SLS tubing contaminated

NASA discovered a contamination problem with tubing in part of the core stage of the first Space Launch System vehicle. According to SpaceNews, Aerospace Safety Advisory Panel member Don McErlean said at a May 17 meeting that a routine inspection of the core stage being built at Michoud Assembly Facility in New Orleans found contamination in the engine section that holds the SLS’s four RS-25 engines and associated systems. The contamination is paraffin wax, used to keep the tubes from crimping while being manufactured. The prime contractor, Boeing, determined the unnamed vendor was not fully cleaning the tubes as required. The contamination was initially found in a single tube, but later checks found similar residue in other tubes. All the tubing in the core stage is now being inspected and cleaned. It’s unclear if it will cause a delay. NASA previously said it expects the core stage to be completed and shipped to Stennis Space Center, Miss., at the end of this year for a green run engine tests by mid-2019, after which it would go to the Kennedy Space Center to be prepared for launch on Exploration Mission (EM) 1. (Source: SpaceNews, 05/17/18)