I queried them about that a few years ago. I sent them a copy of the Word file of the complete text. Their answer was essentially, "We can't find a signed paper copy, but it appears genuine."

I'll post that full text tonight.
Oh I can do that.... I've had it for about 20 years. Here it is. I can do a Word doc, even a pdf if you like. (I have a funny feeling the Chief Counsel's office wasn't using Microsoft Word in 1977

)
"appears genuine" isn't quite the same as "yes, it is in our database showing it's ours" or even "we don't have it but it's an accurate statement of the rules." Especially since it does not appear in any official or commercial database - not even the $800 set of bound volumes sold to lawyers. I have something similar - I corresponded with Ed Faberman in my effort to track down its authenticity. His comment: "I don't remember it but it sounds like me."
For those interested, here it is.
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June 22, 1977
Mr. Thomas Beane
Dear Mr. Beane:
This letter is in response to your recent letters to the FAA Flight Standards Service and to the Chief Counsel inquiring about the logging of pilot-in-command (PIC) time by an airman whenever he is not the sole manipulator of the controls.
Section 1.1 of the Federal Aviation Regulations defines Pilot in Command as:
Pilot in command means the person who:
(1) Has final authority and responsibility for the operation and safety of the flight; (2) Has been designated as pilot in command before or during the flight; and (3) Holds the appropriate category, class, and type rating, if appropriate, for the conduct of the flight.
Section 61.51(c)(2) of the Federal Aviation Regulations provides, in pertinent part:
(2) Pilot-in-Command flight time.
(I) A private or commercial pilot may log as pilot in command time only that flight time during which he is the sole manipulator of the controls of an aircraft for which he is rated, or when he is the sole occupant of the aircraft, or when he 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.
A pilot may log PIC time in accordance with Section 61.51(c)(2)(I) when he is not actually "flying the airplane", if the airplane is one on which more than one pilot is required under its type certificate or under the regulations under which the flight is conducted and he is acting as PIC.
Also, a pilot, rated in category and class (e.g. airplane single-engine) could, as the pilot who "Has final authority and responsibility for the operation and safety of the flight" log PIC time if another pilot, not appropriately rated, was actually manipulating the controls of the aircraft.
It should be noted that more than one pilot may log PIC time for the same flight time. For example, one pilot receiving instruction may log PIC time in accordance with paragraph (c)(2)(I) for the time he is designated PIC, and another pilot may log PIC time in accordance with (c)(2)(iii) for the same time during which he is actually giving flight instruction.
We hope that we have satisfactorily responded to your inquiry on the proper logging of PIC time.
Sincerely,
ORIGINAL SIGNED BY EDWARD P. FABERMAN
for NEIL R. EISNER Acting Assistant Chief Counsel Regulations & Enforcement Division Office of the Chief Counsel -
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