Extravehicular Activity (EVA) Hardware and Operations Overview

Definition of Spacesuits• Spacesuits• Typically, 2 types of pressurized "spacesuits' have been constructed to support our space programs• Launch, entry, and abort (LEA) spacesuit -Used to protect crewmembers from launch, ascent, abort, landing and other dynamic loading.-Capable of providing protection from loss of cabin pressure and crew rescue following landing.• Extravehicular Activity (EVA) spacesuit -Used to allow crewmembers to work effectively in the harsh external space environment (provides protection from vacuum, thermal, mircrometeoroids, radiation, etc.).Launch/Entry Suit EVA Suit 4 Historical Overview • First EVA was conducted by USSR/Alexi Leonov on March 18, 1965.-Many EVAs have since been accomplished by the Soviet Union & Russia continuing into the International Space Station era.U.S. EVA Experience • Gemini EVA Experience --Astronaut Edward White II performed first U.S. EVA during Gemini IV June 3, 1965.-Start of EVA program was excursion to perform a special set of procedures in a new and hostile environment.-Proved EVA to be a viable technique for operations outside the spacecraft crew compartment.-Problems encountered: helmet fogging, overheating due to high metabolic activity (primarily due to suit constraints and lack of training).-Gemini Extravehicular Spacesuit and Life Support• 5-layer Gemini spacesuit was intended primarily for Intravehicular Activity (IVA).• 2 additional layers were added for EVA (making 7 layers total).• An umbilical was used to tether the EVA crewmember to the spacecraft and to supply breathing oxygen.-5 Gemini missions involved nine EVAs for a total of 12 hours and 22 minutes of EVA.