Two subspace sonobuoys, one open and one closed
Subspace sonobuoys are a type of prototype sonobuoys used by the United Nations Cosmo Navy and first used in 2199 during the Encounter with the Garmillas Dimensional Submarine. They use a similar principle to the subspace sonar, and allow to locate a craft hiding in another dimension.[1]
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Japanese language information[]
亜空間ソノブイ A kūkan sonobui