How to join a traffic pattern when passing overhead?

Question

I can't seem to find a definite answer to the question on how to enter a traffic pattern when joining from the opposite end of the pattern. No matter who I ask, I'm getting a different answer every time, and they all seem convinced it's the only way to go.

So I'd like to ask a broader audience here.

Let's say runway 36 is in use, right traffic and you approach from the west. How do you enter the pattern?

I'm convinced "B" is the right way (safest at least) but recently I heard an ATC conversation where the pilot was instructed to cross overhead and join downwind. He used method "B" but the controller didn't like that because it took too much time.

What is the correct way? Is there a difference between controlled and uncontrolled airports? What about the procedure when approaching from other angles? And is there a difference between the U.S. and other parts of the world?

EDIT:

On March 13 2018, the FAA released the following Advisory Circular regarding this matter: AC-90-66B.

Answer 1

What is the correct way?
Is there a difference between controlled and uncontrolled airports? What about the procedure when approaching from other angles?

Well I'll address your second quesition first: There is ABSOLUTELY a difference between controlled and uncontrolled fields. At a controlled field you do what ATC tells you to do (and if there's any ambiguity you ask them to clarify what they want you to do).

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At uncontrolled fields in the USA the standard way to enter the VFR traffic pattern is a 45-degree intercept to the downwind leg. The FAA's pronouncements on the issue can be found in AC 90-66A.
A brief and relevant excerpt:

a. Prior to entering the traffic pattern at an airport without an operating control tower, aircraft should avoid the flow of traffic until established on the entry leg. For example, wind and landing direction indicators can be checked while at an altitude above the traffic pattern. When the proper traffic pattern direction has been determined, the pilot should then proceed to a point well clear of the pattern before descending to the pattern altitude.

b, Arriving aircraft should be at the appropriate traffic pattern altitude before entering the traffic pattern. Entry to the downwind leg should be at a 45-degree angle abeam the midpoint of the runway.

(Emphasis Added)

You will find a rich variety of opinions (a polite way of saying "hidebound arguments") among pilots on the correctness of various other entries, but the 45-to-downwind is what's expected by most pilots in the US, and it is generally the safest way to enter the pattern (you will be where everyone else expects you to be, and you will have plenty of time to look at the pattern and figure out how you're going to sequence into it).

The 45-degree intercept assumes that you are on the side of the runway where you will be flying your downwind leg. If you are on the opposite side you need to position yourself to maneuver for a 45-degree intercept. I am personally a proponent of the technique illustrated below:

• Cross midfield 500-1000 feet above pattern altitude.
  • At airports where there are multiple pattern altitudes specified, such as a "jet pattern" above the light aircraft pattern, cross at least 500 feet above the highest pattern altitude to ensure traffic separation.
• Proceed away from the airport and clear of the traffic pattern before descending.
• Make a descending turn to intercept the 45-degree entry
  • Ideally time your turn and descent such that you're at pattern altitude when you intercept the 45-degree track. If you expect to need more time to descend plan for a longer entry.
• Enter the traffic pattern on a 45-degree-to-downwind.

Note that this is subtly different from your "Option B" (which has the descending turn leading directly into the downwind) in order to comply with the advisory circular's instruction that you should be "well clear of the pattern before descending".

^{_{I cribbed the pattern entry graphic from Alliance Airways, with some minor modifications, as it was the best illustration of the technique I could find.}}

Answer 2

This topic can generate a lot of discussion as you've noted, but I think there are some generally accepted conclusions.

The simplest case is joining the pattern at a controlled airport because the procedure in any country is the same: follow ATC's instructions (and ask if they aren't clear!).

For unmanned airports the picture is less clear-cut, at least in the US where you can join the pattern however you like as long as it's safe. The FAA strongly recommends "joining on the 45" which is your option B:

When approaching an airport for landing, the traffic pattern should be entered at a 45° angle to the downwind leg, headed toward a point abeam of the midpoint of the runway to be used for landing. Arriving airplanes should be at the proper traffic pattern altitude before entering the pattern, and should stay clear of the traffic flow until established on the entry leg.

