2.7_ Holds

In short, holding patterns can confuse even the most experienced pilot. There are many different entry procedures into a simple holding pattern. If we tried to explain them all at once, we would get something like this:



Scary, isn't it?

In this section, we will try to explain the basics of a holding pattern. Furthermore, we will illustrate the most common types of entries into a holding pattern and explain when they are used.

2.7.1 The Basic Holding Pattern

A holding pattern are normally to be demanded by ATC because of for instance delays at arrival airport. ATC will give you necessary instructions how to fly to the holding pattern. It can be included in your route or you will be guided via vectors to fly to a specific VOR/NDB/FIX and make a holding. The most difficult with a holding is the entry, because of the 3 different ways to join the holding. A holding normally is drawn on the STAR/SID/IAL charts with a designated inbound heading to the waypoint where the holding will be performed. The basic holding pattern looks like this:



We see that the hold is shaped like an elongated circle. From the diagram, we note:

  1. The hold has both an inbound course (also referred to as the holding side of the pattern) and an outbound course (also referred to as the non-holding side of the pattern).

  2. In most cases, aircraft perform a 180º standard turn immediately after passing the holding fix (in this case, it's a generic VOR). There are some holds where the outbound leg is flown on the holding side of the pattern, but these are rare. Thus, we will stick to what is commonly known as a 'standard' holding pattern here.

  3. A standard holding pattern is 4 minutes long. It consists of 2 1-minute legs, and 2 1-minute 180º turns. upon crossing the holding fix, the aircraft immediately begins the turn. Upon completion of the first turn, a 2-minute outbound leg is then flown, followed by another 1-minute turn to bring the aircraft back onto the correct inbound leg (often the inbound leg is a VOR radial and is tracked inbound. See ">2.2_ Navigational aids for more information on tracking VORs). Also, unless otherwise published, a standard holding pattern is flown at 220 KIAS.

  4. There is an imaginary boundary line that crosses the holding fix at a 70º angle. This line is the separator between the use of a direct entry into the hold and the use of parallel or offset entries as shown below.


Speed Restrictions and Leg Lengths in the Hold

Altitude Time of each leg Max speed
Below FL140 1.0 minute 230 kts
FL 140 - 200 1.5 minute 240 kts
Above FL200 1.5 minute 265 kts


2.7.2 Ways to Enter a Holding Pattern



As labeled in the diagram above, the type of entry an aircraft performs when entering the hold differs based on the direction from which the aircraft approaches the holding fix.



2.7.2.1 Direct Entry into a Holding Pattern



A direct entry to the hold is the most simple of the three. In a direct entry, the aircraft:
  1. Flies direct to the holding fix, or (1a) Flies direct to the holding fix and crosses at a 90º angle (if approaching on the inbound side perpendicular to the holding fix). In the case of step 1a, the aircraft bypasses the first 180º turn, continuing directly to step 3.
  2. Performs a right-hand (unless instructed by ATC) 180º standard rate turn (360º in 2 minutes, thus 180º in 1 minute).
  3. Flies the outbound leg for the set amount of time.
  4. Performs a second right-hand (unless instructed by ATC) 180º standard rate turn to rejoin the inbound leg.
  5. Flies the inbound leg and repeats steps 2-5.


2.7.2.2 Offset (Teardrop) Entry into a Holding Pattern



An offset entry is slightly more tricky than the direct entry, as it involves flying an angled outbound leg on the initial entry into the hold. In an offset entry, the aircraft:
  1. Flies direct to the holding fix.
  2. Upon crossing the holding fix, flies a bearing 30º GREATER than that of the OUTBOUND course (thus with a 142º inbound course, 322º outbound course, the offset leg would be flown on a bearing of 352º). This leg is flown for the same amount of time as a normal outbound leg would be flown.
  3. Turns sharply to intercept the inbound leg and flies an inbound leg until crossing the holding fix on the inbound course
  4. Performs a right-hand (unless instructed by ATC) 180º standard rate turn (360º in 2 minutes, thus 180º in 1 minute).
  5. Flies the outbound leg for the set amount of time.
  6. Performs a second right-hand (unless instructed by ATC) 180º standard rate turn to rejoin the inbound leg.
  7. Flies the inbound leg and repeats steps 4-7.


2.7.2.3 Parallel Entry into a Holding Pattern



A parallel entry is quite possibly the most difficult entry into the holding pattern as it requires a very rapid turn to rejoin the inbound holding leg. In a parallel entry, the aircraft:
  1. Flies direct to the holding fix.
  2. 10 seconds after crossing the holding fix, turns to fly parallel to the inbound leg on the outbound course for the same amount of time as a standard outbound leg would be flown.
  3. Turns sharply to fly direct to the holding fix.
  4. Rejoins the inbound leg approaching the holding fix and crosses the holding fix on the inbound course.
  5. Performs a right-hand (unless instructed by ATC) 180º standard rate turn (360º in 2 minutes, thus 180º in 1 minute).
  6. Flies the outbound leg for the set amount of time.
  7. Performs a second right-hand (unless instructed by ATC) 180º standard rate turn to rejoin the inbound leg.
  8. Flies the inbound leg and repeats steps 5-8.

 

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