#2 on the original post is absolutely incorrect. ATC does not have the authorization to direct a pilot to not complete a PT or HILO.
That's a question that has never had a clear answer. For example, from a 1977 Chief Counsel opinion on the mandatory nature of a PT (note that the numbers of the pertinent regs have changed)
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However, ATC may "authorize" a deviation from the prescribed procedure when it determines that a different approach procedure is appropriate
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Here's the full opinion:
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July 25, 1977
Robert E. Little, Jr., Esquire
Dear Mr. Little:
We have reviewed your letter dated April 28, 1977, in which you requested an interpretation concerning whether, when depicted on an approach chart, a procedure turn is required under all circumstances in executing an IFR approach or it is permissive and subject to the pilot's judgment as to the need for the maneuver. Our conclusion is essentially as discussed with you on the phone on May 17, 1977.
In your letter, you indicated that during the first leg of an IFR training flight from Tipton Army Air Field, Fort Meade, Maryland to Westminster Airport (EMI), you were radar vectored to Federal Airway V-265 and thereafter maintained an altitude of 3,000 feet. Approximately 4 miles south of Westminster VORTAC you obtained the following Air Traffic Control (ATC) clearance:
"Army 295, radar service terminated 4 miles south of Westminster VOR, cleared for the VOR approach at Westminster, maintain 3000 feet until crossing the VOR."
You indicated that "for training purposes" you executed a procedure turn during the approach but concluded, after discussion with your instructor pilot, that the procedure turn was not required under the Federal Aviation Regulations (FARs). You stated that you considered the following factors:
"(1) Our course was 11 to the right of the final approach course depicted on the plan view of the Westminster VOR Runway 36 approach;
(2) We were only 500 feet above the minimum procedure turn altitude; and
(3) We had approximately 4 minutes and 30 seconds to lose approximately 1500 feet at a rate of approximately 330 feet per minute after crossing the EMI VOR."
According to your letter, your subsequent research into the matter and
inquiries of various FAA personnel into the correctness of your conclusion did not provide a satisfactory answer.
As you discovered, "procedure turn," as a symbol or term used in Part 97 of the FARs, is defined in Section 97.3(p) as follows:
"(p) Procedure Turn means the maneuver prescribed when it is necessary to reverse direction to establish the aircraft on an intermediate or final approach course. The outbound course, direction of turn, distance within which the turn must be completed, and minimum altitude are specified in the procedures. However, the point at which the turn may be commenced, and the type and rate of turn is left to the discretion of the pilot." [Emphasis added]
Pertinent paragraphs of Section 91.116 "Takeoff and landing under IFR; General" provide as follows:
(a) Instrument approaches to civil airports. Unless otherwise authorized by the Administrator (including ATC), each person operating an aircraft shall, when an instrument letdown to an airport is necessary, use a standard instrument approach procedure prescribed for that airport in Part 97 of this chapter.
(h) Limitations on procedure turns. In the case of a radar initial approach to a final approach fix or position, or a timed approach from a holding fix, or where the procedure specifies "NOPT" or "FINAL", no pilot may make a procedure turn unless, when he receives his final approach clearance, he so advises ATC.
Paragraph (a) of Section 91.75 "Compliance with ATC clearances and instructions" states in pertinent part as follows:
(a) When an ATC clearance has been obtained, no pilot in command may deviate from that clearance, except in an emergency, unless he obtains an amended clearance. ... If a pilot is uncertain of the meaning of an ATC clearance, he shall immediately request clarification from ATC."
Accordingly, under Section 91.116, Part 97 Standard Instrument Approach Procedures (SIAPs) are regulatory and, unless otherwise authorized (such as by an ATC clearance to the contrary), a pilot is required to execute an IFR approach in accordance with the SIAP prescribed in Part 97. As you know, the substance of SIAPs is reflected on "approach plates" or other flight information available for use in the cockpit.
Particular SIAPs may prescribe a procedure turn that is mandatory, permissive, or prohibited depending on the application of criteria contained in the U.S. Standards for Terminal Instrument Approach Procedures (TERPs). The TERPs are used by the FAA in developing SIAPs for particular regulatory approaches at particular airports. However, ATC may "authorize" a deviation from the prescribed procedure when it determines that a different approach procedure is appropriate. Accordingly, a pilot may request ATC for authorization to deviate from a prescribed procedure turn, if it is prescribed as mandatory or, if it is prescribed as permissive, he may request an approach clearance with or without the described procedure turn.
Thus, if you accepted the indicated ATC clearance, under the FARs, you were requested to maintain an altitude of 3000 feet on the inbound course until crossing the VOR and then to execute the prescribed (SIAP) VOR approach at Westminster. Since the (SIAP) VOR approach prescribes a mandatory procedure turn as part of that procedure, the procedure turn (as described) is required.
Further, please note that if a pilot is uncertain whether the IFR approach procedure for which he obtained ATC clearance requires or only permits a procedure turn, he is required under Section 91.75(a) to immediately request clarification from ATC.
You correctly noted that the discussion of procedure turns in Advisory Circular 90-1A is neither regulatory nor interpretive of the regulation. Advisory circulars, as their title suggests, are intended to provide information, suggestions and other guidance.
If we can be of further assistance, please feel free to contact us.
Sincerely,
NEIL R. EISNER
NEIL R. EISNER
Assistant Chief Counsel
Regulations & Enforcement Division
The underlining was added by me - things haven't changed much.
