The Reddit thread in question surfaces a pair of logbook and currency questions that recur constantly among commercial pilot candidates: whether "PDPIC" time — Performing the Duties of Pilot in Command, the logging privilege under 14 CFR 61.51(e) that lets a rated pilot log PIC time as sole manipulator of the controls even when a certificated flight instructor occupies the other seat — can satisfy night currency requirements under 61.57(b), and whether PDPIC logging has any application beyond the specific aeronautical experience requirements baked into 61.129 for the commercial certificate. Neither question has a flashy answer, but both cut to a distinction that trips up flight students, CFIs, and even experienced pilots: the difference between logging PIC time and acting as pilot in command. Under 61.51(e), a private or commercial candidate flying with an instructor aboard can log PIC time so long as they are the sole manipulator of the controls and rated in category/class/type, regardless of who is legally the acting PIC for operational and liability purposes. Night currency under 61.57(b), by contrast, only requires that the pilot have made three takeoffs and landings to a full stop within the preceding 90 days as sole manipulator of the controls at night — it does not require that the pilot have been the acting PIC for those landings. That means a commercial student flying with an instructor can, in fact, use PDPIC night landings to satisfy 61.57(b) currency, since the regulatory language keys off "sole manipulator," not acting PIC status.
The second question — whether PDPIC logging has utility outside the commercial certificate's training requirements — matters more broadly than it might first appear. Sole-manipulator PIC logging under 61.51(e) is not a special carve-out unique to commercial training; it is a general logging privilege that applies any time a rated pilot flies with an instructor or other qualified pilot and remains the one actually flying the airplane. That means PDPIC-logged hours count toward total PIC time for purposes well beyond 61.129, including building toward ATP minimums under 61.159, satisfying insurance underwriting requirements, meeting employer minimums for corporate or fractional operator hiring, and maintaining flight review or IPC currency. The confusion in the thread likely stems from the fact that most pilots first encounter the term "PDPIC" specifically in the context of the commercial certificate's cross-country and night flight requirements, where instructors explicitly log dual instruction while students simultaneously log PIC time as sole manipulator — creating the false impression that the concept is bounded to that certification pathway.
For working pilots and flight instructors, this kind of granular logging question is not academic pedantry. Logbook entries are legal documents, and misapplied or misunderstood PIC logging has real consequences: it can produce inflated or improperly documented experience that surfaces during airline background investigations, insurance audits, or even NTSB inquiries after an incident. Regional and major airline hiring departments, along with corporate flight departments vetting candidates for type-rating training, routinely scrutinize logbook consistency, and a pilot who cannot articulate why their PIC time is legitimately loggable — or who conflates "logged PIC" with "acted as PIC" — invites unwanted scrutiny. CFIs bear particular responsibility here, since students frequently absorb these nuances secondhand from instructors who themselves learned informally rather than through a rigorous read of 61.51 and 61.57.
More broadly, threads like this one reflect how much of practical FAR interpretation in general aviation training happens not through official guidance but through crowdsourced discussion on forums like r/flying, where CFIs, DPEs, and students debate edge cases that FAA guidance materials address only obliquely. As flight schools and accelerated ab-initio programs push students through commercial and instrument training faster to feed the ongoing pilot pipeline into regional and corporate flying, precise understanding of logging rules — PIC time, cross-country time, night currency, complex/high-performance endorsements — becomes increasingly important to avoid downstream certification or hiring problems. The persistence of these questions also underscores a longstanding criticism of 61.51(e): its "sole manipulator" logging standard, while administratively convenient, creates ambiguity that can inflate apparent PIC experience relative to actual command authority, a gap that airline and corporate operators increasingly account for by scrutinizing not just total hours but the operational context in which those hours were earned.