Friday, December 12, 2008

Holding Procedures by Joe Echo-Hawk CFII / MEI - www.touch-n-goes

Holding Procedures for IFR

 


What are Holding Patterns used for?

    Holding patterns are parking spots for airplanes.  They are used most frequently by ATC when a particular airport or airspace has an abundance of arrivals or departures causing ATC to need an orderly way to delay traffic while the proper separation is created.


What do holding patterns look like?


Red Dot=Holding Fix, Inbound leg and Outbound leg depicted by arrows.



Executing holding procedures precisely can be more difficult than it first appears.  Here are a few tips and guidelines for helping you fly holding patterns precisely and professionally.  You do not need to buy any holding pattern computers or any other gimmicks.  Holding can be done with nothing more than the pen you use to write down your clearances.


How are Holding Patterns assigned?

Holds are assigned either by the procedures outlined in approach charts or enroute charts or by ATC directly.  The following could be how ATC may assign a hold:

Portland Approach:  Hold on the Newberg VOR 090° Radial with left turns.


How do I enter a Holding Pattern?

There are 3 main recommended holding pattern entries outlined in the FAR/AIM.  Direct entires, teardrop, and parallel entries are standard practice.


            

        Direct         Parallel         Teardrop


Depending on the type of entry you will use, the following procedures can be used to execute the hold entry.


Direct Entry:

- Upon reaching the holding fix, turn in the direction of assigned turns to the heading for your outbound leg.

- Fly this leg for 1 minute and than turn in the direction of turns assigned to the heading for your inbound leg and intercept your assigned holding radial.


Parallel Entry:

- Upon reaching the holding fix, turn to parallel the inbound course on an outbound heading for 1 minute.  

- After 1 minute, turn toward the protected side (holding area) and intercept the holding radial inbound on an inbound heading.  Upon reaching the fix, begin holding procedures.


Teardrop Entry:

- Upon reaching the holding fix, turn 30° toward the protected side (holding area) and fly for 1 minute.

- After 1 minute, begin a turn back to intercept the assigned holding radial inbound to the holding fix.


Please review the diagrams of the different holding entries now that you have read the explanations.


How do I pick which holding entry to use?

There are many different methods for this and all sorts of holding pattern computers you can buy.  I've found one method that works for determining entries and you can do it quickly.  After a little practice you can determine a holding entry in seconds and not be bogged down or distracted in the cockpit while you have more important matters to worry about.


The following steps only work if you are established tracking towards the VOR where your assigned hold begins and you are on a heading that is holding your radial.


Step #1: Draw the hold

Avoid drawing this on paper!  Drawing the holding pattern assigned on paper causes more distractions in the cockpit than is necessary.  A better method I have found is to draw the assigned hold directly on the face of the VOR indicator with your finger. 

Example:  Portland Approach assigned a hold on the 090° Radial, right turns.

- Start with your finger on the outer edge of the VOR indicator at 090° and draw a straight line to the center of the indicator.The "doughnut" in the center of the VOR indicator represents the VOR or holding fix.  

- Upon reaching the fix or "doughnut" turn in the direction assigned, in this case to the right.  If you continue to draw the holding racetrack holding patter you can determine what the holding patter looks like in front of you as you track TO the station.

- Remember: As you track TO the station, by looking at what radial is centered up at the bottom of the VOR indicator you can read which radial you are established on.  By drawing the hold as described in the above method, you can see your position in relation to the holding pattern and increase your situational awareness as you approach the holding fix.  

* It sounds complicated but a few minutes of practice or a demonstration by someone who understands it will prove its complexity a myth.*


Step #2: Determine the type of Holding Entry to use.


For this, bisect the Directional Gyro in the following method.  


 

- To help envision the above pattern on the face of the DG, just use a pen and hold it across the face of the instrument at an approximate 45° angle.  The high side of the pen goes to the right of the instrument for right turn holds and then to the left of the instrument if they are left turn holds.  All you are doing is bisecting the instrument to show you what pattern you will use to enter. 

- After you have done this, look at where your assigned radial falls and depending on which section it is, this is what hold entry you will fly.  To return to the example, if when you hold your pen up to the DG and 090° falls into the Teardrop slice, you will fly a Teardrop entry.  Or, if it falls into any other category, you will fly the associated entry procedure.


  


To enter the holding pattern:

1.  Draw the hold.

2.  Determine the type of entry required.

3.  Determine the heading to turn to and the direction of turns for entering the holding pattern.


-  When you are 3 minutes from your holding fix, slow to your holding speed.  This rule is meant more for turboprops and jets that can exceed maximum holding speeds.  However, it is a good habit to practice even in GA aircraft.  Slowing a Cessna 172 from 100kts to 85-90 kts creates a more economic fuel burn and establishes a good habit for aspiring corporate and airline pilots.

-  The general practice for holding patterns in GA aircraft are inbound legs of 1 minute.  Your outbound leg length should be adjusted accordingly to compensate for wind so that the result is an inbound leg of 1 minute.

-  Wind correction angle on the outbound leg is roughly 3x that of the wind correction angle on the inbound leg.  For example, if you are maintaining 10° of wind correction on the inbound leg to hold the VOR radial, you will need approximately 30° of wind correction into the wind on the outbound leg so that as you turn inbound you will not be undershooting or overshooting your holding radial by a substantial amount.

-  This one is important!!  Never accept a holding clearance without and EFC (Expect Further Clearance) time.  What would happen if you did?  If you lost radio communications while you are in your hold you need an EFC time in order to know when to proceed further with the flight.  If you do not have an EFC time how will you know when to proceed from the hold?