The Delta III class are fitted with a new sonar system, the MGK-400 Rubikon (in submarine "K-424", the older MGK-100 Kerch was installed), developed under the leadership of main designer S.M. Shelechov. The Rubikon can operate in infrasound frequencies, and contains automated systems for target classification. Its maximum range in ideal hydrologic conditions is about . The Delta III class are equipped with a new battle management system, the "Almaz-BDR" (or "MVU-JZBDR") torpedo fire control. For improved stealthiness, a new inertial navigation system, Tobol-M-1 (on newer ships Tobol-M-2), with higher accuracy, was installed. Tobol-M works with data from two observatories which are saved for two days, and also contains a hydro-acoustic navigational station ("Shmeľ" or "Bumblebee"), which allows the submarine to determine its position from hydro-acoustic buoys. The Delta III class includes the "Molnija-M" communications system, with satellite capabilities provided by the "Tsunami" subsystem.