First and for most important question of this content is why to hold? Reasons of holding are multiple and expected to increase with growth of air traffic. Some common reasons for holding are:
- Aircraft in emergency
- Traffic congestion
- Equipment Outage
- Pilots buying time to make decision or trouble shooting
- Bad weather
- Unavailability of Runway
Holding patter is oval course flown by aircraft when it is holding for any of the above mentioned reasons, traffic congestion remaining most general one. This holding pattern can be published one or can be assigned by air traffic control with sufficient data. Holding pattern is generally defined with respect to a navigation fix. This can be a VOR, NDB or even a way point.
Standard Holding Pattern |
Non Standard Holding Pattern |
| All turns are made to right side once the inbound to the hold is established.
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All turns are made to left side once inbound to the hold is established.
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ENTRIES TO HOLDING PATTERN
Entries into holding pattern sometimes become a complicated task. The reason of this issue is lack of situational awareness, shortage of on board equipment, more work load in cockpit etc. It is one of the hardest part for novice pilot to grasp. Hope the video in this content and the text will help you in understanding the entries.
There are three types of entries: Direct, Parallel and Offset (Tear Drop)
- in figure above complete airspace around the fix has been divided into 4 Zones.
- Zone 1 and 2 are for parallel and tear drop(offset) entry respectively and Zone 3 and 4 are for directly entry collectively
Tear Drop or Offset Entry |
Parallel Entry |
Direct Entry |
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- This video below should make the understanding easy.