Anyone been able to find this letter on the FAA site? Looking for a reputable source I can reference.
The Chief Counsel portion of the FAA site only has opinions going back to 1990. The "moonless night" letter is from 1984. I've seen enough reproductions (not photocopies or scans, just the text) from sources I think are reliable but YMMV.
FWIW, here is the full text. Maybe you can use it to find a source you feel comfortable with:
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November 7, 1984
Mr. Joseph P. Carr
Dear Mr. Carr:
This is in response to your letter asking questions about instrument flight time.
First, you ask for an interpretation of Section 61.51(c)(4) of the Federal Aviation Regulations (FAR) regarding the logging of instrument flight time. You ask whether, for instance, a flight over the ocean on a moonless night without a discernible horizon could be logged as actual instrument flight time.
Second, you ask for an interpretation of Section 61.57(e)(2) of the FAR, noting that Advisory Circular 61-65A, Certification: Pilots and Flight Instructors, seems to contain advice contrary to your understanding of the rule.
As you know, Section 61.51(c)(4) provides rules for the logging of instrument flight time which may be used to meet the requirements of a certificate or rating, or to meet the recent flight experience requirements of Part 61. That section provides in part, that a pilot may log as instrument flight time only that time during which he or she operates the aircraft solely by reference to instruments, under actual (instrument meteorological conditions (imc)) or simulated instrument flight conditions. "Simulated" instrument conditions occur when the pilot's vision outside of the aircraft is intentionally restricted, such as by a hood or goggles. "Actual" instrument flight conditions occur when some outside conditions make it necessary for the pilot to use the aircraft instruments in order to maintain adequate control over the aircraft. Typically, these conditions involve adverse weather conditions.
To answer your first question, actual instrument conditions may occur in the case you described a moonless night over the ocean with no discernible horizon, if use of the instruments is necessary to maintain adequate control over the aircraft. The determination as to whether flight by reference to instruments is necessary is somewhat subjective and based in part on the sound judgment of the pilot. Note that, under Section 61.51(b)(3), the pilot must log the conditions of the flight. The log should include the reasons for determining that the flight was under actual instrument conditions in case the pilot later would be called on to prove that the actual instrument flight time logged was legitimate.
To answer your second question, your understanding of Section 61.57(e) is correct. Section 61.57(e) provides currency requirements for acting as pilot in command (PIC) under instrument flight rules (IFR) or in weather conditions less than the minimums for visual flight rules (VFR). No pilot may act as PIC under those conditions unless she or he has, with the last six months, logged the number of hours of instrument flight time, including the number of approaches, indicated in Section 61.57(e)(1)(i) or (ii). When that six-month currency period lapses, that is, on the day the pilot no longer has the required instrument flight time within the last six months, the pilot may in the next six months regain her or his currency simply by logging the required instrument flight time. Note that, during this second six-month period, Section 61.57(e)(1) prohibits the pilot from acting as PIC under IFR or below VFR minimums (imc). If that second six-month period runs without the pilot regaining currency, she or he may only again become qualified to act as PIC under IFR or in weather below VFR minimums (imc) by passing an instrument competency check as described in Section 61.57(e)(2).
Advisory Circular 61-65A, paragraph 15a, explained in part that a pilot failing to meet the recency of instrument experience requirements for a period of 12 months must pass an instrument competency check. This simply meant that, when a pilot becomes qualified to act as PIC under the instrument conditions described, he or she has at least a 12-month period in which currency my be maintained or regained by logging the required instrument flight time. After that 12-month period, if currency has not been maintained or regained, the pilot must pass an instrument competency check. Advisory Circular 61-65A was not intended to expand the second six-month "grace" period to 12 months. As you note, the Advisory Circular has been changed, and paragraph 15 was rewritten to more accurately reflect the requirements of Section 61.57(e)(2).
Sincerely,
/s/
John H. Cassady
Assistant Chief counsel
Regulations and Enforcement Division
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