If you’ve ever browsed airspace around a busy airport on Flightradar24, you’ve likely noticed aircraft circling in oval, racetrack-like loops. These loops are called holding patterns, and they play a crucial role in air traffic management and flight safety.

What is a holding pattern?

A holding pattern is a standardised racetrack-shaped flight path that aircraft fly while awaiting further clearance from air traffic control (ATC). Aircraft may be instructed to enter a hold when approaching congested airports, during periods of bad weather, or if there’s a need to delay an approach for sequencing or separation.

Each holding pattern is centred around a ‘holding fix’, which is typically a navigational beacon (such as a VOR, NDB, or GPS waypoint). Aircraft fly the pattern at a designated altitude and airspeed until they’re cleared to exit the hold and continue their route.

Why do aircraft enter holding patterns?

Aircraft enter holding patterns for several key reasons:

• Airspace congestion: Busy airports like JFK, Heathrow, or Frankfurt may use holding patterns to manage inbound traffic during peak hours.
• Weather disruptions: Low visibility, thunderstorms, or strong crosswinds may delay landings, requiring aircraft to wait in a hold until conditions improve.
• Runway availability: When runways are temporarily closed due to incidents or snow clearance, aircraft are often placed in a holding pattern.
• Emergencies or technical Issues: Pilots may enter a hold to troubleshoot issues or burn fuel before landing overweight.

In an emergency, aircraft squawk 7700 on their transponder. You can monitor such alerts on Flightradar24 by setting up a general emergency notification.

How do aircraft enter holding patterns?

Before flying a hold, pilots must determine the best entry procedure based on their direction of arrival. There are three standard holding pattern entry types:

• Direct entry: The aircraft flies straight to the fix and enters the pattern.
• Parallel entry: The aircraft flies over the fix, turns outbound on the reciprocal heading for one minute, then turns back toward the holding pattern.
• Teardrop (Offset) entry: The aircraft flies over the fix, turns about 30 degrees off the inbound course for one minute, then turns back toward the inbound leg.