Environmental Protection System for the Shuttle External Tank Aft Cargo Carrier

The Shuttle External Tank (ET) can be extended by adding an Aft Cargo Carrier (ACC) approximately 33′ in length in order to provide added volume for payloads. The ACC doubles the current Shuttle payload volume, provides flexibility in payload manifesting, and can be utilized for hazardous payloads. This paper presents the major environmental design requirements for the ACC, and discusses the preliminary design accomplished to meet the most demanding requirement: the increased thermal and acoustic environments. Candidate environmental protection concepts that combine acoustic and thermal protection materials are described, and the more promising selected for testing.