Originally Posted by EMAW

Not only these, but Part 135 passenger carrying ops already REQUIRE an SIC, always. Single engine, multi-engine, Turbine, or piston doesn't matter.
You can receive an ops spec that allows the use of the autopilot in lieu of SIC, but that is the exception, not the rule. It's similar to the question of when do you need to file an alternate. The answer is ALWAYS, except.....