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> Ground radar is line-of-sight. The Earth is round. Anything below the horizon is invisible. That's not true. Ground based radar can see over the horizon (hen
by jjk166 5mo ago
> Ground radar is line-of-sight. The Earth is round. Anything below the horizon is invisible.
That's not true. Ground based radar can see over the horizon (hence the term Over-the-horizon radar) by taking advantage of the refractive index of air, allowing the radar waves to essentially curve along, as well as by bouncing radar waves off the ionosphere.
Given that this is the foundation of TFA's argument, it does not instill confidence.
https://en.wikipedia.org/wiki/Over-the-horizon_radar https://en.wikipedia.org/wiki/Over-the-horizon_radar
- echoangle 5mo agoOn the other hand, those only really tell you that something is coming somewhere in that direction, OTH radars don't have the resolution for targeting afaik.
- jjk166 5mo agoKnowing that it's coming and the general direction is what you need for command and control, the actual interceptor is going to be much more limited in range than the targeting radar.
- protortyp 5mo agoExactly. In an earlier draft I went deeper into this, but cut that section among others for brevity.
- adrian_b 5mo agoOver-the-horizon radars have very poor resolution, so they are useful only for early warning, not for guiding an interceptor. For targeting at distance, you need antennas mounted on high masts or airborne radars.
- jjk166 5mo agoYou don't need to target at distance, you are limited by the range of your interceptor. OTH tells you which interceptor battery needs to be looking where.
- protortyp 5mo agoI cut this on purpose due to the poor resolution other commenters have mentioned already.
- jjk166 5mo agoYou shouldn't have because the poor resolution is irrelevant and OTH radar is widely used in BMD systems.