Procedures and approaches

Beginner

Aircraft do not fly random lines. They fly on published routes that have names. Before you speak, most of your traffic is on one of these routes.

How to control traffic Step 6 of 8

Four parts in sequence

From en route to the runway: arrival, transition, approach.

SID — the departure route, from the runway to the airway structure.
STAR — the arrival route, from the airway structure to your airport.
Transition — the feeder that connects the end of a STAR to the start of an approach. A transition clearance only adds the feeder to the route. To capture the approach, the aircraft must also get its approach clearance.
Approach — the last path down to the runway. The game has ILS and RNAV approaches, and also the usual civil GLS, GPS, localizer, VOR and NDB families.

In the clearance for each part, you use the name of the part:

Iberia one two three four, cleared ADUXO two delta arrival

On a published DME arc, the aircraft follows the curve onto the next route leg, without a direct-to from you.

An approach leg can end at a specified distance from a DME beacon. The aircraft and route preview use that distance. Not in 0.6.2.552

Distance example from the LEZL ILS Z runway 27 approach. This schematic shows the leg before the arc.

A STAR and an approach on the radar, with waypoints and altitude constraints. — Procedures on the scope, with their published altitude constraints.

Published constraints and the descent along them

With a descend-via clearance, the arrival descends at each published constraint without more instructions.

Procedures have altitude and speed limits at some fixes, for example “at or below 7,000 at this fix”. You do not have to give each step of the descent. You can give the full descent in one clearance:

Iberia one two three four, descend via ADUXO two delta to flight level one zero zero

Then the aircraft obeys each published limit and stops at the level that you gave. climb via does the same for a departure on a SID.

The clearance also operates without a level. descend via ADUXO two delta descends the aircraft to the lowest published altitude of the arrival. climb via climbs a departure to the top altitude of its SID.

Speed limits also follow the route. On an arrival, the last limit that the aircraft flew through stays a maximum until a subsequent limit replaces it. On a SID, a limit is applicable only until its fix. After that fix, the aircraft has no speed limit, but it must stay at 250 kt or less below flight level 100. An arrival that starts on a departure route obeys the speed and altitude limits of that route in the same way, until it passes each fix. Not in 0.6.2.552

After the aircraft flies through a route fix, the guidance continues forward. It does not turn back to that fix.

An altitude clearance without “via” is different. The aircraft keeps the restrictions that it can obey. It cancels only the restrictions that do not agree with the new altitude.

The clearance that controllers frequently do not give

Vectors point the aircraft to the final. Only the clearance lets it intercept.

This is the most frequent problem in the game:

This rule is also applicable to arrivals. An aircraft with a STAR clearance flies the STAR and then stops at the end of it. This also occurs when you gave expect runway two four left. Expect prepares the aircraft, but it does not clear it. The approach clearance is always a different instruction.

You can change the expected runway at all times, also when the aircraft flies the arrival. The aircraft then changes only the part of its route that it did not fly.

Some arrivals have no STAR because the available arrival routes start on the other side of the airport. Their flight plan ends at the first fix of an approach. The aircraft descends to that fix and calls about two minutes before it. It holds there until you give an approach clearance or radar vectors.

Short flights from a nearby airport can also end at one fix that is not on an arrival route, often a VOR. The same occurs when the only arrival routes at the last fix serve the other runway direction. The aircraft treats that fix as its clearance limit and expects the approach to the runway in use. It does not plan the fix below the first altitude of that approach. Give it radar vectors to the final course, then the approach clearance. If you do not, it calls about two minutes before the fix and holds there. Not in 0.6.2.552

A short flight from your airport to a nearby airport can also have one fix, with no SID to it. The aircraft flies the SID of the runway in use to its point nearest that fix, then direct to the fix. If that SID starts with a heading for radar vectors, the aircraft keeps the heading until you give vectors or a direct clearance to the fix. These short flights cruise low, usually between 4,000 and 10,000 ft. Not in 0.6.2.552

To send the aircraft through one feeder fix in the same instruction:

Iberia one two three four, via LESBA, cleared ILS approach runway two four left

Some approaches align with the runway only in the last mile. On the chart, the aircraft flies to the other side of the airport. Then it turns onto the centerline a short distance from the runway. The RNAV X to runway 31 at LaGuardia is a good example.

With a clearance for this type of approach, the aircraft flies one stable descent around the turn to the landing. This is correct, and it is not an overshoot. The check for a stable approach follows the curved path through the turn, so the turn does not cause a go-around.

The side is as important as the angle. From one side, a thirty-degree heading intercepts the final approach course. From the other side, the same heading increases the distance to the course. If you clear an aircraft on a heading that cannot get it to the course, the pilot tells you that the aircraft will not intercept. Then the aircraft cancels the approach and keeps flying your vectors. It does not go around. Prepare a new intercept. Then give a new approach clearance.

Transitions that wait for you

At the end of some transitions, the aircraft waits for your next instruction.

