Procedure turns (por Ed Williams).

La forma más normal de establecerse en una aproximación final es via vectores. El ATC le dará vectores para interceptar el localizador (LOC) con un ángulo de 30º. En caso de que no exista radar disponible Ud. tendrá que hacer un procedimiento de viraje. Este procedimiento será ejecutado desde el marcador externo OM (Outer Marker) o algunas veces desde un radial y a distancia de un VOR.

Observe en la carta de IAL para la pista 21 de ESGG. No existe radar disponible y Ud. tendrá que hacer un procedimiento de giro sobre NL para establecerse sobre el localizador (LOC) pra la pista 21.

Existen un par de cosas importantes que observar. En la esquina inferior derecha figura el MSA (Altitud Mínima del Sector). Esta es la altitud que le dará una separación de 1000ft con el terreno dentro de las 25NM desde el centro de la ayuda (en este caso NL). Esta es la altitud más baja a ser utilizada (IMC) hasta que Ud. este estabilizado en el procedimiento. En este caso 3200ft.

El camino/linea rojo desde NL es el procedimiento de viraje y para establecerse sobre NL Ud. deberá volar dentro del sector azul. Con frecuencia es mejor volar hacia el VOR de LAV y virar al tramo/pierna de acercameinto de NL (cuando este dentro del sector azul). De otra manera también es posible hacer una entrada normal al circuito (la misma forma como si estuviera dentro de un patrón de espera), pero esto con frecuencia tomás más tiempo.

Cuando Ud. esté sobre NL, vire a la izquierda a 30º fuera del recorrido (HDG 355º) por 1 min 30 segundos. El tiempo en la pierna de alejamiento es de dos minutos. Para mantenerse dentro del sector libre de obstáculos vire al trayecto paralelo de 025º en los últimos 30 segundos. Luego vire a la derecha para interceptar normalmente con rumbo de 30º el Localizador (HDG 175º) y continúe en la aproximación normal del ILS.
Luego de pasar NL (en la pierna de alejamiento) Ud. es libre para descender a 3000ft.

Es esencial mantenerse del lado derecho del Localizador durante este procedimiento. De otro modo Ud. no está seguro de estar en un sector libre de obstáculos. También es esencial mantener la velocidad reducida dependiendo del tipo de avión pero las velocidades de un MD80/B737 están alrededor de los 180kts.

Recuerde la dirección del viento y compense.

Procedure Turns

A procedure turn is the maneuver prescribed when it is necessary to perform a course reversal to establish the aircraft inbound on an intermediate or final approach course. The procedure turn or holding in lieu of a procedure turn is a required maneuver. The procedure turn is not required when the symbol "NoPT" appears, when radar vectoring to the final approach, when conducting a timed approach, or when the procedure turn is not authorized.

Course reversals included in an Instrument Approach Procedures are depicted in one of three different ways, 45/180 degree procedure, a holding pattern, or a teardrop procedure. The maneuvers are required when it is necessary to reverse direction to establish the aircraft inbound on an intermediate or final approach course. Components of the procedure are depicted in the plan view and the profile view. The maneuver must be completed within the distance and at the minimum altitude specified in the profile view:

When you see the PT "barb," pilots discretion what type of course reversal to fly. But fly the side of the outbound course indicated.

A procedure turn barbed arrow indicates the direction or side of the outbound course on which the procedure turn is made. Headings are provided for course reversal using the 45 degree procedure turn. 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. Some of the options are the 45/180 procedure turn itself, the racetrack pattern, the teardrop procedure turn or the 80/260 course reversal.

The absence of the procedure turn barbed arrow in the plan view means indicates that a procedure turn is not authorized for that procedure. A maximum procedure turn speed of not greater than 200 knots KIAS should be observed when turning outbound over the IAF and throughout the maneuver to ensure staying within the obstruction clearance area. The normal procedure turn distance is 10 NM. Descent below the procedure turn altitude begins after the aircraft is established on the inbound course.

Standard Procedure Turn 45/180 Standard 45/180 Procedure Turn

To practice this turn other than as part of an approach, start timing at A for 2 minutes from A to B. At B, turn 45 degrees (standard rate). After roll-out, fly 1 minute to C.

At C, turn 180 degrees. At completion of the turn, time 45 seconds from D to E. Start turn at E for 45 degree change of heading to reciprocal of heading at beginning of maneuver.

If you are flying the procedure turn as part of an IAP, you would begin this turn at your discretion after passing the outbound waypoint as charted, then once inbound, watch the CDI or ADF so that you roll out on the inbound course.

Holding in Lieu of Procedure Turn

A holding pattern in lieu of a procedure turn may be specified for course reversal in some procedures. In such cases, the holding pattern is established over an intermediate fix or a final approach fix (FAF). The holding pattern distance or time specified in the profile view must be observed. Maximum holding airspeed limitations as set forth for all holding patterns apply. The holding pattern maneuver is completed when the aircraft is established on the inbound course after executing the appropriate entry (see Holdings for detailed instructions on flying a holding). If cleared for the approach prior to returning to the holding fix, and the aircraft is at the prescribed altitude, additional circuits are not necessary nor expected by ATC. If pilots elect to make additional circuits to lose excess altitude or to become better established on the course, it is their responsibility to advise ATC upon receipt of their approach clearance. When holding in lieu of a procedure turn, the holding pattern must be followed, except when radar vectoring to the final approach course is provided or when NoPT is shown on the approach course.

Teardrop Procedure Teardrop Procedure

When a teardrop procedure turn is depicted and a course reversal is required, unless otherwise authorized by ATC, this type of procedure must be executed. The teardrop procedure consists of a departure from an IAF on the published outbound course followed by a turn toward and intercepting the inbound course at or prior to the intermediate fix or point. Its purpose is to permit an aircraft to reverse direction and lose considerable altitude within reasonably limited airspace. Where no fix is available to mark the beginning of the intermediate segment, it shall be assumed to commence at a point 10 NM prior to the FAF.

At B, enter a standard-rate turn for 30 degree change of heading. Time one minute from B to C. At C, enter standard-rate turn for a 210 degree change of heading, rolling-out on the reciprocal of the original entry heading. As usual, intercept the inbound course based on the CDI or ADF.

For practice, you'll find a teardrop procedure on the ILS 12 at KSMX. IAPs with a holding in lieu of a procedure turn include the ILS 30 at KLGB, the ILS 19R at KSNA and the VOR or GPS-A at KVNY.

You can find these charts at MyAirplane.com.

Lastly, you can see the "barbed arrow" on the VOR/DME or GPS-B at KVNY and the VOR or GPS RWY 25 at KSBA, and just about any other approach that is not holding or teardrop. Enjoy!