LWIR staring at 384x288 focal plane array (FPA) have been developed and investigated. FPAs are manufactured on the base of mercury cadmium telluride epitaxial layers grown both by liquid phase epitaxy (LPE) and molecular beam epitaxy (MBE). 384x288 FPA consists of a MCT photodiodes array formed in the p-type layer by ion implantation and silicon MOS-multiplexer. The photodiodes array pitch in each direction is 35 micrometers . Multiplexer performs the photocurrents integration during line period, signals multiplexing and output form the focal plane. MCT photovoltaic array and MOS-multiplexer are bonded together by indium bumps. Sensitive unit is packaged in a metal dewar and cooled down to temperature 80 K. Average detectivity was more than 1.5x1010W-1cm/s-1/2 for FPA with cutoff wavelength of 11.9 micrometers at T=80K. Test IR system on the base of FPA was developed to obtain IR-images in real time mode with frame frequency 25 Hz. Test IR system performs two-point image correction and defective elements replacement.