode and I don’t think it’s possible to change between gun mode and MRM mode, the informations may slighly vary.