As for the radar dish on the bow, this is not done because of a few things.
- Radar horizon. The higher the antenna is, the further it can see, due to the curvature of the earth. This is why you often see surface search radars higher in the mast then the other radar systems.
- Field of vision. Due to the high speed of aircraft, forward is where you will be very soon, so most likely where your target is. Especially on early radars, an larger field of vision required a larger weight of the system, so they made the radars longer ranged but focussed on a small field, looking forward instead of around. On a ship, the interesting area might be anywhere and you have a lot more weight and power to distribute, so the antenna's were mounted to look around an not just forwards.
- Spray. Water is not only harmfull for electronics, it also blocks radio waves, so the spray of the waves and your ship moving trough them would hinder your radars effectiveness and also possibly damage it.
- Systems. A ships bow is fairly empty a part of the ship, filled mostly by things like ballast tanks, paint lockers and a bit further aft often things like crew spaces. This is quite something different then electronics, waveguides, cooling systems etc a radar requires. For high effectiveness, you also want your radar displays in your command center, which is done easiest by having all the electronics and systems for them near your command spaces.
So, in essence, and especially on early radars, this requires you to have your radar antenna high up, amidships and with a clear field of vision all around. More setups became possible since then, for example radars on gun mountings, but the general rules are still basically the same.
Drawings are credited with J.Scholtens
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