A published heading. The Sabadell 2 Whiskey transition at Barcelona ends on heading 064. The aircraft keeps this heading and waits for a base turn. At this point, an approach clearance does not turn the aircraft. The pilot speaks maintaining heading zero six four, say base. Give the base turn with a heading (turn right heading two one four) or with a direct-to a base fix.
A fix and no heading. The aircraft holds at the last fix. It uses the published hold or a standard right-hand hold. The pilot tells you that the aircraft is in the hold. When you clear the approach, the aircraft flies to the fix again and captures the approach.
The aircraft is on the transition. If you clear the same transition again, the pilot speaks already on Sabadell two whiskey. If the aircraft is on vectors, give the name of the fix where it goes onto the transition: direct BL431, cleared Sabadell two whiskey transition. If you do not give a fix, the pilot speaks say fix to join.

Instrument approach guidance

Letters, for example Y and Z, identify different published procedures for the same runway. Select one procedure in the menu. As an alternative, speak an ILS clearance without the letter, and the game selects an available procedure. The letter does not change the limit of 45 degrees for the intercept angle.

The aircraft captures the localizer like a real autopilot, and there is no limit of 45 degrees. Not in 0.6.2.552 It starts the turn onto the final approach course when the distance to the course is equal to the distance that the turn needs. Each heading that gets the aircraft to the course at less than 90 degrees is applicable. If you give a steep intercept or a late intercept, the aircraft flies through the centerline. Then it turns back and captures the localizer. An early, shallow intercept gives a capture with no overshoot.

You can clear the approach while the pilot gives the readback for your last heading instruction. The aircraft first obeys that heading and turn direction. Then the approach guidance starts. If you save and load the game during the readback, the game keeps the two instructions.

An aircraft can be in a position where it cannot do a protected intercept before the final approach fix. Then the pilot tells you that the aircraft cannot intercept the approach and must have more instructions. The procedure stays available. Move the aircraft to an applicable position and altitude. Then clear it again.

A climb instruction to an aircraft that is established on the approach cancels the approach. The aircraft keeps its present heading and climbs. Clear the approach again when you want it back. A climb instruction before the aircraft is established also cancels the approach. On a heading, the aircraft keeps its heading. On its route, it keeps its route. Not in 0.6.2.552 On a visual approach route, the pilot keeps the sight report. Thus, a new visual approach clearance operates immediately. Not in 0.6.2.552

This is also applicable when the localizer is only armed. The aircraft flies on to the heading that you gave. If you give the approach clearance after the climb, the approach stays: Iberia one two three four, climb five thousand feet, cleared ILS approach runway two seven. A descent that you give before the pilot starts the climb does not bring the approach back. Not in 0.6.2.552

A heading to an aircraft that you cleared on its procedure cancels the approach clearance, the same as a direct-to. The aircraft flies your heading. To keep the clearance, give the heading and the clearance in one call: turn left heading one eight zero, cleared ILS approach runway two seven. Not in 0.6.2.552

If the ILS procedure contains a glide-slope intercept altitude, the aircraft uses that altitude as a descent target. Published altitude restrictions continue to apply. New in 0.6.3.8

Join the localizer below the glide slope. The glide slope is available up to 35 NM from the runway, and the aircraft captures it from below. If the aircraft joins above the glide slope, the pilot speaks established localizer, high on the glideslope and descends to get onto it before 1,000 ft above the airport. If it cannot, the pilot speaks unable to make the glideslope, too high, going around and flies the missed approach.

After the aircraft captures the ILS glide slope, it follows the published descent path. Step-down altitudes for a nonprecision final approach do not stop this descent. Published limits before the final approach still apply. New in 0.6.3.8

The approach name tells you the type of guidance on the final:

Approach	Lateral guidance	Vertical guidance
ILS	Front-course localizer	Published glide slope (`G/S`)
GLS	Published final course	Published glide path (`G/P`)
RNAV, RNP or GPS	Published route and final course	Coded path (`PATH`) or step-downs
LOC	Front-course localizer	Coded path or step-downs
LOC back course	Published back course	Coded path or step-downs, not the front G/S
LDA	Offset localizer	Published G/S, or path or step-downs if there is no G/S
VOR, VOR/DME, VORTAC, NDB or NDB/DME	Published route and final course	Coded path or step-downs

The game does not make a glide path that is not published. An approach without a path obeys each published altitude restriction. It can stop its descent at a step-down fix.

The aircraft keeps this descent after it joins the final course. It levels off where the vertical profile (Shift+V) shows a level. If you clear it for the approach from vectors, it keeps your altitude until it joins the final course. Then it descends through the published altitudes that are still ahead. At its minimum it looks for the runway: it leaves the minimum where a 3° descent reaches the runway, lines up with it and lands. If it gets to the minimum later, it may descend more steeply, at up to 1,000 ft per minute. If that is not enough, or it reaches the missed approach point first, it flies the published missed approach and says “going around, unable to land”. Shift+V shows this last descent.

WPT shows the full identifier of the instrument approach. A * shows that the lateral guidance is armed. Named visual approaches and generic visual approaches show Visual in WPT.

CFL shows G/S, G/P or PATH when that guidance is active. While that guidance is armed, CFL shows the same name with a *. When CFL does not show one of these names, a cleared approach shows APP, without an altitude after it.