(Your option A looks somewhat risky, because to join right downwind at pattern altitude would mean busting through the left downwind side of the pattern, and it could also be in use by some traffic.)

But this joining method isn't an absolute requirement, and the traffic, terrain, local procedures etc. could require a different entry. Some pilots will even take a straight-in approach, especially in larger, faster aircraft and/or when there's little active traffic. (That's one point of possible controversy.)

Outside the US the procedures or regulations may be different. In South Africa I was taught a specific procedure for "joining overhead" at an unmanned field and (from memory) it was required by law. I've heard (and Wikipedia says) that the UK and some other Commonwealth countries also use it, but I don't have any direct knowledge of that. This is how it works and I was required to demonstrate it during my cross-country flight test:

You circle overhead the field at 2000agl for as long as it takes you to identify the active runway, wind direction, other traffic etc. Then you descend on the "dead side" - i.e. on the opposite side from traffic in the pattern - and cross the runway at the takeoff end at 1000agl before turning downwind.

The idea is that the procedure keeps you above pattern altitude for as long as possible to give you better visibility and more options if you need to break away. Descending on the dead side gives you good opportunities to spot other traffic already in the pattern as you descend, and crossing the departure end of the runway puts you well above departing traffic. This probably works best in high-wing aircraft.

Finally, I've also heard that military aircraft may use different procedures, at least at military airfields. SSumner mentioned in a comment below that the US Air Force uses either the 45-degree entry recommended by the FAA ("VFR entry") or a straight-in approach ("initial entry").

Answer 3

In the Navy, anytime we make a perpendicular entry to the pattern we turn directly downwind. I'd have to agree with the controller, its a waste of precious time, especially during busy operations, to wait for someone to make a 360 and slam the pattern. I can't see any useful safety benefit either, if you didn't see aircraft X as it was moving horizontally across your windscreen, what makes you think you'll see it any better by executing a 360?

Answer 4

I was instructed at an uncontrolled field in Canada some 15 years ago. For a right-hand circuit as shown, if arriving from what would be the west in your illustration, you cross mid field at pattern altitude and turn right to join the downwind. If arriving from the east, you should join the downwind leg at its upwind end. For a left-hand circuit, everything is reversed. In any case, you are typically making no more than a 90 degree turn to join the downwind and you don't cross it.

At a controlled airport, you will probably be cleared to join whichever leg is most closely aligned to your arrival heading; you might therefore fly straight in to the crosswind, downwind, base, or final leg.

This Wikipedia article includes procedures for a number of jurisdictions including the US and Canada (which is as I described above), and makes the point that things are done differently in different jurisdictions.

Answer 5

Yep, that's exactly what they teach in the UK. Trouble is, all the depictions of this "Standard Overhead Join" always show you coming in from the liveside, descending deadside, and then joining crosswind at circuit height. But what does it look like if you're arriving from the deadside? Easy answer would be to join straight into the crosswind leg at circuit height. An ATC may let you do that. However, at uncontrolled airfields, the expectation is that you spend enough time overhead the a/d in order to determine wind, rwy in use, etc. According to this, you'd have to come in on the upwind side above circuit height, loop around on the liveside above circuit height, cross the rwy again on the downwind side, still above circuit height, then head upwind on the deadside ("deadside descending"), drop to circuit height, and then join the circuit on the crosswind leg. That will give you a total of seven 90 degree turns before you land ...

Answer 6

Check this out from the NZ CAA:

This lesson covers vacating and joining at controlled and uncontrolled aerodromes. Elements may be combined with other training area exercises (refer CFI).

Where no other method is published, the standard overhead join procedure is the preferred method for joining the traffic circuit at an unattended aerodrome. It is used when the pilot-in-command needs to find out the runway in use, familiarise themselves with the aerodrome traffic and conditions, or when required by ATC.

