§ 2.1 named the mechanism: under § 107.12(a)(2) an uncertificated person may fly the aircraft while under the direct supervision of a remote pilot in command who has the ability to immediately take direct control. What that phrase demands in practice is where crews actually get this wrong, and it is worth being blunt about. Direct supervision is not standing nearby offering encouragement or calling out advice — it is being positioned and equipped to seize control of the aircraft at once. Part 107 prescribes no method, and AC 107-2A offers three that would satisfy it: a “buddy box” system linking two control stations, standing close enough to physically take the control station, or an automation system the remote PIC can engage at once to put the aircraft into a safe mode such as a hover or return-to-home. Those are examples, not a closed list — what the rule fixes is the capability, not the mechanism. One point of scope is easy to miss: this route is not only for people who hold no certificate. AC 107-2A applies it equally to a certificated remote pilot who has fallen out of the § 107.65 recurrency window — without current recency you may not fly unsupervised either, and direct supervision is the same door back. If the remote PIC could not take control immediately, the supervision does not satisfy § 107.12 and the person on the controls is not lawfully flying at all — the arrangement fails, not merely the moment it is tested.

The other half of the section is what no crew arrangement can reach. § 107.12(b) says no person may act as a remote pilot in command without holding the certificate, so delegation runs one way only: a certificated remote PIC may lend the CONTROLS to an uncertificated helper, but no one may borrow the AUTHORITY. That asymmetry sits underneath every arrangement in this chapter. The hands on the aircraft can change hands freely; the name answering for the flight cannot change at all.