How to spot holding patterns on a flight tracker: reading holdings like a pro

You look at the live map, and suddenly three or four aircraft are flying the same oval loops over a point somewhere in front of the airport – each at a different altitude. That is no coincidence and no cause for concern, but a holding, a holding pattern. If you can spot holding patterns on a flight tracker, you can read a lot from them: how busy the approach is right now, whether a thunderstorm is slowing operations and when the landings will be coming at the fence every minute again. This guide explains the shape, rules and causes of holdings and shows which holding patterns are known at DACH airports (Germany, Austria, Switzerland).

Spotting a holding pattern: the short answer

You recognize a holding on the live map by an oval, racetrack-shaped track over a fixed point. The aircraft flies a turn, a straight leg, another turn and a straight leg back to the starting point – and repeats that until air traffic control clears it for the approach. If several aircraft are affected, they circle above one another in what is called a stack, each at its own altitude. The track differs clearly from a full circle, a deviation around a thunderstorm or the traffic patterns of small aircraft.

Three features are usually enough for a diagnosis:

• Shape: two parallel straight legs, joined at the ends by half circles, over the same spot again and again.
• Altitude: constant over a lap, in a stack gradually falling in steps.
• Speed: noticeably slower than at cruise, because maximum speeds apply in holdings.

How a holding is built

Every holding pattern hangs on a holding fix. In the past that was almost always a radio beacon such as a VOR or NDB; today it is often a pure waypoint with a five-letter name, which modern navigation systems fly to by satellite or radio navigation. From the fix, an inbound direction is defined, the so-called inbound course. The aircraft overflies the fix, turns 180 degrees, flies the leg leading away (outbound), turns again and flies the inbound leg back to the fix.

The key data under ICAO standards:

Feature	Standard	What you see on the map
Direction of turn	Right turns	Track turns clockwise; left-hand holdings are possible if published that way
Leg length up to 14,000 ft	1 minute	compact oval
Leg length above 14,000 ft	1.5 minutes	slightly longer oval
Turns	Standard rate turn, about 3 degrees per second	Half circle in about one minute
Lap time	approx. 4 minutes (low), approx. 5 minutes (high)	regular return to the fix

In wind, crews adjust the time on the outbound leg so that the inbound leg keeps its prescribed length. On the map the oval therefore sometimes looks skewed or uneven in width – that is normal. During long waits, air traffic control can also assign longer legs or distances in nautical miles; the ovals are then stretched accordingly.

Maximum speeds in the holding

To keep aircraft inside the protected airspace around the fix, speed limits apply. Under ICAO these are 230 knots up to 14,000 feet, 240 knots between 14,000 and 20,000 feet, 265 knots above that up to 34,000 feet and Mach 0.83 higher still. Individual procedures can prescribe lower values, and other regions – such as the US – have different tables. On the flight tracker you can therefore often recognize a holding simply because a jet that was moving along briskly a moment ago becomes much slower without descending.

The three entry procedures

How an aircraft joins the loop depends on the direction it comes from. There are three variants that you can sometimes make out well on the first lap:

• Direct entry (Direct): The aircraft overflies the fix and turns straight into the loop.
• Parallel entry (Parallel): It first flies outward parallel to the inbound course, then turns back and intercepts the inbound course.
• Offset entry (Teardrop/Offset): It flies at an angle into the protected area, turns after about a minute and returns to the inbound course. The track then looks like a teardrop.

The first lap is therefore often irregular; the clean oval only forms afterward.

The stack: first come, first held on top

When traffic is heavy, a holding becomes a stack. New aircraft join at the top, and the aircraft on the lowest level is cleared for the approach first. As soon as a level becomes free, the aircraft above descend one step. The levels are usually separated by at least 1,000 feet. On the live map you see this as several ovals exactly on top of each other whose altitude readings differ in steps of a thousand.

The best-known example in Europe is London Heathrow Airport. There are four stacks there named Bovingdon, Biggin, Lambourne and Ockham – one for each quadrant. According to the airport, they have been in the same places since the 1960s. If you look at a flight tracker map over London in the evening, you often see several ovals at once.

Why aircraft have to enter a holding pattern

A holding is a buffer: air traffic control needs a place where it can park aircraft when it cannot get them onto the runway immediately. The most common causes:

Cause	Typical situation	What else you see
Traffic peak	Arrival wave at the hub, e.g. early in the morning	short holdings, few laps, many aircraft at once
Thunderstorm	Cells in the approach area or over the airport	detours on the map, holdings at several points, sometimes diversions
Fog / poor visibility	Approach procedures with greater spacing	reduced landing rate over hours, notes in METAR and TAF
Winter operations	Snow clearing or de-icing of the runway	all approaches stop at the same time for a while
Runway closure	Inspection, malfunction, emergency on the runway	abrupt pause in the approach stream
Runway direction change	Wind shifts, approaches are switched over	brief gap, then approach from the other direction

The fastest way to check the weather is through the airport reports: how to read METAR and TAF is explained in the guide METAR and TAF for spotters. And why a wind shift switches the whole approach stream is covered in Understanding the runway direction in use at an airport.

Modern air traffic control tries to avoid holdings wherever possible. Arrival planning systems distribute delays early, for example by flying more slowly en route or by later departure times at the departure airport. Holdings are therefore today mainly a tool for peaks and disruptions and not the normal case – at large hubs, though, they are part of everyday life.

