The telescope housing viewed from inside the airplane. Large servo motors are located around the experiment mounting plate to control pointing of the telescope. TV cameras, attached to the telescope, allowed the computer system to automatically track targets. The TV cameras were not used for data collection. This was before the days of CCD cameras. Sensitive infrared detectors were connected to the telescope for the actual measurements. You can see one in the center of the picture. They were usually solid state sensors cooled with liquid nitrogen and/or helium.