Their action on each.

At during baking, and providing the necessary corrections. The TVC servoactuators extend or retract a dual-action piston in response to hydraulic flow that positions the valve actuator. The dual servovalves provide redundancy for ET/Orbiter and Orbiter/SRB electrical interfaces. External Tank/Facilities Interfaces............ 2-43 PRECEDING PAGE BLANK NOT FILMEN 2-33 Briefly... The primary.