Well-known holdings at DACH airports

Holding patterns are closely tied to the approach routes. The standard arrival routes (STAR) lead from the airways to certain points at the edge of the approach area, and that is exactly where the holding points often are. How STARs are built is explained in the article SIDs and STARs explained. The following information comes from publicly available sources and can shift with every procedure change – only the current aeronautical information publications of the air navigation service providers are binding.

Munich: four corridors, four holding points

At Munich Airport the approach routes end at four points, each assigned to a quadrant. If an aircraft gets no further clearance, it waits there in the published holding:

Holding point	Traffic from	Assigned runway
ROKIL	Northwest	North runway (08L/26R)
LANDU	Northeast	North runway (08L/26R)
BETOS	Southwest	South runway (08R/26L)
NAPSA	Southeast	South runway (08R/26L)

For spotters this is practical: if you see ovals at ROKIL or LANDU, the aircraft will more likely come in on the north runway later; at BETOS and NAPSA more likely on the south runway. Air traffic control can change the actual runway assignment at any time, though. A good place to see the landings that follow is the Munich Airport visitors’ hill (Besucherhügel); more locations are collected in the plane spotting guide to Munich.

Zurich: GIPOL, AMIKI and RILAX

At Zurich Airport three holdings are published. By their inbound courses, GIPOL lies west and AMIKI east of the airport; RILAX lies in the north over southern German territory. RILAX is therefore explicitly mentioned in a German-Swiss state treaty signed in 2012 on the effects of Zurich airport operations, which Germany did not ratify – among other things it provided for using it only exceptionally at certain times and in coordination with the DFS (German air navigation service provider). That shows how political holding patterns can be: where aircraft circle, noise arises, and in the border area between Switzerland and southern Germany that has been a contentious topic for years. For the landings afterward, the Butzenbüel is a good choice; more on that in the plane spotting guide to Zurich.

Frankfurt and Vienna

At Frankfurt Airport and Vienna Airport as well, air traffic control works with holding points at the edge of the approach area where the standard arrivals begin. In Frankfurt the situation is especially dense because of the parallel runway system and the high number of approaches; holdings occur there mainly during arrival waves, thunderstorm conditions and winter operations. The exact names and locations of the holdings are best taken from the current approach charts. How air traffic control is organized in Germany is explained in the article DFS German air traffic control.

Reading holdings on a flight tracker cleanly

With a little practice you spot holding patterns in seconds. These steps help at the beginning:

Keep data quality in mind. Many services show positions from ADS-B reception, in gaps also from MLAT or estimates. A track with jumps or corners can be a coverage problem, not a real flight path. Background on this can be found under MLAT explained and Why an aircraft does not show up on Flightradar. Unfiltered community trackers such as ADS-B Exchange also show aircraft that commercial services hide at the owners’ request.

Holding or something else?

Pattern on the map	Probably	Distinguishing feature
Oval with two straight legs, several laps	Holding	constant altitude, fixed point
single large loop or zigzag before final approach	Radar vectoring	no repetition over the same point
Climb over the runway, then new approach	Go-around	track leads over the runway, altitude suddenly rises
Arc around an area	Thunderstorm deviation	swerves sideways, no oval
Circles over land, low, slow	Police, rescue, survey	very low altitude, no connection to the approach

A go-around sometimes looks similar at first glance but has different causes – more on that in the guide Go-arounds explained.

What holdings mean for your spotting day

For spotters, holding patterns are more than a curiosity on the map. They change what happens at the fence:

• Delayed arrivals: The plane you are waiting for arrives later than the arrivals board shows. Forecasts on flight tracker services do not always account for holdings properly – more on this in the article How accurate are ETA forecasts?.
• Bunches instead of a steady rhythm: After a thunderstorm pause or snow clearing, the stacks dissolve and the landings come close together. Battery and memory card should be ready then.
• Diversions as an opportunity: Long holdings with bad weather at the destination sometimes end in a diversion. How to spot that early is covered in Spotting a diversion live.
• New runway, new spot: If a holding ends because of a runway direction change, the aircraft then land at the other end of the runway. A quick change of spot can be worth it.

What to keep in mind

• A holding is not an emergency. Do not speculate in groups and on social networks about problems on board just because an aircraft is circling. Real emergencies show up more through a transponder code – see Squawk codes 7500, 7600, 7700.
• Circling is not the same as a holding. Calibration flights, training flights, police helicopters and survey aircraft also fly loops. Check type, altitude and flight number.
• Procedures change. Waypoints are renamed, approach routes redesigned. What applied a few years ago does not have to be true today.
• Local rules apply at the spot. If you spontaneously change location because of a stack, you still stay on public paths – emergency access roads and farmers’ field tracks are not part of that.

Conclusion

Holding patterns are the most visible sign of how air traffic control brings order to a full approach. On the flight tracker you recognize them by the oval racetrack shape over a fixed point, by staggered altitudes and by reduced speed. The causes range from the morning arrival wave to a thunderstorm over the airport. If you know where the holding points of your home airport are – in Munich for example ROKIL, LANDU, BETOS and NAPSA, in Zurich GIPOL, AMIKI and RILAX –, you can read from them when and where the next landings will come. The article Holding patterns explained goes deeper into the basics of the procedure itself.