Hello Evgeni: Yes the CB Radios Will quit well over water, with a good antenna.
Back in the Late 1960’s and early 1970’s I worked on my Dads (CB Handle Commodore) Commercial Fishing Boat, a converted WWII Army (104 Ft) Crash Boat that was made for long range patrols. It was converted to a Albacore Tuna Fishing Boat. It had three 671 GM Diesel Engines and two 371 50 KW DC Generators, and an old complement of WWII Electronics such as APN-9 Loran, ADF (Automatic Direction Finder), and a old 1938 type Manual operated antenna type Radio Direction Finder.
As newer electronics was installed, replacing the WWII electronics, we used the manual radio direction finder unit, and modified it with a two element CB Quad antenna. This old radio was housed in a big metal box mounted to the boats wheel house ceiling, with a wheel on the bottom to turn the antenna with a 360 degree compass indicator. Now with a CB Quad Antenna mounted on it, we could Direction Find CB Signals using a General Radiotelephone Super MC11A Radio.
This paided off many times as the two element quad antenna and radio could detect CB signals 30 miles on a good night, and we could direction find them, and with experience we could give a good guess as to their distance. This allows us to travel at night to get to a better fishing location.
Some Boats in the fishing fleet though the CB Radio was a “Mickey Mouse” Radio, not travelling too far. In Fact they called the CB Radio the Mickey Mouse Radio. But we DF’ed them many times, as they would talk about their amount of Albacore Tuna Fish caught, thinking the Mickey Mouse radio didn’t travel too far, and they didn’t talk about their Albacore Tuna catch numbers on the Marine AM HF Band (2 to 8 MHz) Radios that would reach all over the world.
But they did use “Pirate Frequencies” illegal frequencies on the Marine HF Band, and out of the Marine HF Bands. Special Channel Crystals would be installed in the radios and time coordinated schedules between boats contact would be made, you could hear the Diesel Engine in the background, and they used handles and such. This practice of pirate frequencies isn’t used as much with the new Marine HF Radios having a small portion of the HF Band, on several bands to allow a much better use of the HF Band for Marine use.
Many Pilots flying commercial flights all over the world, would complain that Eagle 1 was talking to Betty Ann on their HF Frequencies with a Diesel Engine in the background audio, giving catch counts and locations in Lat and Long Numbers, or Compass Rose on the Marine Maps locations.
So yes these bare foot CB Radios did work quit well, using a dipole vertical, made from wire and a Bamboo pole holding them up. During this time we didn’t have the VHF radios yet, but being on a sail boat with different antennas at different heights we were able to talk 40 to 50 miles with a good received signal.
Jay in the Mojave