Space Shuttle Program Manifest Process & Flight Opportunities for Small Payloads
The Space Shuttle Program has, since the early flights, exerted great effort to maximize the cargo complement for each individual mission. Historically, because of the capabilities of the Space Shuttle, there have almost always been opportunities to fly what are termed secondary payloads on every mission. However, with the challenges associated with assembling the International Space Station, accommodations for secondary payloads are significantly limited. In an attempt to deal with this situation, the Space Shuttle Program has developed techniques that will identify and utilize flight opportunities, as well as policies that may create opportunities.
Swalin, Richard M.↗