US Navy submarines can receive messages while submerged, but can't respond without raising antennas and exposing themselves. That's why Lockheed Martin is developing a system of buoys that will be able to relay surface signals to submerged submarines:
The idea was to excite the upper atmosphere with high-frequency radio waves, and it would then emit the ELF bands required for one-way communicate with submerged submarines.
The new system is the first two-way communication method for submarines at depth. The actual depth is classified, but according to Reints the cables attached to the tethered buoys are “measured in miles” and would allow them to be launched from “a significant depth.” The submarine could continue normal operations at its normal speed while communicating.
Link via DVICE | Image: Lockheed Martin
weren't operating anywhere close to P3's. Seems to me all those buoys present a much larger target than sticking a comm antenna barely above the surface.
My last duty station was at Navy Radio Transmitter Facility (NRTF) Annapolis (NSS-9) MD. We put out LF and VLF submarine broadcasts. Since radio freqs are inversely proportional to the size of their transmitters ours were so large you could walk around inside of them. Not while transmitting of course. GGGG You could hold a fluorescent light bulb above your head outside at night and it would glow like a light saber from the residual RF from our humongous top hat antenna. (Antenna was so tall you could see DC 25 miles away from the top.) Was really neat to see them glowing like crazy! Just don't touch the two metal contacts on the bulb or you might start
glowing also. Or at the very least be picking your sorry butt off the ground. GGGG NAA Cutler ME was another East coast
sub bcst site. If both of us were off the air for longer than a minute the subs would start getting ready to launch their missiles. NSS-9 was shut down donno if NAA is still operating.
Kalel - They have a lot more to keep them busy than mundane things like the Internet.