The error being made by the other CFI is still pretty common, especially among those who (a) don't play in online forums and (b) perhaps ironically, who have enough real teaching experience to not have to go to an FIRC.
The FAA's arguably unfortunate and counter-intuitive use of "PIC" in two completely different contexts probably makes the distinction between "acting" and "logging" the single most confused requlatory issue to the uninitiated.
You can see it changing, though. There used to be a lot more online arguments about this question that the FAA resolved a long time ago.
Here, for your friend, the text of the almost 27-year old FAA Legal opinion on the subject (note that is specifically deals with your question) Note that the reg sub paragraph numbering has changed, but the substance of the text hasn't:
===========
OCT. 28, 1980
WINSTON SCOTT JONES
Dear Mr. Jones:
This is in response to your letter in which you request an interpretation of Section 61.51(2)(c) of the Federal Aviation Regulations, regarding logging of pilot-in-command (PIC) flight time.
Specifically, you ask what time may be logged as PIC time when the pilot in the right seat is a certificated flight instructor (CFI) along for the purpose of instruction and is not a required crewmember, and the pilot in the left seat holds either a private or commercial certificate in an aircraft for which he is rated.
Section 61.51 is a flight-time logging regulation, under which PIC time may be logged by one who is not actually the pilot in command (i.e., not "ultimately" responsible for the aircraft) during that time. This is consistent with the purpose of Section 61.51, which as stated in 61.51(a) is to record aeronautical training and experience used to meet the requirements for a certificate or rating, or the recent flight experience requirements of Section 61.
Section 61.51(c)(2)(i) provides that a private or commercial pilot may log as pilot-in-command time only that flight time during which the pilot--
1. Is the sole manipulator of the controls of an aircraft for which he is rated; or
2. Is the sole occupant of the aircraft; or
3. Acts as pilot-in-command of an aircraft on which more than one pilot is required under the type certification of the aircraft, or the regulations under which the flight is conducted.
Under Section 61.51(c)(2)(iii) a certificated flight instructor may log as pilot-in-command time all flight time during which he or she acts as a flight instructor. Sections 61.51(b)(2)(iii) and (iv) provide for logging of flight instruction and instrument flight instruction received.
Accordingly, two or more pilots may each log PIC time for the same flight time. For example, a pilot who is the sole manipulator of the controls of an aircraft for which he or she is rated may log that time as PIC time under 61.51(c)(2)(i) while receiving instruction, and the instructor may log that same time as PIC time under 61.51(c)(2)(iii).
There is no provision in the FAR's for logging of "dual" flight time; however, we assume that you are referring to logging time as instruction received. Section 61.51(b)(2)(iii) and (iv) allow flight instruction and instrument instruction received time to be recorded. There is nothing in the FAR's which prevents a pilot from logging the same time as both instruction received and PIC time, as long as each requirement is met. The pilot may also log the same time as instrument instruction. Note, though, that one hour of flight logged both as one hour of PIC and one hour of instruction received still adds up to only one hour total flight time.
You request interpretations of these regulations for situations in which:
1. The purpose of the flight is instruction in advanced maneuvers.
2. The purpose of the flight is simulated instrument instruction in actual VFR conditions.
3. The purpose of the flight is instrument instruction actual IFR conditions.
4. The pilot in the left seat is not current in the aircraft or in the conditions of flight.
5. The purpose of the flight is transition from tricycle to conventional landing gear.
6. The purpose of the flight is obtaining logbook endorsement authorizing operation of a high performance aircraft, as required by FAR 61.31(e).
7. The purpose of the flight is transition to a different type aircraft of the same category and class for which the left seat pilot is rated and a type rating is not required.
In each situation, the CFI may log PIC time for all flight time during which she or he acts as flight instructor. The pilot receiving instruction may also log PIC time in each of these situations, as the pilot is the sole manipulator of the controls of an aircraft for which she or he is rated. Specifically, neither the currency requirements of situation 4 nor the log book endorsement of situation 6 are ratings within the meaning of Section 61.51. "Rating" as used in that section refers to the rating in categories, classes, and types, as listed in Section 61.5, which are placed on pilot certificates.
We trust that this discussion answers your questions.
Sincerely,
EDWARD P. FABERMAN
Acting Assistant Chief Counsel
Regulations and Enforcement Division
============
