This subject area describes the procedures for conducting ordinary, pre-engineered, and critical lifts. It discusses the requirements for:
Whenever the center of lift is below the loads center of gravity, stability concerns need to be addressed. Guidance on stability issues and analysis techniques can be found on the presentation: " Geometric Instability Considerations And Criteria for Below the Load Lifts Using Strong-bacs and Spreader bars" (pptx). A short video: "Topex_Swing" demonstrates an incident when a NASA space payload which was rigged using a “H” type below the hook fixture to lift was attached to the bottom of the load was allowed to rotate. NASA Lesson Learned TOPEX Unstable Lift (pdf) summaries the findings from the incident.