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Reversing Direction for Approach
The procedure turn was part of the radio range system that preceded the VOR NDB, and ILS soon to be phased out by GPS. The radio range sent out four radio beams in four quadrants. An A-N audible tone could be heard to each side of a beam. A was -.; N was .- when you were flying on the beam the tone was steady. Any deviation off course gave either an A or N code indicating the direction required to correct.

At the juncture of the four beams was the null or cone of silence. This told you exactly where you were. From this point you fly outbound on a beam for a timed period, execute a procedure turn, intercept the beam inbound and begin your descent, knowing that you have obstacle clearance back to the null and the airport so long as you stay on the A N beam.
This was the basic instrument procedure used up until the 1950's.

The same course reversal procedure is used at most general aviation airports except when superseded by radar vectors. Any course reversal procedure must be completed within 10 miles of a designated fix usually the FAF. There are three types of full approaches used to turn the plane back into the final approach course. AIM 5-48 NOS chart's barbed arrow indicates only direction/side of outbound course. Point of commencement, type and rate of turn is discretionary.

--1)The standard procedure turn may illustrate a 45-180-45 to final.
--2)A published tear-drop pattern is required as published.
--3)A holding pattern is also required as published. You do not need to make the full loop if your entry allows you to become established inbound
--You may use the "course-reversal" for your procedure turns or holding pattern entries as long as you remain in protected airspace. I find these especially good for ADF approaches.
--On a published IAP any course reversal is mandatory for the pilot unless:
According to FAR 91.175(j)
1. Radar vectors are available
2. NoPT is published on plate
3. A timed approach from a holding fix with tower in operation and timing procedures in use.

Procedure Turns
The procedure turn is prescribed as a method for turning an aircraft around and reversing its course when on the intermediate or final approach parts of an instrument procedure. The approach plate specifies the procedure turn fix, the inbound and outbound course, the distance required for completion and the direction r/l of the turn. The procedure turn is required except when the NoPT is indicated, radar vectors are provided, when a holding pattern is shown in lieu or (rare) with timed approaches. Only teardrop or holding pattern (racetrack)  procedure turns are specifically required.

The necessity for the teardrop comes when a very narrow corridor requires a significant loss of altitude. This procedure is known as a penetration turn due to the space and altitude constraints. To make the intercept from a teardrop it is very important that you know your distance from the FAF. A smooth turn at the nine mile point should give a smooth intercept.

In every other case how the procedure is accomplished within the allotted airspace as well as where to turn and how to turn is discretionary to the pilot. To stay within bounds it is important the descent to the procedure altitude and outbound route be at least "bumped" before beginning the procedure turn outbound. Failure to do this could take you outside protected airspace. You have ten miles from the fix outbound to complete the turn. Allow at least one minute to get established inbound to the fix.

If ATC does not specifically state that you will be given radar vectors, you as PIC can decide if a procedure turn is required. Being cleared for the approach by ATC means that they assume that you know what to do. This includes, that you know you are required to remain above the charted altitudes for the route. How you do it or if you do it is up to you. Remember, if something goes wrong the FAA gets to second guess any decision you make. See FAR 97.3 and AIM 5-48a. Once established inbound you can descend to published inbound altitude. Established means that the intercept needle is at least half way to center. Cleared for the approach does NOT include a clearance to land.

If a descent is required allow a minute for every 500'. Turning from the outbound part of the turn to the inbound part is a required reporting point. The inbound turn leg is when you use the mid-point of any needle deflection to initiate descent to the inbound altitude. You should be in approach configuration with your approach checklist completed as you become inbound to the fix. At the fix use your Ts list. At MDA/DH land or make the missed.

The maneuvering zone is the wide side of the allocated space from the course line for making the course reversal. To the other side of the course line there is a primary area which is five nm wide. Around the whole is a two nm secondary area. You have 8 nm of airspace on the procedure turn side of the course line and 4 nm on the non-procedure side both with at least 1000' of obstacle clearance at assigned altitude. The 10 nm turn requirement distance has 16 nm of protected space. Your knowledge of this available space should reduce the plucker-factor if you overshoot or misjudge wind effect. It is the safest procedure to assure flight to the center of the procedure area.

The turn options that work are, the often published 45-180 which requires diverted attention to timing, an 80-260 (90-270 course reversal) which does not require timing, and the Army 45 (for 40 seconds)-225. In strong crosswind conditions a 260-80 might be preferred with the initial turn into the wind. Get the winds before you make the turn or you had best go as published. When a crosswind exists at the point for the procedure turn the 45 degree outbound leg should be 40 seconds plus lengthened or shortened one second for every degree of wind correction required on the outbound leg.

NOS charts just show an arrow to the turn side. Jeppesen uses the 45-180. Be sure to advise anyone in the cockpit of what you plan to do. Try to use the procedure that will most reduce the effect of the wind. ATC usually requests that you advise when 'procedure turn inbound'.

An ILS should be timed (not timing is not cause for flight test failure) passing the non-precision FAF (Maltese cross). This guarantees positional awareness if the glide slope fails and you need to continue with a localizer-only approach. If the glide slope should fail you can climb but you cannot turn until the localizer time runs out. The obstacle clearance allowances are much narrower on the approach side of the localizer transmitter than on the missed approach (back course side). The FAF for an ILS is the point you intercept the glide slope at the designated altitude on the chart. You can always ask ATC for a marker or fix call or even your position if you are in a radar environment. (See Livermore chart) Every pilot flying an ILS must understand the chart symbology both for a full ILS and for the Localizer approach. There is a difference between a precision FAF and a non-precision FAF.   FAR 91.175(j) and AIM 5-4-8

Procedure turn limits says hearing, ‘Radar vectored to...’ final approach course, or fix, a timed approach from a holding fix, or an approach specifying ‘No PT you cannot make a procedure turn unless cleared by ATC.

Radar vectors will include a crossing restriction. Without the proper clearance you must fly the full procedure. A clearance that is unclear must be challenged for clarification.

Time outbound for two minutes if fix is on airport, three minutes if off the airport. Not an FAR just to keep you inside the protected area. If you can measure distance from the fix, use it. Try to turn inbound to intercept at least one-mile and better 2-miles outside the fix.

The distance for the PT completion is a compromise between the distance needed to change direction and the airspace needed to provide separation. Standard PT completion distance is 10 NM. May be reduced to five for Category A aircraft only procedures and to fifteen when required. Maximum PT speed is 200 knots. GPS area routes are replacing PT.

Calling the Procedure Turn Inbound
The procedure turn inbound occurs at the point when the reversal of the outbound turn has been completed until the inbound course is intercepted. The time of the radio call is used by ATC for air traffic spacing. Get to and track inbound course by correcting wind drift. Get to outbound course by correcting drift CAT check (course, altitude, turn direction) for course reversal.

NoPT (No Procedure Turn)
Procedure turns are charted at most general aviation airports but are more often not required due to radar vectors. The continue charting of the turns is because the possibility of radar failure always exists. Flying the full procedure does train the positional awareness that is frequently lost under radar vectors. Some GPS approaches will have procedure turns to conform to historical practice and no other reason.

There is often confusion as to whether or not a pilot is required to do a procedure turn and confusion on the part of ATC when a pilot performs the maneuver when none is expected. ATC can stop the confusion by making their approach clearances that are expected to be straight in include the term "straight in".

If the procedure turn is published and you are not vectored to the final approach course, you are expected to fly the procedure so as to perform the procedure turn.

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