Overview

The orbiter/external tank separation system consists of the oxygen and hydrogen umbilical disconnects located at the lower left and right aft fuselage, one forward structural attach point just aft of the nose landing gear doors and two structural attach points located in the orbiter/external tank umbilical disconnect cavities. An umbilical retraction system retracts the orbiter umbilicals within the orbiter aft fuselage, and umbilical doors close over each of the umbilical cavities after separation.

The 17-inch liquid oxygen and liquid hydrogen disconnects provide the propellant feed interface from the external tank to the orbiter main propulsion system and the three space shuttle main engines. The respective 17-inch disconnects also provide the capability for external tank fill and drain of oxygen and hydrogen through the orbiter main propulsion system and the T-0 umbilicals. The liquid hydrogen interface between the orbiter and the ground storage tank is provided by a T-0 umbilical located on the left side of the aft fuselage. The liquid oxygen interface between the orbiter and the ground storage tank is provided by a T-0 umbilical on the right side of the aft fuselage.