Vectoring to the Initial Approach Fix
In this lesson we will be discussing how to vector an aircraft to the Initial Approach Fix (IAF) or Intermediate Fix (IF). Lets start by looking at the PTAC acronym and how it is used when vectoring aircraft to the IAF/IF.
- P (Position) - The "P" portion of the PTAC is not required when vectoring aircraft to the IAF/IF.
- T (Turn) - When vectoring to the IAF/IF, as opposed to issuing a turn, we will send them direct. If you recall from Introduction to Vectoring there are two ways to send an aircraft direct a fix depending upon the equipment they have on board.
- If they have area navigational capabilities (RNAV) then you can tell them "PROCEED DIRECT (fix/navaid)"
- If they do not have area navigational capabilities (RNAV), then you must vector them to join an airway or a VOR radial or other lateral aid (LOC, NDB etc.) to get them to a fix (if applicable) or provide a heading to fly until they are able to proceed direct a navaid.
- A (Altitude) - This is the altitude that the aircraft is to maintain until established on a published segment of the approach. This is necessary to ensure appropriate terrain/obstacle separation.
- C (Clearance) - This is the clearance for the approach.
Now that you understand the PTAC components, let's look at the phraseology for each:
- T - "PROCEED DIRECT (fix)" or "(turn/fly) (left/right) HEADING (heading), PROCEED DIRECT (navaid) WHEN ABLE" or "(turn/fly) (left/right) HEADING (heading). JOIN THE (radial) DIRECT (fix)". You will want to use whichever situation applies.
- A - "CROSS (fix/navaid) (at or above/at/at or below) (altitude)". Again use whichever situation applies. You'll determine which applies by looking at the chart.
- C - "CLEARED APPROACH"
- If you wish a particular type of approach to be flown, then you must state the type of approach. "CLEARED (type) APPROACH"
- If there is more than one approach of any particular type (such as ILS23 and ILS14) then you will need to specify which approach the pilot will fly. "CLEARED (type)(designator) APPROACH"
- Finally if they are flying an approach into a satellite or uncontrolled field, you will need to state the airport in which the procedure is located. "CLEARED (optional: Type/designator) APPROACH INTO (airport)"
Let's look at some examples. Remember that the procedure is the same regardless of the type of approach.
Scenario #1 - Skyhawk N5204N is a C172/A. He requested to be vectored for the VOR Runway 24 Approach into Cincinnati-Blue Ash (KISZ). He is located at the red "x". Let's look at this procedure and gather some information.
What we can tell from the chart - Looking at this chart, we can see that the Initial Approach Fix is ICING (blue box). We know this because it is labeled IAF. We also know that according to the chart the Minimum Safe Altitude (MSA) around CVG is 3,000 (Green Box). We will be sure not to descend him below that altitude. We see in the vertical profile section that he is to cross icing AT OR ABOVE 3000 (Orange box). Let's take this information and issue his approach clearance.
- T - In this instance he is a "/A" aircraft meaning he does not have area navigation capability. Therefore, sending him direct the fix using the phrase, "PROCEED DIRECT" will not work. Since he is "/A", and the IAF is an intersection, we cannot instruct him "FLY HEADING (heading) PROCEED DIRECT ICING WHEN ABLE". The only option is to have him join the Cincinnati 051 radial direct ICING. Our phraseology will be, "Skyhawk N5204N, Turn right heading 030. Join the Cincinnati 051 radial outbound direct ICING". This satisfies our need to send him direct the IAF.
- A - The chart also indicates he is to cross ICING at or above 3000, so we will just repeat this. "Cross ICING at or above 3000".
- C - Now we issue the approach clearance. Cleared VOR runway 24 approach into Cincinnati-Blue Ash".
So the full clearance would be:
"Skyhawk N5204N, Turn right heading 030. Join the Cincinnati 051 radial outbound direct ICING. Cross ICING at or above 3000. Cleared VOR runway 24 approach into Cincinnati-Blue Ash. Report procedure turn inbound."
Scenario #2 - Learjet N838OM is a LJ45/Q. He is being vectored for the VOR Runway 36 Approach into Ocala International (KOCF). He is located at the red "X".
What we can tell from the chart - Looking at this chart, we can see that the Initial Approach Fix is the Ocala VORTAC (blue box). We know this it is labeled IAF. We also know that according to the chart the Minimum Safe Altitude (MSA) around OCF is 2500 (Green Box). We will be sure not to descend him below that altitude. We see in the vertical profile section that he is to cross OCF AT OR ABOVE 1700 (Orange box). Let's take this information and issue his approach clearance.
- T - He is a /Q aircraft which means we can send him direct the fix using the phrase "PROCEED DIRECT". Therefore our phraseology will be, "Learjet N838OM, Proceed direct the Ocala VORTAC."
- A - According to the altitude on the vertical section, he is to cross the VORTAC at or above 1700. Therefore we will instruct him to "Cross Ocala at or above 1700."
- C - Now we clear him for the approach. Ocala is an uncontrolled airport with multiple types of approaches. Our clearance phraseology will be, "Cleared VOR runway 36 Approach into Ocala International"
"Learjet N838OM, Proceed direct the Ocala VORTAC. Cross Ocala at or above 1700. Cleared VOR Runway 36 approach into Ocala International. Report procedure turn inbound."
Note: In this situation the Lear would also be required to execute a procedure turn since he is approaching from the north.
The hardest part about vectoring to the IAF is understanding the chart. Once you understand the chart and how to read it, determining what to say to clear an aircraft for the approach is easy. In the next lesson, you will learn about vectoring an aircraft to the final approach course.