Back when the F-22 was in production, I was in the building in Seattle where the carbon fiber wing skins were being laid up using an automated tape placement ma

Back when the F-22 was in production, I was in the building in Seattle where the carbon fiber wing skins were being laid up using an automated tape placement machine. The machine head would come down to a precise 3D location on a complex contoured mold, contact it with a precise pressure, lay out a tow of CFRP tape prepreg for a precise length, then trim it to a specific geometry. Before the machine started the next tow, it extruded an inch of tape, trimmed it for the start of the next tow. At this point, a mechanic would reach over with a spatula taped to a length of steel electrical conduit to collect the little piece of scrap and throw it away. I asked a manufacturing engineer why they did not just add a little vacuum hose to collect the trim - Apparently the mechanic's union contract required each machine to have a full-time operator, and they had to invent a task for the operator to do to keep them engaged.