CLAM SHELL-Low Level EW & ACQ RadarFrequency (Freq) [MHz]2900 3300 (5 channels)

Pulse Width (PW) [us]FMCW

Pulse Repetition Frequency (PRF) [Hz]-

Pulse Repetition Interval (PRI) [us]-

Peak Power [kw]700

Average Power [kw]0.7

Displayed Range [km]About 450

Range Resolution [m]180

Mainlobe Width [degree]2

Sweep Rate [RPM]6

Deploy/Stow Time [min]About 60

Pic 1 5N66M Clam Shell Low Altitude FMCW(frequency modulated continuous wave) Search and Acquisition Radar for the static SA-10A/Mobile SA-10 B (S-300 PMU) Grumble SAM system.DescriptionsThe 5N66/5N66M/76N6 Clam Shell low level early warning and acquisition radar. It is an unconventional frequency modulated continuous wave design, using a split antenna arrangement with a large beak to prevent spillover from the transmitter. In configuration it is thus closest to the 5N62 Square Pair engagement radar used with the S-200/SA-5 Gammon SAM. Quoted performance figures include the detection of targets with an RCS as low as 0.02 square metres, at speeds of up to 1,400 kt, with a bearing resolution of 1 degree, velocity resolution of 9.3 kt and range resolution of 2.15 NM. Quoted RMS tracking errors are 0.3 degree in bearing, 4.7 kt in velocity and 1 NM in range. Chaff rejection performance is quoted at better than 100 dB, detection range is stated to be 50 NM for targets at 1,500 ft altitude, and 65 NM for 3,000 ft altitude. The transmitter delivers 1.4 kW of CW power at an unspecified carrier frequency, system MTBF is quoted at 100 hr with an MTTR of 0.5 hr.

This family of radars is best known as the acquisition component for the S-300P/PM/PMU/PMU1 SA-10/20 Grumble/Gargoyle SAM system. It has been largely supplanted in newer S-300P/S-400 configurations by the LEMZ 96L6E.