History of VLF/ELF submarine radio communications from WWI-era accidents through NAA Cutler’s 1.8 MW transmitter still operating today.
Key Takeaways
Seawater blocks HF radio within meters; VLF (below 30 kHz) penetrates far deeper, discovered accidentally in 1917 when engineer John Willoughby dropped a coil antenna into Chesapeake Bay.
Willoughby and Percival Lowell proved the concept on submarine D-1 at New London in 1918; the Navy standardized long-wave submarine comms within years.
NAA Cutler, Maine (callsign inherited from 1913 Arlington station) went live 1961: two antennas each spanning 6,000+ ft, supported by 13 towers up to 1,000 ft tall, driven by a 2 MW Continental Electronics AN/FRT-31 transmitter.
Ice loading forces Cutler to switch each antenna into a 3 MW heating element periodically to melt accumulation before tower tension limits are exceeded.
VLF sites at Cutler, Jim Creek, LaMoure, Lualualei, and Aguada (tallest structure in the Caribbean at 1,205 ft) form the backbone of submarine C2 and remain operational.
