“SIT DOWN, shut up, and hold on” might work as a passenger briefing in an action movie, but in the real world, it falls short of adequate. Or even legal, for that matter.
The FAR in question is 91.107: Use of safety belts, shoulder harnesses, and child restraint systems. Its only real requirement is that, before takeoff, “each person on board is briefed on how to fasten and unfasten that person’s safety belt and, if installed, shoulder harness.” That’s it for Part 91 operators. (If you’re flying 135 and/or 121, see FARs 135.177 and 121.571.)
The good news is that, for the most part, there’s no limit to how far beyond that bare minimum we can go. But we also could come up with a plan, or maybe even a…