The Vectored Approach

The “vectored approach” is the most commonly flown instrument approach at larger airports.  The requirement for a vectored approach is that the controller be equipped with radar and that the instrument approach has a published “straight-in” procedure.  During a vectored approach, the controller effectively tells the pilot where to point the aircraft—i.e., the heading to fly—and what altitude to maintain (the only occasion where this responsibility for terrain avoidance is technically shared between pilot and controller).

Vectoring is provided by the terminal controller—in the case of both Abbotsford and Victoria, the controllers are referred to as Victoria Terminal.1  A terminal controller keeps close tabs on the weather and traffic conditions at the airports in the sector, and has a direct communications line with each Tower Unit; the basic function of the terminal controller is to facilitate the movement of aircraft in and out of airports with high traffic volumes.

In general terms, a vectored approach is either offered by the controller or requested by the pilot.  Once there is agreement, the controller issues a formal radio clearance which states the function of the “vectoring,” and then subsequently issues a series of headings and altitudes that the pilot must acknowledge and fly.  The first communication is typically as follows:



“Victoria Terminal, this is Piper Cherokee GABC . . .  over Birch Point at 2500 feet’.   Requesting (simulated) vectors for the ILS 07 at Abbotsford.  We have information CHARLIE.”



“ABC Squawk 4312.  . . . Radar identified.  Climb to maintain 3000.  Vectors for the ILS 07 at Abbotsford, turn to a heading of 340°  (Maintain VFR at all times).”

By the time the request is made by the pilot, the ATIS should have already been copied and the appropriate approach plate selected and displayed on the control column or kneeboard—once the vectoring begins, it can be only minutes until the final approach track is intercepted and the pilot must revert to radio navigation indications displayed in the cockpit, whether the ILS or the NDB.  Because IFR conditions exist or are being simulated, the clearance must be copied and “read back” to the controller:



“Vectors for the ILS 07 at Abbotsford.  Maintain 3000’.  Turn to a heading of 340° (Maintain VFR at all times).  GABC”




Note the readback here, and in particular the pattern of simply repeating the clearance and then adding the aircraft identification at the end.

The vectoring procedures typically consist of a minimum of two “legs,” the first of which takes the general form of the VFR “base leg,” and the second is best described as an angled “intercept heading.”  The intercept heading is usually about 30° from the final approach track, allowing the pilot to smoothly transition to the final approach course, whether a track defined by ADF, or the ILS localizer—the idea of a gradual intercept is to avoid excessively rapid movements of the radio navigation indication (localizer or ADF needle).  Here are the basic ATC vectors that comprise a Vectored approach:


The Vectored Approach, Langley Flying School.

During the vectoring phase, and preferably prior to the “intercept heading,” the pilot has two cockpit tasks that must be completed—“brief” the approach plate, and conduct the pre-landing checklist.  The rule of thumb is that all tasks that are extraneous to the actual instrument flying of the aircraft should be completed by the time the aircraft reaches the localizer intercept—once on the localizer and glideslope, pilot attention will be highly taxed.

A useful acronym to remember is SNAP.

The turn onto the intercept heading is associated with additional instructions from the controller.  The controller will advise you that the heading will intercept the final approach course, and it is therefore implied that you will pick-up and track the localizer using pilot navigation.  The intercept heading instruction is also associated with a “straight-in” clearance, and usually a reference to the distance of the aircraft from the final approach fix.



“ABC, turn right heading 020° for the intercept.  Cleared straight-in ILS 07 at Abbotsford.”



“Right to 020 for the intercept, cleared straight-in ILS 07, ABC.




“ABC you are 6 miles back from the beacon, contact tower now on 119.8.  So long.”



“Over to 119.8 now.  So long.  ABC.”

The pilot would then change frequency to the Tower Unit and advise it of the aircraft’s position:



“Abbotsford Tower, this is ABC with you on the ILS 07.  We have Information Charlie.  Request the option.”3



“ABC, AbbotsfordTower.  Roger.  Report Beacon Inbound.”4



“Report Beacon Inbound, ABC.”

The reference to “beacon inbound” means that the pilot must report when the aircraft has passed the final approach fix (Abbotsford NDB, in this case) inbound on the final approach track.

Once you are established on the final approach course outside the FAF, you can safely descend to the FAF crossing altitude on your own accord.5

For an ILS, you generally want to maintain your altitude until glideslope interception is achieved—you then “ride” the glideslope to the DH.

Crossing the FAF, a timer is started and a descent is initiated to the MDA.  The MDA and final approach track is maintained until the runway is spotted visually, or the time to the missed approach point (MAP) is achieved.

Meanwhile, you will be busy on the dials guiding the aircraft down the ILS “slide.”  When you cross the Final Approach Fix, the communication is as follows:



AbbotsfordTower, ABC is Beacon Inbound.”



“ABC is cleared the option, Runway 07.”6



“Cleared for the option, Runway 07, ABC.”



1 Note that the name is the same for both of these airports, but the controller frequencies are different, indicating different “sectors” within the same Terminal Control Unit—see the approaches attached below.

3 The option is requested in this case; your Instructor will advise you as to the type of runway clearance to request—e.g., option, touch-and-go, or low-approach.  In the case that your Instructor wishes you to fly a “low-approach” only, this implies that you will fly down to the minimum altitude as published—in the case of an ILS approach, this is the Decision Height (or “DH”), while in the case of a “non-precision” approach (such as the NDB 07 or the Localizer 07), the minimum altitude is the MDA.

4 Reference here to “the beacon” implies the NDB—in this example, the Abbotsford NDB, which is also the Final Approach Fix for the ILS 07 approach.

5 Once “cleared for an approach” by ATC (assuming no restrictions), the pilot is solely responsible with respect to altitude.

6 In the event that you are following traffic, the controller will provide you with your sequence number here; if this is the case, the controller will also provide you with a subsequent runway clearance (option, touch-and-go, low approach, etc.).