The open panel at left was hiding various programmable equipments related to the radio-navigation system. The mention Pion-NM on the panel above was the antenna-feeder system of the short-range navigation system Korall-I. The closed panel below, between the two open, had the mention Kontrol 141M/Vikkod SVS. Izdelie 141M was the ECM complex and SVS was the abbreviation of "alcohol-water mixture" necessary to cool the electronics (it was a draining point). One of the two emitting antennas of the SPS-141M/142 ECM suite can be seen right above the nose landing gear. A second similar fairing was on the other side of the nose and a third antenna was located under the nose, flush with the fuselage.