At the missed approach point, an aircraft on a stable straight-in approach continues with visual reference to the landing. If the aircraft is not stable or if its guidance stops, it goes around. The game does not make a circling approach.

An RNP AR approach must use the full published procedure. The aircraft does not accept vectors to final. But it accepts a direct-to clearance to a published entry fix.

The next page, Visual approaches, shows how to clear an aircraft for a visual approach.

When an approach cannot continue

The climb starts immediately. A turn before the missed approach point waits until that point.

When the landing of an instrument arrival is not possible, tell it to go around:

Iberia one two three four, go around

The aircraft climbs immediately. If it is before the missed approach point, it stays on the final path until that point. Then it flies the published missed route and the published hold, if there is one. If the go-around starts at or after the missed approach point, the aircraft flies onto the missed route in front of it. It does not turn back.

If you gave a level just before the go-around and the pilot did not start it, the aircraft ignores it. It flies the missed approach altitude. Not in 0.6.2.552

If the missed route ends at a fix and no hold follows it, the aircraft holds at that fix and asks you for further instructions one time. It uses the hold that the chart publishes at that fix. If there is no published hold, it flies a one-minute hold with right turns on the last course.

If the missed route ends at an altitude and not at a fix, the aircraft keeps the last course and altitude. It asks you for further instructions one time.

An instrument approach with vectors keeps the published missed procedure of that approach. This includes the selected Y or Z procedure.

If you want different instructions, add a heading, an altitude, or a heading and an altitude:

Iberia one two three four, go around, fly heading two six five, climb and maintain three thousand

The aircraft also goes around for these causes:

The approach is not stable for a long period.
An aircraft is on the runway.
The aircraft cannot see the modeled visual reference.
The approach guidance does not operate.

On an instrument approach, the pilot checks that the approach is stable from 1,000 ft above the airport, but only after the final approach fix. A low arrival far out is not sent around before it joins the approach. New in 0.6.3.7

The pilot goes around for sinking too fast above 1,000 ft per minute. On a glideslope steeper than 3 degrees, such as the ILS 34L at Rome (3.5 degrees), the limit is the sink rate that the glideslope needs at the ground speed of the aircraft plus 100 ft per minute, if that is higher. A fast or heavy aircraft can stay on that glideslope and land.

Every automatic go-around call, on every approach type, names the reason: going around, too high, too low, too fast, too slow, sinking too fast, off course or off the centerline. Before, it said unstable approach or approach guidance failure.

A pilot can also start a go-around on a stable final. The risk is 0.2% for each approach, approximately one in 500. The pilot speaks “going around, unable to land”. Give the same missed-approach instructions. If you save and load the game again, the game does not calculate the risk again for that approach.

You can cancel a manual go-around with disregard, in the usual time limit for that command. You cannot cancel an automatic go-around. This is also applicable to a go-around that the pilot starts.

Holding

A hold is a published racetrack pattern at a fix. You use it to keep an aircraft in one area when you must have more time. The aircraft calculates the correct entry from the direction that it comes from.

Iberia one two three four, hold over NEPAL

If the fix has a published hold, the aircraft flies it: the published inbound track, turn direction and leg length. Some fixes have more than one hold. The aircraft flies the hold for its altitude that agrees with the track it flies to the fix. If the fix has no published hold, the aircraft flies a standard hold: right turns, inbound on the heading that it has when the hold starts, and one-minute legs (1.5 minutes above 14,000 ft). Not in 0.6.2.552

Some fixes have no hold record, but an arrival, departure or approach chart shows a hold there. At such a fix, the aircraft flies that charted hold. For example, at NIKAL (Seville) it flies the runway 27 missed approach hold: inbound 184, right turns.

The entry is a direct, parallel or teardrop entry, as the published procedures describe. On the outbound leg, the aircraft starts to count the leg time when it is abeam the fix, or when its turn ends if that is later. On the inbound leg, it follows the inbound course to the fix, and turns back onto that course when it is off it. Not in 0.6.2.552

Near the airport, the aircraft holds ready for the approach. At the final approach fix of its approach it flies about 160 kt. Elsewhere within 10 NM and below 5,000 ft it flies about 180 kt. If you clear the approach from the hold, the pilot starts to slow down at once and can be stable in time. New in 0.6.3.7

When a route stops

Some published legs end with an open heading, and not at a fix. The procedure tells the pilot “fly this heading until further instruction”. The route preview shows a break at that point. It does not make a shortcut to the next fix. This break tells you to give the next lateral clearance.

While a heading from you or from the procedure is active, the aircraft continues on that heading. The pilot does not tell you that the aircraft must have vectors, and the aircraft does not go into a hold.

Some departures fly a heading only until they get to a radial: “turn left heading 088; when passing GIX R162, continue as cleared”. The aircraft turns in the direction on the chart and flies to that radial. Then it keeps the heading until you give it vectors. If no controller controls the departure at that time, it flies to its next route fix.

All commands gives all procedure commands and the correct words for each command.