The Standard Overhead Joining poster is a good resource for this briefing.

Objectives

To vacate and join the circuit in accordance with applicable procedures.

To join an uncontrolled circuit in accordance with the standard overhead join procedure.

Considerations Discuss vacating the uncontrolled aerodrome first. As with a clearance, all of these methods are also available at controlled aerodromes.

Uncontrolled Aerodromes

Vacating

Leaving the circuit at an uncontrolled aerodrome is usually done from one of the circuit legs, climbing straight ahead on the runway heading to 1500 feet above aerodrome level, or from crosswind or downwind, or climbing to overhead – remembering that turns are always in the circuit direction.

Standard Overhead Join

Rule 91.223 Operating on and in the vicinity of an aerodrome requires the pilot to "…observe other aerodrome traffic for the purpose of avoiding collision, and, unless otherwise authorised or instructed by ATC, conform with or avoid the aerodrome traffic circuit formed by other aircraft." The standard overhead join procedure is a recommended means of complying with this rule, by being 500 feet above aerodrome traffic and then sequencing appropriately.

At an unattended aerodrome there will be no ATC instructions, and there may be no ATIS to forewarn the pilot of runway in use and wind conditions.

If the aerodrome is listed in AIP Vol 4, circuit direction will be shown on the aerodrome chart. This information and an estimate of the surface wind can provide a clue to the circuit direction.

Even if the runway in use is known, the pilot may elect to carry out the standard procedure if they are unfamiliar with the aerodrome layout and unsure of the location of other traffic.

The term 'overhead' is used because the aeroplane is flown over the aerodrome at a safe altitude above the circuit to look down and determine which runway is in use, or most suitable, and to sight any traffic.

It is important to realise that there may be traffic without a radio, NORDO (non-radio), and your only method of avoiding collision with them is to sight them and work out what they are doing from their position and movements.

Discuss the information found on the aerodrome chart that is applicable to the standard overhead join procedure. This includes; aerodrome elevation, runways available and their suitability, circuit directions, specific aerodrome instructions, the location of windsocks, and how to hold the chart to aid orientation. If the aerodrome is unfamiliar to the student, a study of the aerodrome chart should be carried out before flight.

Discuss the requirement to terminate the flight plan with ATC after landing at uncontrolled aerodromes.

Simulating a standard overhead join by 'walking and talking the pattern' beforehand can be a useful tool to prepare the student for this exercise.

Controlled Aerodromes

Vacating

When vacating a controlled aerodrome, all of the previously mentioned options are available. In addition, a clearance to turn in the opposite direction to the published circuit may be given by ATC, or requested by the pilot. If a non-standard clearance is required, keep a good lookout and request it before takeoff.

Joining

When joining at a controlled aerodrome, the pilot-in-command has the option of requesting a standard overhead join. This is a good idea if the pilot is unfamiliar with the aerodrome layout, the active runway, or the position of the various circuit legs. ATC also has the option of instructing the pilot to carry out a standard overhead join.

However, the most common method of joining at a controlled aerodrome is to be cleared by ATC to join on the downwind, base, or final approach legs. Such a clearance may be for an aerodrome traffic circuit opposite to the published circuit for that runway; for example, "join right base" for a runway with a lefthand circuit.

Another possible clearance is to "cross overhead and join downwind". This is not a standard overhead join.

It is good aviation practice to establish the aircraft on an extension of the circuit leg to be joined, well before reaching the circuit area.

Where ATC is in attendance, but ATIS is not available, common practice is to request joining instructions. ATC will inform the pilot of the conditions and clear the pilot to join the circuit in the most appropriate way.

When ATIS information has been received before reaching the reporting point for circuit joining, the pilot should state or request from ATC the preferred method of joining.

A clearance to join downwind, base, or final does not absolve the pilot from giving way to other aircraft already established in the circuit.

