Closeup view of docking system of the Apollo spacecraft

S68-50870 (1968) --- An engineering set up illustrating the probe portion of the docking system of the Apollo spacecraft. During docking maneuvers the docking probe on the Command Module (CM) engages the cone shaped drogue of the Lunar Module (LM). The primary docking structure is the tunnel through which the astronauts transfer from one module to the other. This tunnel is partly in the nose of the CM and partly in the top of the LM. Following CSM/LM docking the drogue and probe are removed to open the passageway between the modules.