Here's a letter of interpretation I found via Google. I can't absolutely vouch for its authenticity, since I didn't get it off my Summit CD, but it matches the interps I have. I've bolded the pertinent sections.
Mr. Michael G. Tarsa
Dear Mr. Tarsa:
Thank you for your letter of April 3, 1991, in which you ask questions about logging pilot in command (PIC) and second in command (SIC) time when operating under Part 135 of the Federal Aviation Regulations (FAR). We apologize that staff shortages, regulatory matters, and interpretation requests received prior to yours prevented us from answering your questions sooner.
Your letter presents the following scenario: a Part 135 certificate holder conducts operations in multiengine airplanes under instrument flight rules (IFR). The operator has approval to conduct operations without an SIC using an approved autopilot under the provisions of FAR 135.105. The operator has assigned a fully qualified pilot, who has had a Part 135 competency check, to act as SIC in an aircraft that does not require two pilots under its type certification. Although FAR 135.101 requires an SIC for Part 135 operations in IFR conditions, the autopilot approval is an exception to that requirement.
You correctly state that while the SIC is flying the airplane, he can log PIC time in accordance with FAR 61.51(c)(2)(i) because he is appropriately rated and current, and is the sole manipulator of the controls. Additionally, he has passed the competency checks required for Part 135 operations, at least as SIC.
You then ask two questions. The first asks whether the pilot designated as PIC by the employer, as required by FAR 135.109, can log PIC time while the SIC is actually flying the airplane. The answer is yes.
FAR 1.1 defines pilot in command:
(1) Pilot in command means the pilot responsible for the operation and safety of an aircraft during flight time.
FAR 91.3 describes the pilot in command:
(a) The pilot in command of an aircraft is directly responsible for, and is the final authority as to, the operation of that aircraft.
There is a difference between serving as PIC and logging PIC time. Part 61 deals with logging flight time, and it is important to note that section 61.51, Pilot logbooks, only regulates the recording of:
(a) The aeronautical training and experience used to meet the requirements for a certificate or rating, or the recent flight experience requirements of this part.
FAR 61.51(c) addresses logging of pilot time:
(2) Pilot in command flight time. (i) A recreational, private, or commercial pilot may log pilot in command time only that flight time during which that pilot is the sole manipulator of the controls of an aircraft for which the pilot is rated, or when the pilot is the sole occupant of the aircraft, or, except for a recreational pilot, when acting 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.
(ii) An airline transport pilot may log as pilot in command time all of the flight time during which he acts as pilot in command.
(iii) (omitted).
(3) Second in command flight time. A pilot may log as second in command time all flight time during which he acts as second 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.
As you can see, there are two ways to log pilot in command flight time that are pertinent to your question. The first is as the pilot responsible for the safety and operation of an aircraft during flight time. If a pilot is designated as PIC for a flight by the certificate holder, as required by FAR 135.109, that person is pilot in command for the entire flight, no matter who is actually manipulating the controls of the aircraft, because that pilot is responsible for the safety and operation of the aircraft.
The second way to log PIC flight time that is pertinent to your question is to be the sole manipulator of the controls of an aircraft for which the pilot is rated, as you mention in your letter. Thus, a multiengine airplane flown under Part 135 by two pilots can have both pilots logging time as pilot in command when the appropriately rated second in command is manipulating the controls.
We stress, however, that here we are discussing logging of flight time for purposes of FAR 61.51, where you are keeping a record to show recent flight experience or to show that you meet the requirements for a higher rating. Your question does not say if the second pilot in your example is fully qualified as a PIC, or only as an SIC. This is important, because even though an SIC can log PIC time, that pilot has not qualified to serve as a PIC under Part 135.
An example of this difference is FAR 135.225(d), which raises IFR landing minimums for pilots in command of turbine powered airplanes flown under Part 135 who have not served at least 100 hours as PIC in that type of airplane. Served and logged are not the same in this context, and no matter how the SIC logs his time, he has not served as a PIC until he has completed the training and check rides necessary for certification as a Part 135 PIC.
Approval for single pilot operations with use of an operative approved autopilot system under FAR 135.105 gives an operator an additional option in the conduct of operations. It does not mandate that all future flights be conducted in that manner. The operator can elect to fly trips with two pilots, as is otherwise required for flight in IFR conditions under FAR 135.101, using the second in command instead of the autopilot.
Your second question asks if, under the circumstances given above, the SIC can log time as SIC when the designated pilot in command is flying the aircraft. The answer is yes, as long as the certificate holder is using the SIC as a crewmember instead of exercising the autopilot authorization. In other words, the certificate holder elects not to conduct an IFR flight using the single pilot with a functioning autopilot option, but rather conducts an IFR flight using two qualified pilots. The two pilots are then "required by the regulations under which the flight is conducted", FAR 61.51(c)(3), and the assumption is that the second pilot (SIC) will function as a required crewmember, and SIC time may validly be logged. However, if for some reason another qualified pilot "rides along" and does not function as a crewmember, then second in command time may not be validly logged.
This interpretation has been prepared by Arthur E. Jacobson, Staff Attorney, Operations Law Branch, Regulations and Enforcement Division; Richard C. Beitel, Manager. It has been coordinated with the Manager, Air Transportation Division, and the Manager, General Aviation and Commercial Division, Flight Standards Service.
We hope this satisfactorily answers your questions.
Sincerely,
Donald P. Byrne
Assistant Chief Counsel
Regulations and Enforcement Division
