We propose a high-performance broadband infrared focal plane array (FPA) for the Thermal Infrared Sensor (TIRS) on NASA's LANDSAT satellite. The FPA will feature a cutoff wavelength of 13 microns, operate at > 55K, have a format of 640x512, quantum efficiency > 30%, and will be realized using Type-II InAs/GaSb strained layer superlattice (SLS) photodiodes. In Phase I we will develop the basic diode with extended cutoff wavelength and pixel passivation improved in order to support high temperature operation. Phase II will optimize design, material, and process to develop and deliver FPAs to NASA-GSFC for evaluation. The relatively high operating temperature promised by SLS is expected to be of particular benefit to LANDSAT.