Aerodrome Flight Information Service

Where an aerodrome flight information service (AFIS) is provided, joining and departing procedures specific to that aerodrome will apply. This may include the standard overhead rejoin.

When joining at an aerodrome with AFIS a radio call at 5–10 miles (or a position determined by the airspace) is required to state your position, altitude, intentions and POB. The AFIS will advise the ATIS, QNH and traffic information. The arriving aircraft then advises more specific intentions based on the information received.

Airmanship

Preparing the aeroplane for arrival involves the use of AIP Vol 4, the VNC (Visual Navigation Chart 1:250000 or 1:125000 if applicable) and joining checklists.

Revise the right-of-way rules and emphasise the requirement to make turns in the circuit direction.

If a downwind leg will not be flown, the aeroplane is prepared for landing before circuit entry by using joining and prelanding checks.

There is a tendency for the student to rely on radio calls during the overhead join, and to make too many. It is critical that a good lookout is carried out to identify all aircraft operating in the circuit, including those without radios.

The overhead joining procedure is used to determine the runway in use and the position of traffic in order to sequence accordingly. It does not presume a right of way over existing circuit activity. Orbiting overhead may be necessary until safe sequencing is available.

Aeroplane Management

Before entering the circuit, the aeroplane's speed will need to be reduced to below 120 knots, where applicable, as circuit speeds are normally restricted to this.

The landing light should be on.

Human Factors

As the student is orbiting overhead encourage them to get oriented by using the aerodrome chart and wind socks for indications of runway in use.

The limitations of vision are revised in relation to closure rates and objects that do not produce relative movement.

There is a lot of information to take in while approaching and orbiting overhead. Encourage the student to approach it systematically.

Air Exercise

Vacating

Discuss the way you would normally vacate your home aerodrome circuit, and the way you would vacate the other type of aerodrome.

Uncontrolled Aerodrome Joining

When joining at an unattended aerodrome, a radio call addressed to the circuit traffic is made between 5 and 10 NM from the aerodrome, stating your position, altitude, and intentions. The standard overhead join procedure is carried out in three main phases.

Standard Overhead Join

Approach

Approach the aerodrome to cross overhead at not less than 1500 feet above aerodrome level (refer landing chart) unless otherwise stated on the landing chart; for example, at Palmerston North 1500 feet amsl is used because of airspace above.

When calculating the altitude to join overhead at, round up – assuming there is no overlying airspace restriction. For example, if aerodrome elevation is 150 feet, rejoin altitude would be 1650 or 1700 feet not 1600 feet. The reason for rounding up is to maintain a 500-foot buffer over aircraft in the circuit, which may have rounded up the circuit altitude. At altitudes above 1500 feet it is harder to distinguish the windsocks, and more altitude will need to be lost on the descent. In addition, if all aircraft rejoin at the same altitude it should be easier to see each other.

The aeroplane should be positioned overhead and right of centreline, so that the student can look out of their window, down and across the whole aerodrome, observing traffic, windsocks and ground signals or markings.

Determine Runway in Use

Firstly the student must determine which runway is in use, as this sets which direction to make all turns, and the traffic and non-traffic sides.

Runway in use can be worked out by observing the windsocks, or other traffic already established in the circuit. If the runway in use cannot be determined quickly, make a turn to the left and continue to orbit left, until it is determined. If it is then found that a righthand circuit is in use, make all further turns to the right.

Be aware that many airfields have alternate circuit patterns for helicopter and glider traffic. If they are in use, joining aircraft must sequence into the circuit without causing conflict.

Both the traffic and non-traffic side must be identified to avoid descending onto aircraft already in the circuit. One method of identifying the traffic side is to have the student imagine they are lined up on the chosen runway ready for takeoff. If they were to takeoff which way would they turn at 500 feet – this establishes the traffic side.

