Submarine in Fort Lauderdale?

[Akimbo]

Is sonar limited to submarines? Why couldn't it have been a surface ship?

Definitely not. Ships and planes (sonobuoys) looking for subs use active sonar a great deal. Passive sonar on subs is generally more effective because they are so quite, usually running slow, and don't have to deal with surface noise as much.

 

[seeker242]

Is sonar limited to submarines? Why couldn't it have been a surface ship?

No, even fishermen use sonar.

 

[Akimbo]

No, even fishermen use sonar.

Technically acoustic fathometers and fish-finders are active Sonar, which stands for SOund Navigation And Ranging. Of course military ships also use Sonar for ASW (Anti-Submarine Warfare), primarily in active mode. Hull, machinery, and propeller noise is so high on a surface ship that there's no hiding from subs.

There's an old saying: There are only two kinds of ships in the Navy, submarines and targets.

 

[seeker242]

Technically acoustic fathometers and fish-finders are active Sonar.

Technically yes. Although the fisherman use fathometers, fish finders and full on sonar. Or at least what I consider to be "sonar". But the cheapest "sonar" generally starts at 13k and can go up to 75k, depending on how rich the guy is. Some sport fishing guys have a lot of money to spend on their boat. Especially the guys that like to compete in international tournaments where the prize for first place can be more than 1 million $$!

 

[Akimbo]

Especially the guys that like to compete in international tournaments where the prize for first place can be more than 1 million $$!

Heck, I'd invest in a towed side-scan sonar for that much cash. Better yet, install one on your boat and sell your services to the highest bidder.