Once the runway in use has been established and the circuit direction is confirmed (refer landing chart), a turn is made in the circuit direction to position the aeroplane on the non-traffic side. As aerodromes are potentially areas of high traffic density, use no more than a medium angle of bank. At this point it is good aviation practice to make a radio call advising traffic of the runway you are joining for.

Aircraft already in the circuit have right of way. This means that if aircraft in the circuit are using a runway considered unsuitable for your operation, the responsibility of avoiding conflict is on the joining aircraft, even if the runway in use is out of wind.

Regardless of which way the aeroplane is turning, the turn is continued until the centreline of the runway in use is crossed, and the aeroplane enters the non-traffic side.

Avoid giving too much attention to ground features during these phases, maintaining a lookout for other aircraft is more important as NORDO aircraft will not be heard and must be seen.

Descend to Circuit Height

When established on the non-traffic side descend to circuit altitude. A low rate of descent is preferred because of the potentially high traffic density around an aerodrome. Common practice is to use a cruise or powered descent.

The aeroplane must cross onto the traffic side of the active runway only when at circuit altitude. They should also track over the upwind threshold. Crossing the upwind threshold provides the longest possible downwind leg, while at the same time still providing maximum vertical separation from high-performance aeroplanes taking off.

As the downwind leg will be shorter than normal, the prelanding checks can be completed during the descent on the non-traffic side or on the crosswind leg (refer CFI).

On this crosswind leg, correct for drift, in order to track at right angles to the runway. A good lookout will need to be maintained for aircraft flying on the downwind leg. Do not turn in front of any such aircraft – always position behind.

The downwind radio call is made as soon as the aeroplane is established on the downwind leg, and the circuit is completed in the normal manner.

Controlled Aerodrome Joining

The standard overhead join can be carried out at controlled aerodromes, with a clearance from ATC. More normally you will join via one of the circuit legs, usually downwind or via base leg.

Consult AIP Vol 4 for differences, particularly where there are neighbouring aerodromes.

Airborne Sequence

On the Ground

Make sure the student has all the necessary information to hand, and they have briefed themselves on the landing chart.

The Exercise

Vacate the circuit the way you are either cleared by ATC, or the way you discussed in the briefing.

They will have already seen, in previous lessons, how to vacate the circuit, but you may need to prompt some of the radio calls.

If you will be using your home aerodrome for the standard overhead joining procedure, head away in an unfamiliar direction, to add a little realism.

Begin the exercise between 10 and 5 NM from the aerodrome, over a local feature or VFR reporting point.

Talk through the standard overhead join procedure, and then have the student practise before any solo practise.

From the downwind leg, an approach and landing or go around can be carried out before vacating the circuit for student practice. If this is your home aerodrome, you may want to skip the landing, however, if it is an unfamiliar aerodrome landing practice would be beneficial.

After Flight

There probably won't have been time to cover every method of vacating and joining the circuit, so advise the student that you will take the opportunity in future lessons to practice these different methods.

Figure 1 - The Standard Overhead Join.

Answer 7

First off, there is a reason they are called "uncontrolled" airports. Read the FAR's: the guidance is just that, "guidance", there are very few "rules".... the local pattern police not withstanding.

While most of the above comments are technically correct and do not violate any rules, none of the comments address the jet operator who is faster and uses more real estate in a traffic pattern. Jets are encouraged to use a 1500' pattern while non-jets use a 1000' pattern. The result? At some point, the jet is descending through the 1000' pattern into slower traffic.

See the problem?

Generally jets are equipped with TCAS and can see any aircraft that has an operating transponder. The nightmare for the jet pilot entering an uncontrolled airport's traffic pattern at night and having a NORDO J-3 with a battery powered set of position lights (the J-3 is completely legal). Can you imagine sailing down final at 140 Kts and trying to see the 45 KT J-3's dim, single tail light?

From my perspective, the safest thing a jet can do is enter a long (more than 2 miles) straight-in final, talk on the radio, watch for TCAS targets and be "in the pattern" for the least amount of time possible.

YMMV